Implementing a MMC/SD/SDIO stack using CAM framework(Part 1)
In this blog post we will have a detailed look at all the files added/changed while implementing the MMC/SD/SDIO stack via CAM framework. We will basically discuss the commit https://github.com/freebsd/freebsd/commit/a87c7a85be3e3727b6b08b19741b4282f942400d which aims at adding MMC/SD/SDIO stack to FreeBSD's already existing CAM framework.
So, lets start one by one with each file:
mmc.h
This file presents the basic structure of the SD-Card/MMC peripheral. This structure is further used in CAM_EDT i.e CAM Existing Device Table which stores the info. of all the present devices in the CAM bus along with the queue of pending CCBs. CAM EDT is the major structure describing the CAM bus.
cam_ccb.h
cam_ccb.h is the main header file consisting of major CCB definitions and structure. Have a look at ccb_mmcio stucture, it is the mmc specific CCB that will be used by MMC CAM transport layer. Then, look at ccb_trans_settings_mmc structure, it contains mmc transfer settings like 4/8 bit data bus support, hi speed transfer mode supported or not.
Look at the complete file , There you will notice a number of enumerations, structures, flags describing the CCB. A large part of the CCB is common to all devices, however some part is device specific. For example in our case, struct ccb_mmcio makes up this device(mmc) speciifc part of CCB. Then there's a declaration and defination of the function cam_fill_mmcio which according to my interpretation initializes the CCB.
cam_periph.c
This function just inserts the device mmc in the list of known peripheral modules. It further allocates memory in CCB and do some basic CCB initialization.
cam_xpt.c
This function lays the basics of CAM transport layer whose main function is to take an I/O request along with device path, make a CCB, convert I/O command to SCSI commands, store back those commands in CCB and finally calls the SIM specific routine handling over the CCB along with SCSI command. Notice that the part where information is parred on to the SIM, there is mutual exclusion by mutex, which prevents multiple threads to access SIM concurrently.
mmc_da.c
Now, this is one of the most important file. It provides all device specific functions that takes a CCB, extracts SCSI command and convert it into hardware specific commands. It provides functions to decode the command into expected SD card/ MMC register contents.
Before moving forward, lets have a look at different registers of sd card/mmc:
There are total 8 sd card registers out of which only 6 are common with mmc. Refer https://www.kingston.com/datasheets/SDCIT-specsheet-64gb_en.pdf and this for detailed overview.
First 6 registers are common with MMC.
OCR register describes operating voltage, card power up state and power supply status bits.
CID Card Identification Register, contains vendor specific information about the sd card/mmc. It contains manufacturer id, product name, product serial number etc.
CSD(Card specific data register) contains all card related technical details like maximum data transfer rate, Data read access time, write speed factor etc. It is configurable.
Moving back towards understanding mmc_da.c, first structure to encounter is sdda_softc it contains various hardware specific parameters like sector count ,media size etc. Then there is get_rca function which retrieves the RCA register content. Notice the path carefully(periph->path->device->mmc_ident_data.card_rca)!
Then there is, mmc_decode_csd_sd function that takes raw csd register data, decode it and fill it in mmc_csd structure which is passed on to this function as it's second argument. Have a look at page 88 of this it explains various csd version register structures. Version 0 corresponds to standard capacity sd cards while version 1 corresponds to high capacity sd cards. Version 2 and 3 are still reserved for upcoming versions. Similarly, we have mmc_decode_cid_mmc function which decodes cid register data and stores it in a structure. Function mmc_format_card_id_string formats the SD-card/MMC id which will be used for its identification.
Then we have, sddaschedule which calls xpt_schedule() if device is already in the queue.
xpt_schedule schedules/prepares the peripheral module to recieve the CAM control block (CCB). It then calls xpt_run_dev_allocq which allocates and constructs the CCB. We will look at it in detail, in a later section.
And now we have our star function, sddastrategy
This function is the first one to be called for handling the I/O request by OS. It makes up the CAM peripheral module layer. So, the first thing it does is, bioq_disksort which places the I/O request in the queue. Maintaining a queue is very necessary as to avoid overloading the SIM with requests. Queue can have only a fixed number of CCBs and each executes in an order. It then calls sddaschedule which in turn calls xpt_schedule.
Then, next function we see is sddainit which does some rudimentary initialization before sddastrategy. Then we have sddadiskgonecb ; After sending the CCB to SIM program execution is returned to the caller of sddastrategy but before that sddacleanup is used to cleanup all redundant data and then sddadiskgonecb is called.
and in the function sddaasync notice the switch case statement that handles all these events:
Notice that in case of hot plug/unplug event there will be an async. interrupt that will be handeled by bove function. Then we have mmc_set_timming() which sets the clock frequency of sd-card/mmc. It also determines whether a device supports high speed mode or not and sets the clock frequency accordingly.
sdda_start_init_task allocates and initializes a new CCB block with the received context (I/O request) this will be called after xpt_schedule.
Then we have sddastart(), which is called after xpt_run_alloq_dev. It is the peripheral module start routine which takes a I/O command and convert it into SCSI command.
Notice the switch case statement that converts a command to a more specific SCSI command. For example, BIO_READ is a command to read data from sd/mmc, it after considering the amount of data to be read is converted into MMC_READ_MULTIPLE_BLOCK or MMC_READ_SINGLE_BLOCK. It further performs other functions like flush, delete etc.
sddadone and sddaerr functions will be called by SIM after it completes it's requested operation. Status is stored and checked to raise an alert if unsuccessful.
Other then this file, there are other files that were also changed. W'll look into then into my next post.
So, lets start one by one with each file:
mmc.h
#ifndef CAM_MMC_H
#define CAM_MMC_H
#include <dev/mmc/mmcreg.h>
/*
* This structure describes an MMC/SD card
*/
struct mmc_params {
u_int8_t model[40]; /* Card model */
/* Card OCR */
uint32_t card_ocr;
/* OCR of the IO portion of the card */
uint32_t io_ocr;
/* Card CID -- raw and parsed */
uint32_t card_cid[4];
struct mmc_cid cid;
/* Card CSD -- raw */
uint32_t card_csd[4];
/* Card RCA */
uint16_t card_rca;
/* What kind of card is it */
uint32_t card_features;
#define CARD_FEATURE_MEMORY 0x1
#define CARD_FEATURE_SDHC 0x1 << 1
#define CARD_FEATURE_SDIO 0x1 << 2
#define CARD_FEATURE_SD20 0x1 << 3
#define CARD_FEATURE_MMC 0x1 << 4
#define CARD_FEATURE_18V 0x1 << 5
uint8_t sdio_func_count;
} __packed;
#endif
This file presents the basic structure of the SD-Card/MMC peripheral. This structure is further used in CAM_EDT i.e CAM Existing Device Table which stores the info. of all the present devices in the CAM bus along with the queue of pending CCBs. CAM EDT is the major structure describing the CAM bus.
cam_ccb.h
--- sys/cam/cam_ccb.h
+++ sys/cam/cam_ccb.h
@@ -41,6 +41,7 @@
#include <cam/cam_debug.h>
#include <cam/scsi/scsi_all.h>
#include <cam/ata/ata_all.h>
+#include <cam/mmc/mmc_all.h>
/* General allocation length definitions for CCB structures */
#define IOCDBLEN CAM_MAX_CDBLEN /* Space for CDB bytes/pointer */
@@ -229,6 +230,8 @@
/* Notify Host Target driver of event */
XPT_NOTIFY_ACKNOWLEDGE = 0x37 | XPT_FC_QUEUED | XPT_FC_USER_CCB,
/* Acknowledgement of event */
+ XPT_MMC_IO = 0x38 | XPT_FC_DEV_QUEUED,
+ /* Execute the requested MMC I/O operation */
/* Vendor Unique codes: 0x80->0x8F */
XPT_VUNIQUE = 0x80
@@ -255,6 +258,7 @@
PROTO_ATAPI, /* AT Attachment Packetized Interface */
PROTO_SATAPM, /* SATA Port Multiplier */
PROTO_SEMB, /* SATA Enclosure Management Bridge */
+ PROTO_MMCSD, /* MMC, SD, SDIO */
} cam_proto;
typedef enum {
@@ -270,6 +274,7 @@
XPORT_SATA, /* Serial AT Attachment */
XPORT_ISCSI, /* iSCSI */
XPORT_SRP, /* SCSI RDMA Protocol */
+ XPORT_MMCSD, /* MMC, SD, SDIO card */
} cam_xport;
#define XPORT_IS_ATA(t) ((t) == XPORT_ATA || (t) == XPORT_SATA)
@@ -482,6 +487,7 @@
cam_proto protocol;
struct scsi_inquiry_data inq_data;
struct ata_params ident_data;
+ struct mmc_params mmc_ident_data;
dev_result_flags flags;
};
@@ -745,6 +751,16 @@
u_int init_id; /* initiator id of who selected */
};
+/*
+ * MMC I/O Request CCB used for the XPT_MMC_IO function code.
+ */
+struct ccb_mmcio {
+ struct ccb_hdr ccb_h;
+ union ccb *next_ccb; /* Ptr for next CCB for action */
+ struct mmc_command cmd;
+ struct mmc_command stop;
+};
+
struct ccb_accept_tio {
struct ccb_hdr ccb_h;
cdb_t cdb_io; /* Union for CDB bytes/pointer */
@@ -946,6 +962,26 @@
#define CTS_SATA_CAPS_D_APST 0x00020000
};
+/*
+ * Basically, what earlier was done with updating IOS
+ * now can be done using SET_TRAN_SETTINGS
+ */
+#include <cam/mmc/mmc_bus.h>
+struct ccb_trans_settings_mmc {
+ struct mmc_ios ios;
+#define MMC_CLK (1 << 1)
+#define MMC_VDD (1 << 2)
+#define MMC_CS (1 << 3)
+#define MMC_BW (1 << 4)
+#define MMC_PM (1 << 5)
+#define MMC_BT (1 << 6)
+#define MMC_BM (1 << 7)
+ uint32_t ios_valid;
+
+/* The folowing is used only for GET_TRAN_SETTINGS */
+ uint32_t host_ocr;
+};
+
/* Get/Set transfer rate/width/disconnection/tag queueing settings */
struct ccb_trans_settings {
struct ccb_hdr ccb_h;
@@ -958,6 +994,7 @@
u_int valid; /* Which fields to honor */
struct ccb_trans_settings_ata ata;
struct ccb_trans_settings_scsi scsi;
+ struct ccb_trans_settings_mmc mmc;
} proto_specific;
union {
u_int valid; /* Which fields to honor */
@@ -1211,6 +1248,7 @@
struct ccb_ataio ataio;
struct ccb_dev_advinfo cdai;
struct ccb_async casync;
+ struct ccb_mmcio mmcio;
};
__BEGIN_DECLS
@@ -1244,6 +1282,13 @@
uint32_t timeout);
static __inline void
+cam_fill_mmcio(struct ccb_mmcio *mmcio, uint32_t retries,
+ void (*cbfcnp)(struct cam_periph *, union ccb *), uint32_t flags,
+ uint32_t mmc_opcode, uint32_t mmc_arg, uint32_t mmc_flags,
+ struct mmc_data *mmc_d,
+ uint32_t timeout);
+
+static __inline void
cam_fill_csio(struct ccb_scsiio *csio, u_int32_t retries,
void (*cbfcnp)(struct cam_periph *, union ccb *),
u_int32_t flags, u_int8_t tag_action,
@@ -1329,6 +1374,34 @@
}
static __inline void
+cam_fill_mmcio(struct ccb_mmcio *mmcio, uint32_t retries,
+ void (*cbfcnp)(struct cam_periph *, union ccb *), uint32_t flags,
+ uint32_t mmc_opcode, uint32_t mmc_arg, uint32_t mmc_flags,
+ struct mmc_data *mmc_d,
+ uint32_t timeout)
+{
+ mmcio->ccb_h.func_code = XPT_MMC_IO;
+ mmcio->ccb_h.flags = flags;
+ mmcio->ccb_h.retry_count = retries;
+ mmcio->ccb_h.cbfcnp = cbfcnp;
+ mmcio->ccb_h.timeout = timeout;
+ mmcio->cmd.opcode = mmc_opcode;
+ mmcio->cmd.arg = mmc_arg;
+ mmcio->cmd.flags = mmc_flags;
+ if (mmc_d != NULL) {
+ mmcio->cmd.data.len = mmc_d->len;
+ mmcio->cmd.data.data = mmc_d->data;
+ mmcio->cmd.data.flags = mmc_d->flags;
+ }
+ else
+ mmcio->cmd.data.len = 0;
+ mmcio->cmd.resp[0] = 0;
+ mmcio->cmd.resp[1] = 0;
+ mmcio->cmd.resp[2] = 0;
+ mmcio->cmd.resp[3] = 0;
+}
+
+static __inline void
cam_set_ccbstatus(union ccb *ccb, cam_status status)
{
ccb->ccb_h.status &= ~CAM_STATUS_MASK;
cam_ccb.h is the main header file consisting of major CCB definitions and structure. Have a look at ccb_mmcio stucture, it is the mmc specific CCB that will be used by MMC CAM transport layer. Then, look at ccb_trans_settings_mmc structure, it contains mmc transfer settings like 4/8 bit data bus support, hi speed transfer mode supported or not.
Look at the complete file , There you will notice a number of enumerations, structures, flags describing the CCB. A large part of the CCB is common to all devices, however some part is device specific. For example in our case, struct ccb_mmcio makes up this device(mmc) speciifc part of CCB. Then there's a declaration and defination of the function cam_fill_mmcio which according to my interpretation initializes the CCB.
cam_periph.c
-- sys/cam/cam_periph.c
+++ sys/cam/cam_periph.c
@@ -777,6 +777,20 @@
dirs[0] = ccb->ccb_h.flags & CAM_DIR_MASK;
numbufs = 1;
break;
+ case XPT_MMC_IO:
+ printf("cam_periph_mapmem: MMCIO flags %02x\n", ccb->ccb_h.flags);
+ if ((ccb->ccb_h.flags & CAM_DIR_MASK) == CAM_DIR_NONE)
+ return(0);
+ if (ccb->mmcio.cmd.data.len == 0) {
+ printf("cam_periph_mapmem: almost failed!...\n");
+ return(0);
+ }
+ printf("cam_periph_mapmem: Setting up memory map...\n");
+ data_ptrs[0] = (unsigned char **)&ccb->mmcio.cmd.data.data;
+ lengths[0] = ccb->mmcio.cmd.data.len;
+ dirs[0] = ccb->ccb_h.flags & CAM_DIR_MASK;
+ numbufs = 1;
+ break;
case XPT_SMP_IO:
data_ptrs[0] = &ccb->smpio.smp_request;
lengths[0] = ccb->smpio.smp_request_len;
This function just inserts the device mmc in the list of known peripheral modules. It further allocates memory in CCB and do some basic CCB initialization.
cam_xpt.c
This function lays the basics of CAM transport layer whose main function is to take an I/O request along with device path, make a CCB, convert I/O command to SCSI commands, store back those commands in CCB and finally calls the SIM specific routine handling over the CCB along with SCSI command. Notice that the part where information is parred on to the SIM, there is mutual exclusion by mutex, which prevents multiple threads to access SIM concurrently.
mmc_da.c
-- /dev/null
+++ sys/cam/mmc/mmc_da.c
@@ -0,0 +1,1140 @@
+/*-
+ * Copyright (c) 2015-2016 Ilya Bakulin <kibab@FreeBSD.org>
+ * All rights reserved.
+ * Lots of code taken from sys/dev/mmc implementation,
+ * thanks to Warner Losh <imp@FreeBSD.org>, Alexander Motin <mav@FreeBSD.org> and other authors.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer,
+ * without modification, immediately at the beginning of the file.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+//#include "opt_sdda.h"
+
+#include <sys/param.h>
+
+#ifdef _KERNEL
+#include <sys/systm.h>
+#include <sys/kernel.h>
+#include <sys/bio.h>
+#include <sys/taskqueue.h>
+#include <sys/lock.h>
+#include <sys/mutex.h>
+#include <sys/conf.h>
+#include <sys/devicestat.h>
+#include <sys/eventhandler.h>
+#include <sys/malloc.h>
+#include <sys/cons.h>
+#include <sys/proc.h>
+#include <sys/reboot.h>
+#include <geom/geom_disk.h>
+#include <machine/_inttypes.h> /* for PRIu64 */
+#endif /* _KERNEL */
+
+#ifndef _KERNEL
+#include <stdio.h>
+#include <string.h>
+#endif /* _KERNEL */
+
+#include <cam/cam.h>
+#include <cam/cam_ccb.h>
+#include <cam/cam_queue.h>
+#include <cam/cam_periph.h>
+#include <cam/cam_sim.h>
+#include <cam/cam_xpt.h>
+#include <cam/cam_xpt_sim.h>
+#include <cam/cam_xpt_periph.h>
+#include <cam/cam_xpt_internal.h>
+#include <cam/cam_debug.h>
+
+
+#include <cam/mmc/mmc_all.h>
+
+#include <machine/md_var.h> /* geometry translation */
+
+#ifdef _KERNEL
+
+typedef enum {
+ SDDA_FLAG_OPEN = 0x0002,
+ SDDA_FLAG_DIRTY = 0x0004
+} sdda_flags;
+
+typedef enum {
+ SDDA_STATE_INIT,
+ SDDA_STATE_INVALID,
+ SDDA_STATE_NORMAL
+} sdda_state;
+
+struct sdda_softc {
+ struct bio_queue_head bio_queue;
+ int outstanding_cmds; /* Number of active commands */
+ int refcount; /* Active xpt_action() calls */
+ sdda_state state;
+ sdda_flags flags;
+// sdda_quirks quirks;
+ struct disk *disk;
+ uint32_t raw_csd[4];
+ struct mmc_csd csd;
+ struct mmc_cid cid;
+ /* Calculated from CSD */
+ uint64_t sector_count;
+ uint64_t mediasize;
+
+ /* Calculated from CID */
+ char card_id_string[64];/* Formatted CID info (serial, MFG, etc) */
+ char card_sn_string[16];/* Formatted serial # for disk->d_ident */
+};
+
+#define ccb_bp ppriv_ptr1
+
+static disk_strategy_t sddastrategy;
+static periph_init_t sddainit;
+static void sddaasync(void *callback_arg, u_int32_t code,
+ struct cam_path *path, void *arg);
+static periph_ctor_t sddaregister;
+static periph_dtor_t sddacleanup;
+static periph_start_t sddastart;
+static periph_oninv_t sddaoninvalidate;
+static void sddadone(struct cam_periph *periph,
+ union ccb *done_ccb);
+static int sddaerror(union ccb *ccb, u_int32_t cam_flags,
+ u_int32_t sense_flags);
+
+static cam_status sdda_hook_into_geom(struct cam_periph *periph);
+static void sdda_start_init(struct cam_periph *periph, union ccb *start_ccb);
+static void sdda_done_init(struct cam_periph *periph, union ccb *done_ccb);
+
+static struct periph_driver sddadriver =
+{
+ sddainit, "sdda",
+ TAILQ_HEAD_INITIALIZER(sddadriver.units), /* generation */ 0
+};
+
+PERIPHDRIVER_DECLARE(sdda, sddadriver);
+
+static MALLOC_DEFINE(M_SDDA, "sd_da", "sd_da buffers");
+
+static const int exp[8] = {
+ 1, 10, 100, 1000, 10000, 100000, 1000000, 10000000
+};
+
+static const int mant[16] = {
+ 0, 10, 12, 13, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 70, 80
+};
+
+static const int cur_min[8] = {
+ 500, 1000, 5000, 10000, 25000, 35000, 60000, 100000
+};
+
+static const int cur_max[8] = {
+ 1000, 5000, 10000, 25000, 35000, 45000, 800000, 200000
+};
+
+static uint32_t
+mmc_get_bits(uint32_t *bits, int bit_len, int start, int size)
+{
+ const int i = (bit_len / 32) - (start / 32) - 1;
+ const int shift = start & 31;
+ uint32_t retval = bits[i] >> shift;
+ if (size + shift > 32)
+ retval |= bits[i - 1] << (32 - shift);
+ return (retval & ((1llu << size) - 1));
+}
+
+
+static void
+mmc_decode_csd_sd(uint32_t *raw_csd, struct mmc_csd *csd)
+{
+ int v;
+ int m;
+ int e;
+
+ memset(csd, 0, sizeof(*csd));
+ csd->csd_structure = v = mmc_get_bits(raw_csd, 128, 126, 2);
+ if (v == 0) {
+ m = mmc_get_bits(raw_csd, 128, 115, 4);
+ e = mmc_get_bits(raw_csd, 128, 112, 3);
+ csd->tacc = (exp[e] * mant[m] + 9) / 10;
+ csd->nsac = mmc_get_bits(raw_csd, 128, 104, 8) * 100;
+ m = mmc_get_bits(raw_csd, 128, 99, 4);
+ e = mmc_get_bits(raw_csd, 128, 96, 3);
+ csd->tran_speed = exp[e] * 10000 * mant[m];
+ csd->ccc = mmc_get_bits(raw_csd, 128, 84, 12);
+ csd->read_bl_len = 1 << mmc_get_bits(raw_csd, 128, 80, 4);
+ csd->read_bl_partial = mmc_get_bits(raw_csd, 128, 79, 1);
+ csd->write_blk_misalign = mmc_get_bits(raw_csd, 128, 78, 1);
+ csd->read_blk_misalign = mmc_get_bits(raw_csd, 128, 77, 1);
+ csd->dsr_imp = mmc_get_bits(raw_csd, 128, 76, 1);
+ csd->vdd_r_curr_min = cur_min[mmc_get_bits(raw_csd, 128, 59, 3)];
+ csd->vdd_r_curr_max = cur_max[mmc_get_bits(raw_csd, 128, 56, 3)];
+ csd->vdd_w_curr_min = cur_min[mmc_get_bits(raw_csd, 128, 53, 3)];
+ csd->vdd_w_curr_max = cur_max[mmc_get_bits(raw_csd, 128, 50, 3)];
+ m = mmc_get_bits(raw_csd, 128, 62, 12);
+ e = mmc_get_bits(raw_csd, 128, 47, 3);
+ csd->capacity = ((1 + m) << (e + 2)) * csd->read_bl_len;
+ csd->erase_blk_en = mmc_get_bits(raw_csd, 128, 46, 1);
+ csd->erase_sector = mmc_get_bits(raw_csd, 128, 39, 7) + 1;
+ csd->wp_grp_size = mmc_get_bits(raw_csd, 128, 32, 7);
+ csd->wp_grp_enable = mmc_get_bits(raw_csd, 128, 31, 1);
+ csd->r2w_factor = 1 << mmc_get_bits(raw_csd, 128, 26, 3);
+ csd->write_bl_len = 1 << mmc_get_bits(raw_csd, 128, 22, 4);
+ csd->write_bl_partial = mmc_get_bits(raw_csd, 128, 21, 1);
+ } else if (v == 1) {
+ m = mmc_get_bits(raw_csd, 128, 115, 4);
+ e = mmc_get_bits(raw_csd, 128, 112, 3);
+ csd->tacc = (exp[e] * mant[m] + 9) / 10;
+ csd->nsac = mmc_get_bits(raw_csd, 128, 104, 8) * 100;
+ m = mmc_get_bits(raw_csd, 128, 99, 4);
+ e = mmc_get_bits(raw_csd, 128, 96, 3);
+ csd->tran_speed = exp[e] * 10000 * mant[m];
+ csd->ccc = mmc_get_bits(raw_csd, 128, 84, 12);
+ csd->read_bl_len = 1 << mmc_get_bits(raw_csd, 128, 80, 4);
+ csd->read_bl_partial = mmc_get_bits(raw_csd, 128, 79, 1);
+ csd->write_blk_misalign = mmc_get_bits(raw_csd, 128, 78, 1);
+ csd->read_blk_misalign = mmc_get_bits(raw_csd, 128, 77, 1);
+ csd->dsr_imp = mmc_get_bits(raw_csd, 128, 76, 1);
+ csd->capacity = ((uint64_t)mmc_get_bits(raw_csd, 128, 48, 22) + 1) *
+ 512 * 1024;
+ csd->erase_blk_en = mmc_get_bits(raw_csd, 128, 46, 1);
+ csd->erase_sector = mmc_get_bits(raw_csd, 128, 39, 7) + 1;
+ csd->wp_grp_size = mmc_get_bits(raw_csd, 128, 32, 7);
+ csd->wp_grp_enable = mmc_get_bits(raw_csd, 128, 31, 1);
+ csd->r2w_factor = 1 << mmc_get_bits(raw_csd, 128, 26, 3);
+ csd->write_bl_len = 1 << mmc_get_bits(raw_csd, 128, 22, 4);
+ csd->write_bl_partial = mmc_get_bits(raw_csd, 128, 21, 1);
+ } else
+ panic("unknown SD CSD version");
+}
+
+static void
+mmc_decode_csd_mmc(uint32_t *raw_csd, struct mmc_csd *csd)
+{
+ int m;
+ int e;
+
+ memset(csd, 0, sizeof(*csd));
+ csd->csd_structure = mmc_get_bits(raw_csd, 128, 126, 2);
+ csd->spec_vers = mmc_get_bits(raw_csd, 128, 122, 4);
+ m = mmc_get_bits(raw_csd, 128, 115, 4);
+ e = mmc_get_bits(raw_csd, 128, 112, 3);
+ csd->tacc = exp[e] * mant[m] + 9 / 10;
+ csd->nsac = mmc_get_bits(raw_csd, 128, 104, 8) * 100;
+ m = mmc_get_bits(raw_csd, 128, 99, 4);
+ e = mmc_get_bits(raw_csd, 128, 96, 3);
+ csd->tran_speed = exp[e] * 10000 * mant[m];
+ csd->ccc = mmc_get_bits(raw_csd, 128, 84, 12);
+ csd->read_bl_len = 1 << mmc_get_bits(raw_csd, 128, 80, 4);
+ csd->read_bl_partial = mmc_get_bits(raw_csd, 128, 79, 1);
+ csd->write_blk_misalign = mmc_get_bits(raw_csd, 128, 78, 1);
+ csd->read_blk_misalign = mmc_get_bits(raw_csd, 128, 77, 1);
+ csd->dsr_imp = mmc_get_bits(raw_csd, 128, 76, 1);
+ csd->vdd_r_curr_min = cur_min[mmc_get_bits(raw_csd, 128, 59, 3)];
+ csd->vdd_r_curr_max = cur_max[mmc_get_bits(raw_csd, 128, 56, 3)];
+ csd->vdd_w_curr_min = cur_min[mmc_get_bits(raw_csd, 128, 53, 3)];
+ csd->vdd_w_curr_max = cur_max[mmc_get_bits(raw_csd, 128, 50, 3)];
+ m = mmc_get_bits(raw_csd, 128, 62, 12);
+ e = mmc_get_bits(raw_csd, 128, 47, 3);
+ csd->capacity = ((1 + m) << (e + 2)) * csd->read_bl_len;
+ csd->erase_blk_en = 0;
+ csd->erase_sector = (mmc_get_bits(raw_csd, 128, 42, 5) + 1) *
+ (mmc_get_bits(raw_csd, 128, 37, 5) + 1);
+ csd->wp_grp_size = mmc_get_bits(raw_csd, 128, 32, 5);
+ csd->wp_grp_enable = mmc_get_bits(raw_csd, 128, 31, 1);
+ csd->r2w_factor = 1 << mmc_get_bits(raw_csd, 128, 26, 3);
+ csd->write_bl_len = 1 << mmc_get_bits(raw_csd, 128, 22, 4);
+ csd->write_bl_partial = mmc_get_bits(raw_csd, 128, 21, 1);
+}
+
+static void
+mmc_decode_cid_sd(uint32_t *raw_cid, struct mmc_cid *cid)
+{
+ int i;
+
+ /* There's no version info, so we take it on faith */
+ memset(cid, 0, sizeof(*cid));
+ cid->mid = mmc_get_bits(raw_cid, 128, 120, 8);
+ cid->oid = mmc_get_bits(raw_cid, 128, 104, 16);
+ for (i = 0; i < 5; i++)
+ cid->pnm[i] = mmc_get_bits(raw_cid, 128, 96 - i * 8, 8);
+ cid->pnm[5] = 0;
+ cid->prv = mmc_get_bits(raw_cid, 128, 56, 8);
+ cid->psn = mmc_get_bits(raw_cid, 128, 24, 32);
+ cid->mdt_year = mmc_get_bits(raw_cid, 128, 12, 8) + 2000;
+ cid->mdt_month = mmc_get_bits(raw_cid, 128, 8, 4);
+}
+
+static void
+mmc_decode_cid_mmc(uint32_t *raw_cid, struct mmc_cid *cid)
+{
+ int i;
+
+ /* There's no version info, so we take it on faith */
+ memset(cid, 0, sizeof(*cid));
+ cid->mid = mmc_get_bits(raw_cid, 128, 120, 8);
+ cid->oid = mmc_get_bits(raw_cid, 128, 104, 8);
+ for (i = 0; i < 6; i++)
+ cid->pnm[i] = mmc_get_bits(raw_cid, 128, 96 - i * 8, 8);
+ cid->pnm[6] = 0;
+ cid->prv = mmc_get_bits(raw_cid, 128, 48, 8);
+ cid->psn = mmc_get_bits(raw_cid, 128, 16, 32);
+ cid->mdt_month = mmc_get_bits(raw_cid, 128, 12, 4);
+ cid->mdt_year = mmc_get_bits(raw_cid, 128, 8, 4) + 1997;
+}
+
+static void
+mmc_format_card_id_string(struct sdda_softc *sc, struct mmc_params *mmcp)
+{
+ char oidstr[8];
+ uint8_t c1;
+ uint8_t c2;
+
+ /*
+ * Format a card ID string for use by the mmcsd driver, it's what
+ * appears between the <> in the following:
+ * mmcsd0: 968MB <SD SD01G 8.0 SN 2686905 Mfg 08/2008 by 3 TN> at mmc0
+ * 22.5MHz/4bit/128-block
+ *
+ * Also format just the card serial number, which the mmcsd driver will
+ * use as the disk->d_ident string.
+ *
+ * The card_id_string in mmc_ivars is currently allocated as 64 bytes,
+ * and our max formatted length is currently 55 bytes if every field
+ * contains the largest value.
+ *
+ * Sometimes the oid is two printable ascii chars; when it's not,
+ * format it as 0xnnnn instead.
+ */
+ c1 = (sc->cid.oid >> 8) & 0x0ff;
+ c2 = sc->cid.oid & 0x0ff;
+ if (c1 > 0x1f && c1 < 0x7f && c2 > 0x1f && c2 < 0x7f)
+ snprintf(oidstr, sizeof(oidstr), "%c%c", c1, c2);
+ else
+ snprintf(oidstr, sizeof(oidstr), "0x%04x", sc->cid.oid);
+ snprintf(sc->card_sn_string, sizeof(sc->card_sn_string),
+ "%08X", sc->cid.psn);
+ snprintf(sc->card_id_string, sizeof(sc->card_id_string),
+ "%s%s %s %d.%d SN %08X MFG %02d/%04d by %d %s",
+ mmcp->card_features & CARD_FEATURE_MMC ? "MMC" : "SD",
+ mmcp->card_features & CARD_FEATURE_SDHC ? "HC" : "",
+ sc->cid.pnm, sc->cid.prv >> 4, sc->cid.prv & 0x0f,
+ sc->cid.psn, sc->cid.mdt_month, sc->cid.mdt_year,
+ sc->cid.mid, oidstr);
+}
+
+static int
+sddaopen(struct disk *dp)
+{
+ struct cam_periph *periph;
+ struct sdda_softc *softc;
+ int error;
+
+ periph = (struct cam_periph *)dp->d_drv1;
+ if (cam_periph_acquire(periph) != CAM_REQ_CMP) {
+ return(ENXIO);
+ }
+
+ cam_periph_lock(periph);
+ if ((error = cam_periph_hold(periph, PRIBIO|PCATCH)) != 0) {
+ cam_periph_unlock(periph);
+ cam_periph_release(periph);
+ return (error);
+ }
+
+ CAM_DEBUG(periph->path, CAM_DEBUG_TRACE | CAM_DEBUG_PERIPH,
+ ("sddaopen\n"));
+
+ softc = (struct sdda_softc *)periph->softc;
+ softc->flags |= SDDA_FLAG_OPEN;
+
+ cam_periph_unhold(periph);
+ cam_periph_unlock(periph);
+ return (0);
+}
+
+static int
+sddaclose(struct disk *dp)
+{
+ struct cam_periph *periph;
+ struct sdda_softc *softc;
+// union ccb *ccb;
+// int error;
+
+ periph = (struct cam_periph *)dp->d_drv1;
+ softc = (struct sdda_softc *)periph->softc;
+ softc->flags &= ~SDDA_FLAG_OPEN;
+
+ cam_periph_lock(periph);
+
+ CAM_DEBUG(periph->path, CAM_DEBUG_TRACE | CAM_DEBUG_PERIPH,
+ ("sddaclose\n"));
+
+ while (softc->refcount != 0)
+ cam_periph_sleep(periph, &softc->refcount, PRIBIO, "sddaclose", 1);
+ cam_periph_unlock(periph);
+ cam_periph_release(periph);
+ return (0);
+}
+
+static void
+sddaschedule(struct cam_periph *periph)
+{
+ struct sdda_softc *softc = (struct sdda_softc *)periph->softc;
+
+ /* Check if we have more work to do. */
+ if (bioq_first(&softc->bio_queue)) {
+ xpt_schedule(periph, CAM_PRIORITY_NORMAL);
+ }
+}
+
+/*
+ * Actually translate the requested transfer into one the physical driver
+ * can understand. The transfer is described by a buf and will include
+ * only one physical transfer.
+ */
+static void
+sddastrategy(struct bio *bp)
+{
+ struct cam_periph *periph;
+ struct sdda_softc *softc;
+
+ periph = (struct cam_periph *)bp->bio_disk->d_drv1;
+ softc = (struct sdda_softc *)periph->softc;
+
+ cam_periph_lock(periph);
+
+ CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, ("sddastrategy(%p)\n", bp));
+
+ /*
+ * If the device has been made invalid, error out
+ */
+ if ((periph->flags & CAM_PERIPH_INVALID) != 0) {
+ cam_periph_unlock(periph);
+ biofinish(bp, NULL, ENXIO);
+ return;
+ }
+
+ /*
+ * Place it in the queue of disk activities for this disk
+ */
+ bioq_disksort(&softc->bio_queue, bp);
+
+ /*
+ * Schedule ourselves for performing the work.
+ */
+ sddaschedule(periph);
+ cam_periph_unlock(periph);
+
+ return;
+}
+
+static void
+sddainit(void)
+{
+ cam_status status;
+
+ /*
+ * Install a global async callback. This callback will
+ * receive async callbacks like "new device found".
+ */
+ status = xpt_register_async(AC_FOUND_DEVICE, sddaasync, NULL, NULL);
+
+ if (status != CAM_REQ_CMP) {
+ printf("sdda: Failed to attach master async callback "
+ "due to status 0x%x!\n", status);
+ }
+}
+
+/*
+ * Callback from GEOM, called when it has finished cleaning up its
+ * resources.
+ */
+static void
+sddadiskgonecb(struct disk *dp)
+{
+ struct cam_periph *periph;
+
+ periph = (struct cam_periph *)dp->d_drv1;
+ CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, ("sddadiskgonecb\n"));
+
+ cam_periph_release(periph);
+}
+
+static void
+sddaoninvalidate(struct cam_periph *periph)
+{
+ struct sdda_softc *softc;
+
+ softc = (struct sdda_softc *)periph->softc;
+
+ CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, ("sddaoninvalidate\n"));
+
+ /*
+ * De-register any async callbacks.
+ */
+ xpt_register_async(0, sddaasync, periph, periph->path);
+
+ /*
+ * Return all queued I/O with ENXIO.
+ * XXX Handle any transactions queued to the card
+ * with XPT_ABORT_CCB.
+ */
+ CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, ("bioq_flush start\n"));
+ bioq_flush(&softc->bio_queue, NULL, ENXIO);
+ CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, ("bioq_flush end\n"));
+
+ disk_gone(softc->disk);
+}
+
+static void
+sddacleanup(struct cam_periph *periph)
+{
+ struct sdda_softc *softc;
+
+ CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, ("sddacleanup\n"));
+ softc = (struct sdda_softc *)periph->softc;
+
+ cam_periph_unlock(periph);
+
+ disk_destroy(softc->disk);
+ free(softc, M_DEVBUF);
+ cam_periph_lock(periph);
+}
+
+static void
+sddaasync(void *callback_arg, u_int32_t code,
+ struct cam_path *path, void *arg)
+{
+ struct ccb_getdev cgd;
+ struct cam_periph *periph;
+ struct sdda_softc *softc;
+
+ periph = (struct cam_periph *)callback_arg;
+ CAM_DEBUG(path, CAM_DEBUG_TRACE, ("sddaasync(code=%d)\n", code));
+ switch (code) {
+ case AC_FOUND_DEVICE:
+ {
+ CAM_DEBUG(path, CAM_DEBUG_TRACE, ("=> AC_FOUND_DEVICE\n"));
+ struct ccb_getdev *cgd;
+ cam_status status;
+
+ cgd = (struct ccb_getdev *)arg;
+ if (cgd == NULL)
+ break;
+
+ if (cgd->protocol != PROTO_MMCSD)
+ break;
+
+ if (!(path->device->mmc_ident_data.card_features & CARD_FEATURE_MEMORY)) {
+ CAM_DEBUG(path, CAM_DEBUG_TRACE, ("No memory on the card!\n"));
+ break;
+ }
+
+ /*
+ * Allocate a peripheral instance for
+ * this device and start the probe
+ * process.
+ */
+ status = cam_periph_alloc(sddaregister, sddaoninvalidate,
+ sddacleanup, sddastart,
+ "sdda", CAM_PERIPH_BIO,
+ path, sddaasync,
+ AC_FOUND_DEVICE, cgd);
+
+ if (status != CAM_REQ_CMP
+ && status != CAM_REQ_INPROG)
+ printf("sddaasync: Unable to attach to new device "
+ "due to status 0x%x\n", status);
+ break;
+ }
+ case AC_GETDEV_CHANGED:
+ {
+ CAM_DEBUG(path, CAM_DEBUG_TRACE, ("=> AC_GETDEV_CHANGED\n"));
+ softc = (struct sdda_softc *)periph->softc;
+ xpt_setup_ccb(&cgd.ccb_h, periph->path, CAM_PRIORITY_NORMAL);
+ cgd.ccb_h.func_code = XPT_GDEV_TYPE;
+ xpt_action((union ccb *)&cgd);
+
+ /*
+ if ((cgd.ident_data.capabilities1 & ATA_SUPPORT_DMA) &&
+ (cgd.inq_flags & SID_DMA))
+ softc->flags |= SDDA_FLAG_CAN_DMA;
+ else
+ softc->flags &= ~SDDA_FLAG_CAN_DMA;
+ if (cgd.ident_data.support.command2 & ATA_SUPPORT_ADDRESS48) {
+ softc->flags |= SDDA_FLAG_CAN_48BIT;
+ if (cgd.inq_flags & SID_DMA48)
+ softc->flags |= SDDA_FLAG_CAN_DMA48;
+ else
+ softc->flags &= ~SDDA_FLAG_CAN_DMA48;
+ } else
+ softc->flags &= ~(SDDA_FLAG_CAN_48BIT |
+ SDDA_FLAG_CAN_DMA48);
+ if ((cgd.ident_data.satacapabilities & ATA_SUPPORT_NCQ) &&
+ (cgd.inq_flags & SID_DMA) && (cgd.inq_flags & SID_CmdQue))
+ softc->flags |= SDDA_FLAG_CAN_NCQ;
+ else
+ softc->flags &= ~SDDA_FLAG_CAN_NCQ;
+ if ((cgd.ident_data.support_dsm & ATA_SUPPORT_DSM_TRIM) &&
+ (cgd.inq_flags & SID_DMA))
+ softc->flags |= SDDA_FLAG_CAN_TRIM;
+ else
+ softc->flags &= ~SDDA_FLAG_CAN_TRIM;
+ */
+ cam_periph_async(periph, code, path, arg);
+ break;
+ }
+ case AC_ADVINFO_CHANGED:
+ {
+ uintptr_t buftype;
+ CAM_DEBUG(path, CAM_DEBUG_TRACE, ("=> AC_ADVINFO_CHANGED\n"));
+ buftype = (uintptr_t)arg;
+ if (buftype == CDAI_TYPE_PHYS_PATH) {
+ struct sdda_softc *softc;
+
+ softc = periph->softc;
+ disk_attr_changed(softc->disk, "GEOM::physpath",
+ M_NOWAIT);
+ }
+ break;
+ }
+ case AC_SENT_BDR:
+ case AC_BUS_RESET:
+ {
+ CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, ("AC_BUS_RESET"));
+/* softc = (struct sdda_softc *)periph->softc;
+ cam_periph_async(periph, code, path, arg);
+ if (softc->state != SDDA_STATE_NORMAL)
+ break;
+ xpt_setup_ccb(&cgd.ccb_h, periph->path, CAM_PRIORITY_NORMAL);
+ cgd.ccb_h.func_code = XPT_GDEV_TYPE;
+ xpt_action((union ccb *)&cgd);
+ if (SDDA_RA >= 0 &&
+ cgd.ident_data.support.command1 & ATA_SUPPORT_LOOKAHEAD)
+ softc->state = SDDA_STATE_RAHEAD;
+ else if (SDDA_WC >= 0 &&
+ cgd.ident_data.support.command1 & ATA_SUPPORT_WRITECACHE)
+ softc->state = SDDA_STATE_WCACHE;
+ else
+ break;
+ if (cam_periph_acquire(periph) != CAM_REQ_CMP)
+ softc->state = SDDA_STATE_NORMAL;
+ else
+ xpt_schedule(periph, CAM_PRIORITY_DEV);
+*/
+ }
+ default:
+ CAM_DEBUG(path, CAM_DEBUG_TRACE, ("=> default?!\n"));
+ cam_periph_async(periph, code, path, arg);
+ break;
+ }
+}
+
+
+static int
+sddagetattr(struct bio *bp)
+{
+ int ret;
+ struct cam_periph *periph;
+
+ periph = (struct cam_periph *)bp->bio_disk->d_drv1;
+ cam_periph_lock(periph);
+ ret = xpt_getattr(bp->bio_data, bp->bio_length, bp->bio_attribute,
+ periph->path);
+ cam_periph_unlock(periph);
+ if (ret == 0)
+ bp->bio_completed = bp->bio_length;
+ return ret;
+}
+
+static cam_status
+sddaregister(struct cam_periph *periph, void *arg)
+{
+ struct sdda_softc *softc;
+// struct ccb_pathinq cpi;
+ struct ccb_getdev *cgd;
+// char announce_buf[80], buf1[32];
+// caddr_t match;
+ union ccb *request_ccb; /* CCB representing the probe request */
+
+ CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, ("sddaregister\n"));
+ cgd = (struct ccb_getdev *)arg;
+ if (cgd == NULL) {
+ printf("sddaregister: no getdev CCB, can't register device\n");
+ return(CAM_REQ_CMP_ERR);
+ }
+
+ softc = (struct sdda_softc *)malloc(sizeof(*softc), M_DEVBUF,
+ M_NOWAIT|M_ZERO);
+
+ if (softc == NULL) {
+ printf("sddaregister: Unable to probe new device. "
+ "Unable to allocate softc\n");
+ return(CAM_REQ_CMP_ERR);
+ }
+
+ bioq_init(&softc->bio_queue);
+ softc->state = SDDA_STATE_INIT;
+
+/*
+ if ((cgd->ident_data.capabilities1 & ATA_SUPPORT_DMA) &&
+ (cgd->inq_flags & SID_DMA))
+ softc->flags |= SDDA_FLAG_CAN_DMA;
+ if (cgd->ident_data.support.command2 & ATA_SUPPORT_ADDRESS48) {
+ softc->flags |= SDDA_FLAG_CAN_48BIT;
+ if (cgd->inq_flags & SID_DMA48)
+ softc->flags |= SDDA_FLAG_CAN_DMA48;
+ }
+ if (cgd->ident_data.support.command2 & ATA_SUPPORT_FLUSHCACHE)
+ softc->flags |= SDDA_FLAG_CAN_FLUSHCACHE;
+ if (cgd->ident_data.support.command1 & ATA_SUPPORT_POWERMGT)
+ softc->flags |= SDDA_FLAG_CAN_POWERMGT;
+ if ((cgd->ident_data.satacapabilities & ATA_SUPPORT_NCQ) &&
+ (cgd->inq_flags & SID_DMA) && (cgd->inq_flags & SID_CmdQue))
+ softc->flags |= SDDA_FLAG_CAN_NCQ;
+ if (cgd->ident_data.support.command2 & ATA_SUPPORT_CFA)
+ softc->flags |= SDDA_FLAG_CAN_CFA;
+*/
+ periph->softc = softc;
+
+ request_ccb = (union ccb*) arg;
+ if (cam_periph_acquire(periph) != CAM_REQ_CMP) {
+ xpt_print(periph->path, "%s: lost periph during "
+ "registration!\n", __func__);
+ cam_periph_lock(periph);
+ return (CAM_REQ_CMP_ERR);
+ }
+ sdda_start_init(periph, request_ccb);
+ xpt_schedule(periph, CAM_PRIORITY_XPT);
+ return (CAM_REQ_CMP);
+
+ /* NOTREACHED */
+}
+
+static cam_status
+sdda_hook_into_geom(struct cam_periph *periph)
+{
+ struct sdda_softc *softc;
+ struct ccb_pathinq cpi;
+ struct ccb_getdev cgd;
+ u_int maxio;
+
+ softc = (struct sdda_softc*) periph->softc;
+
+ bzero(&cpi, sizeof(cpi));
+ xpt_setup_ccb(&cpi.ccb_h, periph->path, CAM_PRIORITY_NONE);
+ cpi.ccb_h.func_code = XPT_PATH_INQ;
+ xpt_action((union ccb *)&cpi);
+
+ bzero(&cgd, sizeof(cgd));
+ xpt_setup_ccb(&cgd.ccb_h, periph->path, CAM_PRIORITY_NONE);
+ cpi.ccb_h.func_code = XPT_GDEV_TYPE;
+ xpt_action((union ccb *)&cgd);
+
+ /*
+ * Register this media as a disk
+ */
+ (void)cam_periph_hold(periph, PRIBIO);
+ cam_periph_unlock(periph);
+
+ softc->disk = disk_alloc();
+ softc->disk->d_rotation_rate = 0;
+ softc->disk->d_devstat = devstat_new_entry(periph->periph_name,
+ periph->unit_number, 512,
+ DEVSTAT_ALL_SUPPORTED,
+ DEVSTAT_TYPE_DIRECT |
+ XPORT_DEVSTAT_TYPE(cpi.transport),
+ DEVSTAT_PRIORITY_DISK);
+ softc->disk->d_open = sddaopen;
+ softc->disk->d_close = sddaclose;
+ softc->disk->d_strategy = sddastrategy;
+ softc->disk->d_getattr = sddagetattr;
+// softc->disk->d_dump = sddadump;
+ softc->disk->d_gone = sddadiskgonecb;
+ softc->disk->d_name = "sdda";
+ softc->disk->d_drv1 = periph;
+ maxio = cpi.maxio; /* Honor max I/O size of SIM */
+ if (maxio == 0)
+ maxio = DFLTPHYS; /* traditional default */
+ else if (maxio > MAXPHYS)
+ maxio = MAXPHYS; /* for safety */
+ softc->disk->d_maxsize = maxio;
+ softc->disk->d_unit = periph->unit_number;
+ softc->disk->d_flags = DISKFLAG_CANDELETE;
+ strlcpy(softc->disk->d_descr, softc->card_id_string,
+ MIN(sizeof(softc->disk->d_descr), sizeof(softc->card_id_string)));
+ strlcpy(softc->disk->d_ident, softc->card_sn_string,
+ MIN(sizeof(softc->disk->d_ident), sizeof(softc->card_sn_string)));
+ softc->disk->d_hba_vendor = cpi.hba_vendor;
+ softc->disk->d_hba_device = cpi.hba_device;
+ softc->disk->d_hba_subvendor = cpi.hba_subvendor;
+ softc->disk->d_hba_subdevice = cpi.hba_subdevice;
+
+ softc->disk->d_sectorsize = 512;
+ softc->disk->d_mediasize = softc->mediasize;
+ softc->disk->d_stripesize = 0;
+ softc->disk->d_fwsectors = 0;
+ softc->disk->d_fwheads = 0;
+
+ /*
+ * Acquire a reference to the periph before we register with GEOM.
+ * We'll release this reference once GEOM calls us back (via
+ * sddadiskgonecb()) telling us that our provider has been freed.
+ */
+ if (cam_periph_acquire(periph) != CAM_REQ_CMP) {
+ xpt_print(periph->path, "%s: lost periph during "
+ "registration!\n", __func__);
+ cam_periph_lock(periph);
+ return (CAM_REQ_CMP_ERR);
+ }
+ disk_create(softc->disk, DISK_VERSION);
+ cam_periph_lock(periph);
+ cam_periph_unhold(periph);
+
+ xpt_announce_periph(periph, softc->card_id_string);
+
+ if (cam_periph_acquire(periph) == CAM_REQ_CMP)
+ printf("Acquired periph Ok\n");
+ /*
+ * Add async callbacks for bus reset and
+ * bus device reset calls. I don't bother
+ * checking if this fails as, in most cases,
+ * the system will function just fine without
+ * them and the only alternative would be to
+ * not attach the device on failure.
+ */
+ xpt_register_async(AC_SENT_BDR | AC_BUS_RESET | AC_LOST_DEVICE |
+ AC_GETDEV_CHANGED | AC_ADVINFO_CHANGED,
+ sddaasync, periph, periph->path);
+
+// if (cam_periph_acquire(periph) != CAM_REQ_CMP)
+// printf("wtf?!");
+// else
+// xpt_schedule(periph, CAM_PRIORITY_DEV);
+ return(CAM_REQ_CMP);
+}
+
+static void
+sdda_start_init(struct cam_periph *periph, union ccb *start_ccb) {
+ struct sdda_softc *softc = (struct sdda_softc *)periph->softc;
+ //struct ccb_mmcio *mmcio = &start_ccb->mmcio;
+ struct mmc_params *mmcp = &periph->path->device->mmc_ident_data;
+ struct cam_ed *device = periph->path->device;
+
+ if (mmcp->card_features & CARD_FEATURE_MMC) {
+ mmc_decode_csd_mmc(mmcp->card_csd, &softc->csd);
+ mmc_decode_cid_mmc(mmcp->card_cid, &softc->cid);
+ } else {
+ mmc_decode_csd_sd(mmcp->card_csd, &softc->csd);
+ mmc_decode_cid_sd(mmcp->card_cid, &softc->cid);
+ }
+ mmc_format_card_id_string(softc, mmcp);
+
+
+ CAM_DEBUG(start_ccb->ccb_h.path, CAM_DEBUG_PERIPH,
+ ("Capacity: %"PRIu64", sectors: %"PRIu64"\n",
+ softc->csd.capacity,
+ softc->csd.capacity / 512));
+ softc->state = SDDA_STATE_NORMAL;
+
+ softc->sector_count = softc->csd.capacity / 512;
+ softc->mediasize = softc->csd.capacity;
+
+ /* Update info for CAM */
+ device->serial_num_len = strlen(softc->card_sn_string);
+ device->serial_num =
+ (u_int8_t *)malloc((device->serial_num_len + 1),
+ M_CAMXPT, M_NOWAIT);
+ strlcpy(device->serial_num, softc->card_sn_string, device->serial_num_len);
+
+ device->device_id_len = strlen(softc->card_id_string);
+ device->device_id =
+ (u_int8_t *)malloc((device->device_id_len + 1),
+ M_CAMXPT, M_NOWAIT);
+ strlcpy(device->device_id, softc->card_id_string, device->device_id_len);
+
+ strlcpy(mmcp->model, softc->card_id_string, sizeof(mmcp->model));
+ sdda_hook_into_geom(periph);
+ return;
+
+/* switch (softc->state) {
+ case SDDA_STATE_INIT:
+ {
+ start_ccb->ccb_h.func_code = XPT_MMC_IO;
+ start_ccb->ccb_h.flags = CAM_DIR_IN;
+ start_ccb->ccb_h.retry_count = 0;
+ start_ccb->ccb_h.timeout = 15 * 1000;
+ start_ccb->ccb_h.cbfcnp = sdda_done_init;
+
+ mmcio->cmd.opcode = MMC_SEND_CSD;
+ mmcio->cmd.arg = mmcp->card_rca << 16;
+ mmcio->cmd.flags = MMC_RSP_R2 | MMC_CMD_BCR;
+ mmcio->cmd.data = NULL;
+ break;
+ }
+ case SDDA_STATE_INVALID:
+ return;
+ default:
+ panic("Wrong state in sdda_start_init");
+ }
+
+ start_ccb->ccb_h.flags |= CAM_DEV_QFREEZE;
+ xpt_action(start_ccb);
+*/
+}
+
+/*static void
+sdda_done_init(struct cam_periph *periph, union ccb *done_ccb) {
+ struct sdda_softc *softc = (struct sdda_softc *)periph->softc;
+ struct ccb_mmcio *mmcio = &done_ccb->mmcio;
+// struct mmc_params *mmcp = &periph->path->device->mmc_ident_data;
+ struct cam_path *path = done_ccb->ccb_h.path;
+ int err = mmcio->cmd.error;
+ int priority = done_ccb->ccb_h.pinfo.priority;
+
+ switch (softc->state) {
+ case SDDA_STATE_INIT:
+ {
+ if (err != MMC_ERR_NONE) {
+ CAM_DEBUG(done_ccb->ccb_h.path, CAM_DEBUG_PERIPH,
+ ("Failed to get CSD\n"));
+ break;
+ }
+ memcpy(softc->raw_csd, mmcio->cmd.resp, 4 * sizeof(uint32_t));
+ CAM_DEBUG(done_ccb->ccb_h.path, CAM_DEBUG_PERIPH,
+ ("CSD: %08x %08x %08x %08x\n",
+ softc->raw_csd[0],
+ softc->raw_csd[1],
+ softc->raw_csd[2],
+ softc->raw_csd[3]));
+ mmc_decode_csd_sd(softc->raw_csd, &softc->csd);
+ CAM_DEBUG(done_ccb->ccb_h.path, CAM_DEBUG_PERIPH,
+ ("Capacity: %llu, sectors: %llu\n",
+ softc->csd.capacity,
+ softc->csd.capacity / 512));
+ softc->state = SDDA_STATE_INVALID;
+ break;
+ }
+ default:
+ panic("Wrong state in sdda_done_init");
+ }
+
+ xpt_release_ccb(done_ccb);
+ xpt_schedule(periph, priority);
+ cam_release_devq(path, 0, 0, 0, FALSE);
+}
+*/
+/* Called with periph lock held! */
+static void
+sddastart(struct cam_periph *periph, union ccb *start_ccb)
+{
+ struct sdda_softc *softc = (struct sdda_softc *)periph->softc;
+ struct mmc_params *mmcp = &periph->path->device->mmc_ident_data;
+
+ CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, ("sddastart\n"));
+
+ if (softc->state != SDDA_STATE_NORMAL) {
+ sdda_start_init(periph, start_ccb);
+ return;
+ }
+ struct bio *bp;
+
+ /* Run regular command. */
+ bp = bioq_first(&softc->bio_queue);
+ if (bp == NULL) {
+ xpt_release_ccb(start_ccb);
+ return;
+ }
+ bioq_remove(&softc->bio_queue, bp);
+
+ switch (bp->bio_cmd) {
+ case BIO_WRITE:
+ CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, ("BIO_WRITE\n"));
+ softc->flags |= SDDA_FLAG_DIRTY;
+ /* FALLTHROUGH */
+ case BIO_READ:
+ {
+ CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, ("BIO_READ\n"));
+ uint64_t blockno = bp->bio_pblkno;
+ uint16_t count = bp->bio_bcount / 512;
+ uint16_t opcode;
+
+ CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, ("Block %"PRIu64" cnt %u\n", blockno, count));
+
+ /* Construct new MMC command */
+ if (bp->bio_cmd == BIO_READ) {
+ if (count > 1)
+ opcode = MMC_READ_MULTIPLE_BLOCK;
+ else
+ opcode = MMC_READ_SINGLE_BLOCK;
+ } else {
+ if (count > 1)
+ opcode = MMC_WRITE_MULTIPLE_BLOCK;
+ else
+ opcode = MMC_WRITE_BLOCK;
+ }
+
+ start_ccb->ccb_h.func_code = XPT_MMC_IO;
+ start_ccb->ccb_h.flags = (bp->bio_cmd == BIO_READ ? CAM_DIR_IN : CAM_DIR_OUT);
+ start_ccb->ccb_h.retry_count = 0;
+ start_ccb->ccb_h.timeout = 15 * 1000;
+ start_ccb->ccb_h.cbfcnp = sddadone;
+ struct ccb_mmcio *mmcio;
+
+ mmcio = &start_ccb->mmcio;
+ mmcio->cmd.opcode = opcode;
+ mmcio->cmd.arg = blockno;
+ if (!(mmcp->card_features & CARD_FEATURE_SDHC))
+ mmcio->cmd.arg <<= 9;
+
+ mmcio->cmd.flags = MMC_RSP_R1 | MMC_CMD_ADTC;
+ mmcio->cmd.data.data = bp->bio_data;
+ mmcio->cmd.data.len = 512 * count;
+ mmcio->cmd.data.flags = (bp->bio_cmd == BIO_READ ? MMC_DATA_READ : MMC_DATA_WRITE);
+ /* Direct h/w to issue CMD12 upon completion */
+ if (count > 1) {
+ mmcio->stop.opcode = MMC_STOP_TRANSMISSION;
+ mmcio->stop.flags = MMC_RSP_R1B | MMC_CMD_AC;
+ mmcio->stop.arg = 0;
+ }
+
+ break;
+ }
+ case BIO_FLUSH:
+ CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, ("BIO_FLUSH\n"));
+ sddaschedule(periph);
+ break;
+ case BIO_DELETE:
+ CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, ("BIO_DELETE\n"));
+ sddaschedule(periph);
+ break;
+ }
+
+ start_ccb->ccb_h.ccb_bp = bp;
+ softc->outstanding_cmds++;
+ softc->refcount++;
+ cam_periph_unlock(periph);
+ xpt_action(start_ccb);
+ cam_periph_lock(periph);
+ softc->refcount--;
+
+ /* May have more work to do, so ensure we stay scheduled */
+ sddaschedule(periph);
+}
+
+static void
+sddadone(struct cam_periph *periph, union ccb *done_ccb)
+{
+ struct sdda_softc *softc;
+ struct ccb_mmcio *mmcio;
+// struct ccb_getdev *cgd;
+ struct cam_path *path;
+// int state;
+
+ softc = (struct sdda_softc *)periph->softc;
+ mmcio = &done_ccb->mmcio;
+ path = done_ccb->ccb_h.path;
+
+ CAM_DEBUG(path, CAM_DEBUG_TRACE, ("sddadone\n"));
+
+ struct bio *bp;
+ int error = 0;
+
+// cam_periph_lock(periph);
+ if ((done_ccb->ccb_h.status & CAM_STATUS_MASK) != CAM_REQ_CMP) {
+ CAM_DEBUG(path, CAM_DEBUG_TRACE, ("Error!!!\n"));
+ if ((done_ccb->ccb_h.status & CAM_DEV_QFRZN) != 0)
+ cam_release_devq(path,
+ /*relsim_flags*/0,
+ /*reduction*/0,
+ /*timeout*/0,
+ /*getcount_only*/0);
+ error = 5; /* EIO */
+ } else {
+ if ((done_ccb->ccb_h.status & CAM_DEV_QFRZN) != 0)
+ panic("REQ_CMP with QFRZN");
+ error = 0;
+ }
+
+
+ bp = (struct bio *)done_ccb->ccb_h.ccb_bp;
+ bp->bio_error = error;
+ if (error != 0) {
+ bp->bio_resid = bp->bio_bcount;
+ bp->bio_flags |= BIO_ERROR;
+ } else {
+ /* XXX: How many bytes remaining? */
+ bp->bio_resid = 0;
+ if (bp->bio_resid > 0)
+ bp->bio_flags |= BIO_ERROR;
+ }
+
+ uint32_t card_status = mmcio->cmd.resp[0];
+ CAM_DEBUG(path, CAM_DEBUG_TRACE,
+ ("Card status: %08x\n", R1_STATUS(card_status)));
+ CAM_DEBUG(path, CAM_DEBUG_TRACE,
+ ("Current state: %d\n", R1_CURRENT_STATE(card_status)));
+
+ softc->outstanding_cmds--;
+ xpt_release_ccb(done_ccb);
+// cam_periph_unlock(periph);
+ biodone(bp);
+}
+
+static int
+sddaerror(union ccb *ccb, u_int32_t cam_flags, u_int32_t sense_flags)
+{
+ return(cam_periph_error(ccb, cam_flags, sense_flags, NULL));
+}
+
+/*
+ * Step through all SDDA peripheral drivers, and if the device is still open,
+ * sync the disk cache to physical media.
+ */
+static void
+sddaflush(void)
+{
+ struct cam_periph *periph;
+// struct sdda_softc *softc;
+// union ccb *ccb;
+// int error;
+
+ CAM_PERIPH_FOREACH(periph, &sddadriver) {
+ cam_periph_lock(periph);
+ xpt_print(periph->path, "flush\n");
+ cam_periph_unlock(periph);
+ }
+}
+
+static void
+sddaspindown(uint8_t cmd, int flags)
+{
+ struct cam_periph *periph;
+
+ CAM_PERIPH_FOREACH(periph, &sddadriver) {
+ cam_periph_lock(periph);
+ xpt_print(periph->path, "spin-down\n");
+ cam_periph_unlock(periph);
+ }
+}
+
+#endif /* _KERNEL */
Now, this is one of the most important file. It provides all device specific functions that takes a CCB, extracts SCSI command and convert it into hardware specific commands. It provides functions to decode the command into expected SD card/ MMC register contents.
Before moving forward, lets have a look at different registers of sd card/mmc:
There are total 8 sd card registers out of which only 6 are common with mmc. Refer https://www.kingston.com/datasheets/SDCIT-specsheet-64gb_en.pdf and this for detailed overview.
First 6 registers are common with MMC.
OCR register describes operating voltage, card power up state and power supply status bits.
CID Card Identification Register, contains vendor specific information about the sd card/mmc. It contains manufacturer id, product name, product serial number etc.
CSD(Card specific data register) contains all card related technical details like maximum data transfer rate, Data read access time, write speed factor etc. It is configurable.
RCA Register- The writable 16bit relative card address register carries the card address in SD Card mode.
SCR (SD Card Configuration Register) provides information on the SD memory card’s special features.
DSR (Driver Stage Register) an be optionally used to improve the bus performance for extended operating conditions (depending on parameters like bus length, transfer rate or number of cards). The CSD register carries the information about the DSR register usage. The default value of the DSR register is 0x404.
Moving back towards understanding mmc_da.c, first structure to encounter is sdda_softc it contains various hardware specific parameters like sector count ,media size etc. Then there is get_rca function which retrieves the RCA register content. Notice the path carefully(periph->path->device->mmc_ident_data.card_rca)!
+get_rca(struct cam_periph *periph) {
+ return periph->path->device->mmc_ident_data.card_rca;
+}Then there is, mmc_decode_csd_sd function that takes raw csd register data, decode it and fill it in mmc_csd structure which is passed on to this function as it's second argument. Have a look at page 88 of this it explains various csd version register structures. Version 0 corresponds to standard capacity sd cards while version 1 corresponds to high capacity sd cards. Version 2 and 3 are still reserved for upcoming versions. Similarly, we have mmc_decode_cid_mmc function which decodes cid register data and stores it in a structure. Function mmc_format_card_id_string formats the SD-card/MMC id which will be used for its identification.
Then we have, sddaschedule which calls xpt_schedule() if device is already in the queue.
+static void
+sddaschedule(struct cam_periph *periph)
+{
+ struct sdda_softc *softc = (struct sdda_softc *)periph->softc;
+
+ /* Check if we have more work to do. */
+ if (bioq_first(&softc->bio_queue)) {
+ xpt_schedule(periph, CAM_PRIORITY_NORMAL);
+ }
+}
xpt_schedule schedules/prepares the peripheral module to recieve the CAM control block (CCB). It then calls xpt_run_dev_allocq which allocates and constructs the CCB. We will look at it in detail, in a later section.
And now we have our star function, sddastrategy
+static void
+sddastrategy(struct bio *bp)
+{
+ struct cam_periph *periph;
+ struct sdda_softc *softc;
+
+ periph = (struct cam_periph *)bp->bio_disk->d_drv1;
+ softc = (struct sdda_softc *)periph->softc;
+
+ cam_periph_lock(periph);
+
+ CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, ("sddastrategy(%p)\n", bp));
+
+ /*
+ * If the device has been made invalid, error out
+ */
+ if ((periph->flags & CAM_PERIPH_INVALID) != 0) {
+ cam_periph_unlock(periph);
+ biofinish(bp, NULL, ENXIO);
+ return;
+ }
+
+ /*
+ * Place it in the queue of disk activities for this disk
+ */
+ bioq_disksort(&softc->bio_queue, bp);
+
+ /*
+ * Schedule ourselves for performing the work.
+ */
+ sddaschedule(periph);
+ cam_periph_unlock(periph);
+
+ return;
+}
+
This function is the first one to be called for handling the I/O request by OS. It makes up the CAM peripheral module layer. So, the first thing it does is, bioq_disksort which places the I/O request in the queue. Maintaining a queue is very necessary as to avoid overloading the SIM with requests. Queue can have only a fixed number of CCBs and each executes in an order. It then calls sddaschedule which in turn calls xpt_schedule.
Then, next function we see is sddainit which does some rudimentary initialization before sddastrategy. Then we have sddadiskgonecb ; After sending the CCB to SIM program execution is returned to the caller of sddastrategy but before that sddacleanup is used to cleanup all redundant data and then sddadiskgonecb is called.
Then we have sddaasync function that handles all asynchronous interrupts from CAM bus. Following is the types of asynchronous calls:
/*
* Definitions for the asynchronous callback CCB fields.
*/
typedef enum {
AC_UNIT_ATTENTION = 0x4000,/* Device reported UNIT ATTENTION */
AC_ADVINFO_CHANGED = 0x2000,/* Advance info might have changes */
AC_CONTRACT = 0x1000,/* A contractual callback */
AC_GETDEV_CHANGED = 0x800,/* Getdev info might have changed */
AC_INQ_CHANGED = 0x400,/* Inquiry info might have changed */
AC_TRANSFER_NEG = 0x200,/* New transfer settings in effect */
AC_LOST_DEVICE = 0x100,/* A device went away */
AC_FOUND_DEVICE = 0x080,/* A new device was found */
AC_PATH_DEREGISTERED = 0x040,/* A path has de-registered */
AC_PATH_REGISTERED = 0x020,/* A new path has been registered */
AC_SENT_BDR = 0x010,/* A BDR message was sent to target */
AC_SCSI_AEN = 0x008,/* A SCSI AEN has been received */
AC_UNSOL_RESEL = 0x002,/* Unsolicited reselection occurred */
AC_BUS_RESET = 0x001 /* A SCSI bus reset occurred */
} ac_code;
and in the function sddaasync notice the switch case statement that handles all these events:
+static void
+sddaasync(void *callback_arg, u_int32_t code,
+ struct cam_path *path, void *arg)
+{
+ struct ccb_getdev cgd;
+ struct cam_periph *periph;
+ struct sdda_softc *softc;
+
+ periph = (struct cam_periph *)callback_arg;
+ CAM_DEBUG(path, CAM_DEBUG_TRACE, ("sddaasync(code=%d)\n", code));
+ switch (code) {
+ case AC_FOUND_DEVICE:
+ {
+ CAM_DEBUG(path, CAM_DEBUG_TRACE, ("=> AC_FOUND_DEVICE\n"));
+ struct ccb_getdev *cgd;
+ cam_status status;
+
+ cgd = (struct ccb_getdev *)arg;
+ if (cgd == NULL)
+ break;
+
+ if (cgd->protocol != PROTO_MMCSD)
+ break;
+
+ if (!(path->device->mmc_ident_data.card_features & CARD_FEATURE_MEMORY)) {
+ CAM_DEBUG(path, CAM_DEBUG_TRACE, ("No memory on the card!\n"));
+ break;
+ }
+
+ /*
+ * Allocate a peripheral instance for
+ * this device and start the probe
+ * process.
+ */
+ status = cam_periph_alloc(sddaregister, sddaoninvalidate,
+ sddacleanup, sddastart,
+ "sdda", CAM_PERIPH_BIO,
+ path, sddaasync,
+ AC_FOUND_DEVICE, cgd);
+
+ if (status != CAM_REQ_CMP
+ && status != CAM_REQ_INPROG)
+ printf("sddaasync: Unable to attach to new device "
+ "due to status 0x%x\n", status);
+ break;
+ }
+ case AC_GETDEV_CHANGED:
+ {
+ CAM_DEBUG(path, CAM_DEBUG_TRACE, ("=> AC_GETDEV_CHANGED\n"));
+ softc = (struct sdda_softc *)periph->softc;
+ xpt_setup_ccb(&cgd.ccb_h, periph->path, CAM_PRIORITY_NORMAL);
+ cgd.ccb_h.func_code = XPT_GDEV_TYPE;
+ xpt_action((union ccb *)&cgd);
+ cam_periph_async(periph, code, path, arg);
+ break;
+ }
+ case AC_ADVINFO_CHANGED:
+ {
+ uintptr_t buftype;
+ CAM_DEBUG(path, CAM_DEBUG_TRACE, ("=> AC_ADVINFO_CHANGED\n"));
+ buftype = (uintptr_t)arg;
+ if (buftype == CDAI_TYPE_PHYS_PATH) {
+ struct sdda_softc *softc;
+
+ softc = periph->softc;
+ disk_attr_changed(softc->disk, "GEOM::physpath",
+ M_NOWAIT);
+ }
+ break;
+ }
+ case AC_SENT_BDR:
+ case AC_BUS_RESET:
+ {
+ CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, ("AC_BUS_RESET"));
+ }
+ default:
+ CAM_DEBUG(path, CAM_DEBUG_TRACE, ("=> default?!\n"));
+ cam_periph_async(periph, code, path, arg);
+ break;
+ }
+}
Notice that in case of hot plug/unplug event there will be an async. interrupt that will be handeled by bove function. Then we have mmc_set_timming() which sets the clock frequency of sd-card/mmc. It also determines whether a device supports high speed mode or not and sets the clock frequency accordingly.
+static void
+sdda_start_init_task(void *context, int pending) {
+ union ccb *new_ccb;
+ struct cam_periph *periph;
+
+ periph = (struct cam_periph *)context;
+ CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, ("sdda_start_init_task\n"));
+ new_ccb = xpt_alloc_ccb();
+ xpt_setup_ccb(&new_ccb->ccb_h, periph->path,
+ CAM_PRIORITY_NONE);
+
+ cam_periph_lock(periph);
+ sdda_start_init(context, new_ccb);
+ cam_periph_unlock(periph);
+ xpt_free_ccb(new_ccb);
+}
sdda_start_init_task allocates and initializes a new CCB block with the received context (I/O request) this will be called after xpt_schedule.
sdda_set_bus_width as its name suggests sets the bus width.
sdda_start_init initializes the new CCB block made by sdda_start_init_task. It performs CID and CSD register check and extract all relevant data which is stored in CCB.
Then we have sddastart(), which is called after xpt_run_alloq_dev. It is the peripheral module start routine which takes a I/O command and convert it into SCSI command.
static void
+sddastart(struct cam_periph *periph, union ccb *start_ccb)
+{
+ struct sdda_softc *softc = (struct sdda_softc *)periph->softc;
+ struct mmc_params *mmcp = &periph->path->device->mmc_ident_data;
+
+ CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, ("sddastart\n"));
+
+ if (softc->state != SDDA_STATE_NORMAL) {
+ CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, ("device is not in SDDA_STATE_NORMAL yet"));
+ xpt_release_ccb(start_ccb);
+ return;
+ }
+ struct bio *bp;
+
+ /* Run regular command. */
+ bp = bioq_first(&softc->bio_queue);
+ if (bp == NULL) {
+ xpt_release_ccb(start_ccb);
+ return;
+ }
+ bioq_remove(&softc->bio_queue, bp);
+
+ switch (bp->bio_cmd) {
+ case BIO_WRITE:
+ CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, ("BIO_WRITE\n"));
+ softc->flags |= SDDA_FLAG_DIRTY;
+ /* FALLTHROUGH */
+ case BIO_READ:
+ {
+ CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, ("BIO_READ\n"));
+ uint64_t blockno = bp->bio_pblkno;
+ uint16_t count = bp->bio_bcount / 512;
+ uint16_t opcode;
+
+ CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, ("Block %"PRIu64" cnt %u\n", blockno, count));
+
+ /* Construct new MMC command */
+ if (bp->bio_cmd == BIO_READ) {
+ if (count > 1)
+ opcode = MMC_READ_MULTIPLE_BLOCK;
+ else
+ opcode = MMC_READ_SINGLE_BLOCK;
+ } else {
+ if (count > 1)
+ opcode = MMC_WRITE_MULTIPLE_BLOCK;
+ else
+ opcode = MMC_WRITE_BLOCK;
+ }
+
+ start_ccb->ccb_h.func_code = XPT_MMC_IO;
+ start_ccb->ccb_h.flags = (bp->bio_cmd == BIO_READ ? CAM_DIR_IN : CAM_DIR_OUT);
+ start_ccb->ccb_h.retry_count = 0;
+ start_ccb->ccb_h.timeout = 15 * 1000;
+ start_ccb->ccb_h.cbfcnp = sddadone;
+ struct ccb_mmcio *mmcio;
+
+ mmcio = &start_ccb->mmcio;
+ mmcio->cmd.opcode = opcode;
+ mmcio->cmd.arg = blockno;
+ if (!(mmcp->card_features & CARD_FEATURE_SDHC))
+ mmcio->cmd.arg <<= 9;
+
+ mmcio->cmd.flags = MMC_RSP_R1 | MMC_CMD_ADTC;
+ mmcio->cmd.data = softc->mmcdata;
+ mmcio->cmd.data->data = bp->bio_data;
+ mmcio->cmd.data->len = 512 * count;
+ mmcio->cmd.data->flags = (bp->bio_cmd == BIO_READ ? MMC_DATA_READ : MMC_DATA_WRITE);
+ /* Direct h/w to issue CMD12 upon completion */
+ if (count > 1) {
+ mmcio->stop.opcode = MMC_STOP_TRANSMISSION;
+ mmcio->stop.flags = MMC_RSP_R1B | MMC_CMD_AC;
+ mmcio->stop.arg = 0;
+ }
+
+ break;
+ }
+ case BIO_FLUSH:
+ CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, ("BIO_FLUSH\n"));
+ sddaschedule(periph);
+ break;
+ case BIO_DELETE:
+ CAM_DEBUG(periph->path, CAM_DEBUG_TRACE, ("BIO_DELETE\n"));
+ sddaschedule(periph);
+ break;
+ }
+ start_ccb->ccb_h.ccb_bp = bp;
+ softc->outstanding_cmds++;
+ softc->refcount++;
+ cam_periph_unlock(periph);
+ xpt_action(start_ccb);
+ cam_periph_lock(periph);
+ softc->refcount--;
+
+ /* May have more work to do, so ensure we stay scheduled */
+ sddaschedule(periph);
+}
Notice the switch case statement that converts a command to a more specific SCSI command. For example, BIO_READ is a command to read data from sd/mmc, it after considering the amount of data to be read is converted into MMC_READ_MULTIPLE_BLOCK or MMC_READ_SINGLE_BLOCK. It further performs other functions like flush, delete etc.
sddadone and sddaerr functions will be called by SIM after it completes it's requested operation. Status is stored and checked to raise an alert if unsuccessful.
Other then this file, there are other files that were also changed. W'll look into then into my next post.
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