SD/MMC patches

- Fix a bug in CMD6/SWITCH_FUNCTION (Bin Meng)
 - Minor housekeeping patches
 
 CI jobs result:
 . https://cirrus-ci.com/build/5461987880599552
 . https://gitlab.com/philmd/qemu/-/pipelines/207532287
 . https://travis-ci.org/github/philmd/qemu/builds/738901111
 . https://app.shippable.com/github/philmd/qemu/runs/888/summary/console
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Merge remote-tracking branch 'remotes/philmd-gitlab/tags/sd-next-20201026' into staging

SD/MMC patches

- Fix a bug in CMD6/SWITCH_FUNCTION (Bin Meng)
- Minor housekeeping patches

CI jobs result:
. https://cirrus-ci.com/build/5461987880599552
. https://gitlab.com/philmd/qemu/-/pipelines/207532287
. https://travis-ci.org/github/philmd/qemu/builds/738901111
. https://app.shippable.com/github/philmd/qemu/runs/888/summary/console

# gpg: Signature made Mon 26 Oct 2020 11:02:22 GMT
# gpg:                using RSA key FAABE75E12917221DCFD6BB2E3E32C2CDEADC0DE
# gpg: Good signature from "Philippe Mathieu-Daudé (F4BUG) <f4bug@amsat.org>" [full]
# Primary key fingerprint: FAAB E75E 1291 7221 DCFD  6BB2 E3E3 2C2C DEAD C0DE

* remotes/philmd-gitlab/tags/sd-next-20201026:
  hw/sd/sdcard: Zero out function selection fields before being populated
  hw/sd/sdcard: Make iolen unsigned
  hw/sd/sdcard: Constify sd_crc*()'s message argument
  hw/sd/sdcard: Simplify cmd_valid_while_locked()
  hw/sd/sdcard: Update the SDState documentation

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

hw/sd/sd.c

@@ -102,11 +102,14 @@ struct SDState {
     uint32_t card_status;
     uint8_t sd_status[64];
 
-    /* Configurable properties */
+    /* Static properties */
+
     uint8_t spec_version;
     BlockBackend *blk;
     bool spi;
 
+    /* Runtime changeables */
+
     uint32_t mode;    /* current card mode, one of SDCardModes */
     int32_t state;    /* current card state, one of SDCardStates */
     uint32_t vhs;
@@ -251,11 +254,11 @@ static const int sd_cmd_class[SDMMC_CMD_MAX] = {
     7,  7, 10,  7,  9,  9,  9,  8,  8, 10,  8,  8,  8,  8,  8,  8,
 };
 
-static uint8_t sd_crc7(void *message, size_t width)
+static uint8_t sd_crc7(const void *message, size_t width)
 {
     int i, bit;
     uint8_t shift_reg = 0x00;
-    uint8_t *msg = (uint8_t *) message;
+    const uint8_t *msg = (const uint8_t *)message;
 
     for (i = 0; i < width; i ++, msg ++)
         for (bit = 7; bit >= 0; bit --) {
@@ -267,11 +270,11 @@ static uint8_t sd_crc7(void *message, size_t width)
     return shift_reg;
 }
 
-static uint16_t sd_crc16(void *message, size_t width)
+static uint16_t sd_crc16(const void *message, size_t width)
 {
     int i, bit;
     uint16_t shift_reg = 0x0000;
-    uint16_t *msg = (uint16_t *) message;
+    const uint16_t *msg = (const uint16_t *)message;
     width <<= 1;
 
     for (i = 0; i < width; i ++, msg ++)
@@ -824,6 +827,7 @@ static void sd_function_switch(SDState *sd, uint32_t arg)
     sd->data[12] = 0x80;	/* Supported group 1 functions */
     sd->data[13] = 0x03;
 
+    memset(&sd->data[14], 0, 3);
     for (i = 0; i < 6; i ++) {
         new_func = (arg >> (i * 4)) & 0x0f;
         if (mode && new_func != 0x0f)
@@ -1676,7 +1680,7 @@ static sd_rsp_type_t sd_app_command(SDState *sd,
     return sd_illegal;
 }
 
-static int cmd_valid_while_locked(SDState *sd, SDRequest *req)
+static int cmd_valid_while_locked(SDState *sd, const uint8_t cmd)
 {
     /* Valid commands in locked state:
      * basic class (0)
@@ -1687,13 +1691,12 @@ static int cmd_valid_while_locked(SDState *sd, SDRequest *req)
      * Anything else provokes an "illegal command" response.
      */
     if (sd->expecting_acmd) {
-        return req->cmd == 41 || req->cmd == 42;
+        return cmd == 41 || cmd == 42;
     }
-    if (req->cmd == 16 || req->cmd == 55) {
+    if (cmd == 16 || cmd == 55) {
         return 1;
     }
-    return sd_cmd_class[req->cmd] == 0
+    return sd_cmd_class[cmd] == 0 || sd_cmd_class[cmd] == 7;
-            || sd_cmd_class[req->cmd] == 7;
 }
 
 int sd_do_command(SDState *sd, SDRequest *req,
@@ -1719,7 +1722,7 @@ int sd_do_command(SDState *sd, SDRequest *req,
     }
 
     if (sd->card_status & CARD_IS_LOCKED) {
-        if (!cmd_valid_while_locked(sd, req)) {
+        if (!cmd_valid_while_locked(sd, req->cmd)) {
             sd->card_status |= ILLEGAL_COMMAND;
             sd->expecting_acmd = false;
             qemu_log_mask(LOG_GUEST_ERROR, "SD: Card is locked\n");
@@ -1980,7 +1983,7 @@ uint8_t sd_read_byte(SDState *sd)
 {
     /* TODO: Append CRCs */
     uint8_t ret;
-    int io_len;
+    uint32_t io_len;
 
     if (!sd->blk || !blk_is_inserted(sd->blk) || !sd->enable)
         return 0x00;

hw/sd/trace-events

@@ -52,7 +52,7 @@ sdcard_unlock(void) ""
 sdcard_read_block(uint64_t addr, uint32_t len) "addr 0x%" PRIx64 " size 0x%x"
 sdcard_write_block(uint64_t addr, uint32_t len) "addr 0x%" PRIx64 " size 0x%x"
 sdcard_write_data(const char *proto, const char *cmd_desc, uint8_t cmd, uint8_t value) "%s %20s/ CMD%02d value 0x%02x"
-sdcard_read_data(const char *proto, const char *cmd_desc, uint8_t cmd, int length) "%s %20s/ CMD%02d len %d"
+sdcard_read_data(const char *proto, const char *cmd_desc, uint8_t cmd, uint32_t length) "%s %20s/ CMD%02d len %" PRIu32
 sdcard_set_voltage(uint16_t millivolts) "%u mV"
 
 # milkymist-memcard.c