mmc: add a function to read and test the ext csd (mmc >= 4)
This will be reused later in the selection of high speed and ddr modes.
Signed-off-by: Jean-Jacques Hiblot <jjhiblot@ti.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c
index 694091d..c4067e2 100644
--- a/drivers/mmc/mmc.c
+++ b/drivers/mmc/mmc.c
@@ -1146,10 +1146,39 @@
return 0;
}
+/*
+ * read the compare the part of ext csd that is constant.
+ * This can be used to check that the transfer is working
+ * as expected.
+ */
+static int mmc_read_and_compare_ext_csd(struct mmc *mmc)
+{
+ int err;
+ const u8 *ext_csd = mmc->ext_csd;
+ ALLOC_CACHE_ALIGN_BUFFER(u8, test_csd, MMC_MAX_BLOCK_LEN);
+
+ err = mmc_send_ext_csd(mmc, test_csd);
+ if (err)
+ return err;
+
+ /* Only compare read only fields */
+ if (ext_csd[EXT_CSD_PARTITIONING_SUPPORT]
+ == test_csd[EXT_CSD_PARTITIONING_SUPPORT] &&
+ ext_csd[EXT_CSD_HC_WP_GRP_SIZE]
+ == test_csd[EXT_CSD_HC_WP_GRP_SIZE] &&
+ ext_csd[EXT_CSD_REV]
+ == test_csd[EXT_CSD_REV] &&
+ ext_csd[EXT_CSD_HC_ERASE_GRP_SIZE]
+ == test_csd[EXT_CSD_HC_ERASE_GRP_SIZE] &&
+ memcmp(&ext_csd[EXT_CSD_SEC_CNT],
+ &test_csd[EXT_CSD_SEC_CNT], 4) == 0)
+ return 0;
+
+ return -EBADMSG;
+}
+
static int mmc_select_bus_freq_width(struct mmc *mmc)
{
- ALLOC_CACHE_ALIGN_BUFFER(u8, test_csd, MMC_MAX_BLOCK_LEN);
- const u8 *ext_csd = mmc->ext_csd;
/* An array of possible bus widths in order of preference */
static const unsigned int ext_csd_bits[] = {
EXT_CSD_DDR_BUS_WIDTH_8,
@@ -1221,25 +1250,9 @@
mmc->ddr_mode = (caps & MMC_MODE_DDR_52MHz) ? 1 : 0;
mmc_set_bus_width(mmc, widths[idx]);
- err = mmc_send_ext_csd(mmc, test_csd);
-
- if (err)
- continue;
-
- /* Only compare read only fields */
- if (ext_csd[EXT_CSD_PARTITIONING_SUPPORT]
- == test_csd[EXT_CSD_PARTITIONING_SUPPORT] &&
- ext_csd[EXT_CSD_HC_WP_GRP_SIZE]
- == test_csd[EXT_CSD_HC_WP_GRP_SIZE] &&
- ext_csd[EXT_CSD_REV]
- == test_csd[EXT_CSD_REV] &&
- ext_csd[EXT_CSD_HC_ERASE_GRP_SIZE]
- == test_csd[EXT_CSD_HC_ERASE_GRP_SIZE] &&
- memcmp(&ext_csd[EXT_CSD_SEC_CNT],
- &test_csd[EXT_CSD_SEC_CNT], 4) == 0)
+ err = mmc_read_and_compare_ext_csd(mmc);
+ if (!err)
break;
-
- err = -EBADMSG;
}
if (err)