[PATCH V4 4/7] mmc: sdhci: add 32-bit block count support for v4 mode

From: Chunyan Zhang
Date: Mon Jul 23 2018 - 22:51:30 EST


Host Controller Version 4.10 re-defines SDMA System Address register
as 32-bit Block Count for v4 mode, and SDMA uses ADMA System
Address register (05Fh-058h) instead if v4 mode is enabled. Also
when using 32-bit block count, 16-bit block count register need
to be set to zero.

Signed-off-by: Chunyan Zhang <zhang.chunyan@xxxxxxxxxx>
---
drivers/mmc/host/sdhci.c | 14 +++++++++++++-
drivers/mmc/host/sdhci.h | 1 +
2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 920d8ec..c272a2b 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -1070,7 +1070,19 @@ static void sdhci_prepare_data(struct sdhci_host *host, struct mmc_command *cmd)
/* Set the DMA boundary value and block size */
sdhci_writew(host, SDHCI_MAKE_BLKSZ(host->sdma_boundary, data->blksz),
SDHCI_BLOCK_SIZE);
- sdhci_writew(host, data->blocks, SDHCI_BLOCK_COUNT);
+
+ /*
+ * For Version 4.10 onwards, if v4 mode is enabled, 16-bit Block Count
+ * register need to be set to zero, 32-bit Block Count register would
+ * be selected.
+ */
+ if (host->version >= SDHCI_SPEC_410 && host->v4_mode) {
+ if (sdhci_readw(host, SDHCI_BLOCK_COUNT))
+ sdhci_writew(host, 0, SDHCI_BLOCK_COUNT);
+ sdhci_writew(host, data->blocks, SDHCI_32BIT_BLK_CNT);
+ } else {
+ sdhci_writew(host, data->blocks, SDHCI_BLOCK_COUNT);
+ }
}

static inline bool sdhci_auto_cmd12(struct sdhci_host *host,
diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
index 23318ff..81aae07 100644
--- a/drivers/mmc/host/sdhci.h
+++ b/drivers/mmc/host/sdhci.h
@@ -28,6 +28,7 @@

#define SDHCI_DMA_ADDRESS 0x00
#define SDHCI_ARGUMENT2 SDHCI_DMA_ADDRESS
+#define SDHCI_32BIT_BLK_CNT SDHCI_DMA_ADDRESS

#define SDHCI_BLOCK_SIZE 0x04
#define SDHCI_MAKE_BLKSZ(dma, blksz) (((dma & 0x7) << 12) | (blksz & 0xFFF))
--
2.7.4