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mmc: sdhci-iproc: fix 32bit writes for TRANSFER_MODE register

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commit 5f651b870485ee60f5abbbd85195a6852978894a upstream.

When the host controller accepts only 32bit writes, the value of the
16bit TRANSFER_MODE register, that has the same 32bit address as the
16bit COMMAND register, needs to be saved and it will be written
in a 32bit write together with the command as this will trigger the
host to send the command on the SD interface.
When sending the tuning command, TRANSFER_MODE is written and then
sdhci_set_transfer_mode reads it back to clear AUTO_CMD12 bit and
write it again resulting in wrong value to be written because the
initial write value was saved in a shadow and the read-back returned
a wrong value, from the register.
Fix sdhci_iproc_readw to return the saved value of TRANSFER_MODE
when a saved value exist.
Same fix for read of BLOCK_SIZE and BLOCK_COUNT registers, that are
saved for a different reason, although a scenario that will cause the
mentioned problem on this registers is not probable.

Fixes: b580c52d58d9 ("mmc: sdhci-iproc: add IPROC SDHCI driver")
Signed-off-by: Corneliu Doban <corneliu.doban@broadcom.com>
Signed-off-by: Scott Branden <scott.branden@broadcom.com>
Cc: stable@vger.kernel.org # v4.1+
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Corneliu Doban 2018-05-18 15:03:56 -07:00 committed by Greg Kroah-Hartman
parent ebedf0b290
commit 4da8f20a99
1 changed files with 25 additions and 5 deletions
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30
drivers/mmc/host/sdhci-iproc.c
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@ -33,6 +33,8 @@ struct sdhci_iproc_host {
const struct sdhci_iproc_data *data;
u32 shadow_cmd;
u32 shadow_blk;
bool is_cmd_shadowed;
bool is_blk_shadowed;
};
#define REG_OFFSET_IN_BITS(reg) ((reg) << 3 & 0x18)
@ -48,8 +50,22 @@ static inline u32 sdhci_iproc_readl(struct sdhci_host *host, int reg)
static u16 sdhci_iproc_readw(struct sdhci_host *host, int reg)
{
u32 val = sdhci_iproc_readl(host, (reg & ~3));
u16 word = val >> REG_OFFSET_IN_BITS(reg) & 0xffff;
struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
struct sdhci_iproc_host *iproc_host = sdhci_pltfm_priv(pltfm_host);
u32 val;
u16 word;
if ((reg == SDHCI_TRANSFER_MODE) && iproc_host->is_cmd_shadowed) {
/* Get the saved transfer mode */
val = iproc_host->shadow_cmd;
} else if ((reg == SDHCI_BLOCK_SIZE || reg == SDHCI_BLOCK_COUNT) &&
iproc_host->is_blk_shadowed) {
/* Get the saved block info */
val = iproc_host->shadow_blk;
} else {
val = sdhci_iproc_readl(host, (reg & ~3));
}
word = val >> REG_OFFSET_IN_BITS(reg) & 0xffff;
return word;
}
@ -105,13 +121,15 @@ static void sdhci_iproc_writew(struct sdhci_host *host, u16 val, int reg)
if (reg == SDHCI_COMMAND) {
/* Write the block now as we are issuing a command */
if (iproc_host->shadow_blk != 0) {
if (iproc_host->is_blk_shadowed) {
sdhci_iproc_writel(host, iproc_host->shadow_blk,
SDHCI_BLOCK_SIZE);
iproc_host->shadow_blk = 0;
iproc_host->is_blk_shadowed = false;
}
oldval = iproc_host->shadow_cmd;
} else if (reg == SDHCI_BLOCK_SIZE || reg == SDHCI_BLOCK_COUNT) {
iproc_host->is_cmd_shadowed = false;
} else if ((reg == SDHCI_BLOCK_SIZE || reg == SDHCI_BLOCK_COUNT) &&
iproc_host->is_blk_shadowed) {
/* Block size and count are stored in shadow reg */
oldval = iproc_host->shadow_blk;
} else {
@ -123,9 +141,11 @@ static void sdhci_iproc_writew(struct sdhci_host *host, u16 val, int reg)
if (reg == SDHCI_TRANSFER_MODE) {
/* Save the transfer mode until the command is issued */
iproc_host->shadow_cmd = newval;
iproc_host->is_cmd_shadowed = true;
} else if (reg == SDHCI_BLOCK_SIZE || reg == SDHCI_BLOCK_COUNT) {
/* Save the block info until the command is issued */
iproc_host->shadow_blk = newval;
iproc_host->is_blk_shadowed = true;
} else {
/* Command or other regular 32-bit write */
sdhci_iproc_writel(host, newval, reg & ~3);