It looks good to me.
Acked-by: Jaehoon Chung jh80.chung@samsung.com
On 01/29/2013 11:47 PM, Lukasz Majewski wrote:
Dear All,
Any feedback about this patch?
This patch changes sdhci_init()'s behavior to NOT enable all interrupt sources by default. Moreover interrupt signaling has been disabled.
This patch do not enable interrupts which aren't served in u-boot (they are defined at sdhci.h but NOT used elsewhere):
- SDHCI_INT_CARD_INSERT, SDHCI_INT_CARD_REMOVE, SDHCI_BUS_POWER, SDHCI_INT_CARD_REMOVE, SDHCI_INT_CARD_INT
Special care shall be put on SDHCI_INT_CARD_INT, which indicates interrupt generated by SD card. According to "SD Host Controller Simplified Spec. ver 3.00" when bit 8 (Card Interrupt Status Enable) at "Normal Interrupt Status Enable Register" (offset 0x34) is set, the card interrupt detection is started. Then eMMC card may cause the SD controller to set this bit and then this interrupt is passed to booted OS and might cause kernel crash.
To sum up:
- Only enable interrupts, which are served at u-boot
- This cleanup as a side effect fixes SDHCI's CARD INTERRUPT problem
at Linux kernel (versions 3.6+, sdhci controller)
- Keep masked bits at "Normal Interrupt Signal Enable
Register" (0x38h)
Signed-off-by: Lukasz Majewski l.majewski@samsung.com Signed-off-by: Kyungmin Park kyungmin.park@samsung.com Cc: Lei Wen leiwen@marvell.com Cc: Andy Fleming afleming@freescale.com
drivers/mmc/sdhci.c | 8 +++++--- 1 files changed, 5 insertions(+), 3 deletions(-)
diff --git a/drivers/mmc/sdhci.c b/drivers/mmc/sdhci.c index 0fd1337..76c14fb 100644 --- a/drivers/mmc/sdhci.c +++ b/drivers/mmc/sdhci.c @@ -412,9 +412,11 @@ int sdhci_init(struct mmc *mmc) status = sdhci_readl(host, SDHCI_PRESENT_STATE); }
- /* Eable all state */
- sdhci_writel(host, SDHCI_INT_ALL_MASK, SDHCI_INT_ENABLE);
- sdhci_writel(host, SDHCI_INT_ALL_MASK, SDHCI_SIGNAL_ENABLE);
/* Enable only interrupts served by the SD controller */
sdhci_writel(host, SDHCI_INT_DATA_MASK | SDHCI_INT_CMD_MASK
, SDHCI_INT_ENABLE);/* Mask all sdhci interrupt sources */
sdhci_writel(host, 0x0, SDHCI_SIGNAL_ENABLE);
return 0;
}