From ce0c1bc13556fbf1bdfa2a4a27ca6744e7beb32a Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?=C5=81ukasz=20Majewski?= Date: Fri, 11 Jan 2013 05:08:54 +0000 Subject: [PATCH] mmc:sdhci:fix: Change default interrupts enabled at SDHCI initialization 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 Signed-off-by: Kyungmin Park Cc: Lei Wen Cc: Andy Fleming Acked-by: Jaehoon Chung Signed-off-by: Minkyu Kang --- drivers/mmc/sdhci.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/drivers/mmc/sdhci.c b/drivers/mmc/sdhci.c index b9cbe34..551b423 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; }