From 5ef1ecf060f28ecef313b5723f1fd39bf5a35f56 Mon Sep 17 00:00:00 2001 From: Heiner Kallweit Date: Wed, 29 Mar 2017 20:54:37 +0200 Subject: [PATCH 1/3] mmc: sdio: fix alignment issue in struct sdio_func Certain 64-bit systems (e.g. Amlogic Meson GX) require buffers to be used for DMA to be 8-byte-aligned. struct sdio_func has an embedded small DMA buffer not meeting this requirement. When testing switching to descriptor chain mode in meson-gx driver SDIO is broken therefore. Fix this by allocating the small DMA buffer separately as kmalloc ensures that the returned memory area is properly aligned for every basic data type. Signed-off-by: Heiner Kallweit Tested-by: Helmut Klein Signed-off-by: Ulf Hansson --- drivers/mmc/core/sdio_bus.c | 12 +++++++++++- include/linux/mmc/sdio_func.h | 2 +- 2 files changed, 12 insertions(+), 2 deletions(-) diff --git a/drivers/mmc/core/sdio_bus.c b/drivers/mmc/core/sdio_bus.c index e992a7f8a16fc..2b32b88949ba4 100644 --- a/drivers/mmc/core/sdio_bus.c +++ b/drivers/mmc/core/sdio_bus.c @@ -267,7 +267,7 @@ static void sdio_release_func(struct device *dev) sdio_free_func_cis(func); kfree(func->info); - + kfree(func->tmpbuf); kfree(func); } @@ -282,6 +282,16 @@ struct sdio_func *sdio_alloc_func(struct mmc_card *card) if (!func) return ERR_PTR(-ENOMEM); + /* + * allocate buffer separately to make sure it's properly aligned for + * DMA usage (incl. 64 bit DMA) + */ + func->tmpbuf = kmalloc(4, GFP_KERNEL); + if (!func->tmpbuf) { + kfree(func); + return ERR_PTR(-ENOMEM); + } + func->card = card; device_initialize(&func->dev); diff --git a/include/linux/mmc/sdio_func.h b/include/linux/mmc/sdio_func.h index aab032a6ae612..97ca105347a6c 100644 --- a/include/linux/mmc/sdio_func.h +++ b/include/linux/mmc/sdio_func.h @@ -53,7 +53,7 @@ struct sdio_func { unsigned int state; /* function state */ #define SDIO_STATE_PRESENT (1<<0) /* present in sysfs */ - u8 tmpbuf[4]; /* DMA:able scratch buffer */ + u8 *tmpbuf; /* DMA:able scratch buffer */ unsigned num_info; /* number of info strings */ const char **info; /* info strings */ From a6db2c86033bc41329770e90c20d4f1fec3824e4 Mon Sep 17 00:00:00 2001 From: Douglas Anderson Date: Tue, 11 Apr 2017 15:55:43 -0700 Subject: [PATCH 2/3] mmc: dw_mmc: Don't allow Runtime PM for SDIO cards According to the SDIO standard interrupts are normally signalled in a very complicated way. They require the card clock to be running and require the controller to be paying close attention to the signals coming from the card. This simply can't happen with the clock stopped or with the controller in a low power mode. To that end, we'll disable runtime_pm when we detect that an SDIO card was inserted. This is much like with what we do with the special "SDMMC_CLKEN_LOW_PWR" bit that dw_mmc supports. NOTE: we specifically do this Runtime PM disabling at card init time rather than in the enable_sdio_irq() callback. This is _different_ than how SDHCI does it. Why do we do it differently? - Unlike SDHCI, dw_mmc uses the standard sdio_irq code in Linux (AKA dw_mmc doesn't set MMC_CAP2_SDIO_IRQ_NOTHREAD). - Because we use the standard sdio_irq code: - We see a constant stream of enable_sdio_irq(0) and enable_sdio_irq(1) calls. This is because the standard code disables interrupts while processing and re-enables them after. - While interrupts are disabled, there's technically a period where we could get runtime disabled while processing interrupts. - If we are runtime disabled while processing interrupts, we'll reset the controller at resume time (see dw_mci_runtime_resume), which seems like a terrible idea because we could possibly have another interrupt pending. To fix the above isues we'd want to put something in the standard sdio_irq code that makes sure to call pm_runtime get/put when interrupts are being actively being processed. That's possible to do, but it seems like a more complicated mechanism when we really just want the runtime pm disabled always for SDIO cards given that all the other bits needed to get Runtime PM vs. SDIO just aren't there. NOTE: at some point in time someone might come up with a fancy way to do SDIO interrupts and still allow (some) amount of runtime PM. Technically we could turn off the card clock if we used an alternate way of signaling SDIO interrupts (and out of band interrupt is one way to do this). We probably wouldn't actually want to fully runtime suspend in this case though--at least not with the current dw_mci_runtime_resume() which basically fully resets the controller at resume time. Fixes: e9ed8835e990 ("mmc: dw_mmc: add runtime PM callback") Cc: Reported-by: Brian Norris Signed-off-by: Douglas Anderson Acked-by: Jaehoon Chung Reviewed-by: Shawn Lin Signed-off-by: Ulf Hansson --- drivers/mmc/host/dw_mmc.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c index a9ac0b4573131..8718432751c50 100644 --- a/drivers/mmc/host/dw_mmc.c +++ b/drivers/mmc/host/dw_mmc.c @@ -22,6 +22,7 @@ #include #include #include +#include #include #include #include @@ -1621,10 +1622,16 @@ static void dw_mci_init_card(struct mmc_host *mmc, struct mmc_card *card) if (card->type == MMC_TYPE_SDIO || card->type == MMC_TYPE_SD_COMBO) { - set_bit(DW_MMC_CARD_NO_LOW_PWR, &slot->flags); + if (!test_bit(DW_MMC_CARD_NO_LOW_PWR, &slot->flags)) { + pm_runtime_get_noresume(mmc->parent); + set_bit(DW_MMC_CARD_NO_LOW_PWR, &slot->flags); + } clk_en_a = clk_en_a_old & ~clken_low_pwr; } else { - clear_bit(DW_MMC_CARD_NO_LOW_PWR, &slot->flags); + if (test_bit(DW_MMC_CARD_NO_LOW_PWR, &slot->flags)) { + pm_runtime_put_noidle(mmc->parent); + clear_bit(DW_MMC_CARD_NO_LOW_PWR, &slot->flags); + } clk_en_a = clk_en_a_old | clken_low_pwr; } From 9f327845358d3dd0d8a5a7a5436b0aa5c432e757 Mon Sep 17 00:00:00 2001 From: Haibo Chen Date: Wed, 19 Apr 2017 10:53:51 +0800 Subject: [PATCH 3/3] mmc: sdhci-esdhc-imx: increase the pad I/O drive strength for DDR50 card Currently for DDR50 card, it need tuning in default. We meet tuning fail issue for DDR50 card and some data CRC error when DDR50 sd card works. This is because the default pad I/O drive strength can't make sure DDR50 card work stable. So increase the pad I/O drive strength for DDR50 card, and use pins_100mhz. This fixes DDR50 card support for IMX since DDR50 tuning was enabled from commit 9faac7b95ea4 ("mmc: sdhci: enable tuning for DDR50") Tested-and-reported-by: Tim Harvey Signed-off-by: Haibo Chen Cc: stable@vger.kernel.org # v4.4+ Acked-by: Dong Aisheng Acked-by: Adrian Hunter Signed-off-by: Ulf Hansson --- drivers/mmc/host/sdhci-esdhc-imx.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c b/drivers/mmc/host/sdhci-esdhc-imx.c index 7123ef96ed185..445fc47dc3e77 100644 --- a/drivers/mmc/host/sdhci-esdhc-imx.c +++ b/drivers/mmc/host/sdhci-esdhc-imx.c @@ -830,6 +830,7 @@ static int esdhc_change_pinstate(struct sdhci_host *host, switch (uhs) { case MMC_TIMING_UHS_SDR50: + case MMC_TIMING_UHS_DDR50: pinctrl = imx_data->pins_100mhz; break; case MMC_TIMING_UHS_SDR104: