From 24552ccb4f1e0a9bf961056057aa8bd4c0d8dfe8 Mon Sep 17 00:00:00 2001 From: Doug Brown Date: Mon, 16 Jan 2023 11:43:59 -0800 Subject: [PATCH] mmc: sdhci-pxav2: add SDIO card IRQ workaround for PXA168 V1 controller The PXA168 has a documented silicon bug that causes SDIO card IRQs to be missed. Implement the first half of the suggested workaround, which involves resetting the data port logic and issuing a dummy CMD0 to restart the clock. Signed-off-by: Doug Brown Acked-by: Adrian Hunter Link: https://lore.kernel.org/r/20230116194401.20372-7-doug@schmorgal.com Signed-off-by: Ulf Hansson --- drivers/mmc/host/sdhci-pxav2.c | 56 +++++++++++++++++++++++++++++++++++++++++- 1 file changed, 55 insertions(+), 1 deletion(-) diff --git a/drivers/mmc/host/sdhci-pxav2.c b/drivers/mmc/host/sdhci-pxav2.c index 3141901..3dafffa 100644 --- a/drivers/mmc/host/sdhci-pxav2.c +++ b/drivers/mmc/host/sdhci-pxav2.c @@ -20,6 +20,8 @@ #include #include #include +#include +#include #include "sdhci.h" #include "sdhci-pltfm.h" @@ -41,6 +43,10 @@ #define MMC_CARD 0x1000 #define MMC_WIDTH 0x0100 +struct sdhci_pxav2_host { + struct mmc_request *sdio_mrq; +}; + static void pxav2_reset(struct sdhci_host *host, u8 mask) { struct platform_device *pdev = to_platform_device(mmc_dev(host->mmc)); @@ -89,6 +95,52 @@ static u16 pxav1_readw(struct sdhci_host *host, int reg) return readw(host->ioaddr + reg); } +static u32 pxav1_irq(struct sdhci_host *host, u32 intmask) +{ + struct sdhci_pxav2_host *pxav2_host = sdhci_pltfm_priv(sdhci_priv(host)); + struct mmc_request *sdio_mrq; + + if (pxav2_host->sdio_mrq && (intmask & SDHCI_INT_CMD_MASK)) { + /* The dummy CMD0 for the SDIO workaround just completed */ + sdhci_writel(host, intmask & SDHCI_INT_CMD_MASK, SDHCI_INT_STATUS); + intmask &= ~SDHCI_INT_CMD_MASK; + sdio_mrq = pxav2_host->sdio_mrq; + pxav2_host->sdio_mrq = NULL; + mmc_request_done(host->mmc, sdio_mrq); + } + + return intmask; +} + +static void pxav1_request_done(struct sdhci_host *host, struct mmc_request *mrq) +{ + u16 tmp; + struct sdhci_pxav2_host *pxav2_host; + + /* If this is an SDIO command, perform errata workaround for silicon bug */ + if (mrq->cmd && !mrq->cmd->error && + (mrq->cmd->opcode == SD_IO_RW_DIRECT || + mrq->cmd->opcode == SD_IO_RW_EXTENDED)) { + /* Reset data port */ + tmp = readw(host->ioaddr + SDHCI_TIMEOUT_CONTROL); + tmp |= 0x400; + writew(tmp, host->ioaddr + SDHCI_TIMEOUT_CONTROL); + + /* Clock is now stopped, so restart it by sending a dummy CMD0 */ + pxav2_host = sdhci_pltfm_priv(sdhci_priv(host)); + pxav2_host->sdio_mrq = mrq; + sdhci_writel(host, 0, SDHCI_ARGUMENT); + sdhci_writew(host, 0, SDHCI_TRANSFER_MODE); + sdhci_writew(host, SDHCI_MAKE_CMD(MMC_GO_IDLE_STATE, SDHCI_CMD_RESP_NONE), + SDHCI_COMMAND); + + /* Don't finish this request until the dummy CMD0 finishes */ + return; + } + + mmc_request_done(host->mmc, mrq); +} + static void pxav2_mmc_set_bus_width(struct sdhci_host *host, int width) { u8 ctrl; @@ -118,10 +170,12 @@ struct sdhci_pxa_variant { static const struct sdhci_ops pxav1_sdhci_ops = { .read_w = pxav1_readw, .set_clock = sdhci_set_clock, + .irq = pxav1_irq, .get_max_clock = sdhci_pltfm_clk_get_max_clock, .set_bus_width = pxav2_mmc_set_bus_width, .reset = pxav2_reset, .set_uhs_signaling = sdhci_set_uhs_signaling, + .request_done = pxav1_request_done, }; static const struct sdhci_pxa_variant __maybe_unused pxav1_variant = { @@ -193,7 +247,7 @@ static int sdhci_pxav2_probe(struct platform_device *pdev) int ret; struct clk *clk, *clk_core; - host = sdhci_pltfm_init(pdev, NULL, 0); + host = sdhci_pltfm_init(pdev, NULL, sizeof(struct sdhci_pxav2_host)); if (IS_ERR(host)) return PTR_ERR(host); -- 2.7.4