mmc: loongson2: Add Loongson-2K0300 SD/SDIO/eMMC controller driver

This patch describes the two MMC controllers of the Loongson-2K0300 SoC,
one providing an eMMC interface and the other exporting an SD/SDIO
interface.

Its hardware design is similar to that of the Loongson-2K2000, but it
suffers from hardware defects such as missing CMD48 interrupts.

Signed-off-by: Binbin Zhou <zhoubinbin@loongson.cn>
Reviewed-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

diff --git a/drivers/mmc/host/loongson2-mmc.c b/drivers/mmc/host/loongson2-mmc.c
index 333bed60df3bdbc37e145847c3f2c15fb2796aba..f553e92fd9e541cab512eb7b5da2f2ea585defac 100644 (file)
--- a/drivers/mmc/host/loongson2-mmc.c
+++ b/drivers/mmc/host/loongson2-mmc.c
@@ -189,6 +189,12 @@
 #define LOONGSON2_MMC_DLLVAL_TIMEOUT_US                4000
 #define LOONGSON2_MMC_TXFULL_TIMEOUT_US                500
 
+/*
+ * Due to a hardware design flaw, the Loongson-2K0300 may fail to recognize the
+ * CMD48 (SD_READ_EXTR_SINGLE) interrupt.
+ */
+#define LOONGSON2_MMC_CMD48_QUIRK      BIT(0)
+
 /* Loongson-2K1000 SDIO2 DMA routing register */
 #define LS2K1000_SDIO_DMA_MASK         GENMASK(17, 15)
 #define LS2K1000_DMA0_CONF             0x0
@@ -245,6 +251,7 @@ struct loongson2_mmc_host {
 };
 
 struct loongson2_mmc_pdata {
+       u32 flags;
        const struct regmap_config *regmap_config;
        void (*reorder_cmd_data)(struct loongson2_mmc_host *host, struct mmc_command *cmd);
        void (*fix_data_timeout)(struct loongson2_mmc_host *host, struct mmc_command *cmd);
@@ -568,6 +575,12 @@ static void loongson2_mmc_request(struct mmc_host *mmc, struct mmc_request *mrq)
 {
        struct loongson2_mmc_host *host = mmc_priv(mmc);
 
+       if ((host->pdata->flags & LOONGSON2_MMC_CMD48_QUIRK) &&
+           mrq->cmd->opcode == SD_READ_EXTR_SINGLE) {
+               mmc_request_done(mmc, mrq);
+               return;
+       }
+
        host->cmd_is_stop = 0;
        host->mrq = mrq;
        loongson2_mmc_send_request(mmc);
@@ -839,7 +852,18 @@ static void loongson2_mmc_release_internal_dma(struct loongson2_mmc_host *host,
        dma_free_coherent(dev, PAGE_SIZE, host->sg_cpu, host->sg_dma);
 }
 
+static struct loongson2_mmc_pdata ls2k0300_mmc_pdata = {
+       .flags                  = LOONGSON2_MMC_CMD48_QUIRK,
+       .regmap_config          = &ls2k2000_mmc_regmap_config,
+       .reorder_cmd_data       = ls2k2000_mmc_reorder_cmd_data,
+       .fix_data_timeout       = ls2k2000_mmc_fix_data_timeout,
+       .setting_dma            = ls2k2000_mmc_set_internal_dma,
+       .prepare_dma            = loongson2_mmc_prepare_internal_dma,
+       .release_dma            = loongson2_mmc_release_internal_dma,
+};
+
 static struct loongson2_mmc_pdata ls2k0500_mmc_pdata = {
+       .flags                  = 0,
        .regmap_config          = &ls2k0500_mmc_regmap_config,
        .reorder_cmd_data       = ls2k0500_mmc_reorder_cmd_data,
        .setting_dma            = ls2k0500_mmc_set_external_dma,
@@ -848,6 +872,7 @@ static struct loongson2_mmc_pdata ls2k0500_mmc_pdata = {
 };
 
 static struct loongson2_mmc_pdata ls2k1000_mmc_pdata = {
+       .flags                  = 0,
        .regmap_config          = &ls2k0500_mmc_regmap_config,
        .reorder_cmd_data       = ls2k0500_mmc_reorder_cmd_data,
        .setting_dma            = ls2k1000_mmc_set_external_dma,
@@ -856,6 +881,7 @@ static struct loongson2_mmc_pdata ls2k1000_mmc_pdata = {
 };
 
 static struct loongson2_mmc_pdata ls2k2000_mmc_pdata = {
+       .flags                  = 0,
        .regmap_config          = &ls2k2000_mmc_regmap_config,
        .reorder_cmd_data       = ls2k2000_mmc_reorder_cmd_data,
        .fix_data_timeout       = ls2k2000_mmc_fix_data_timeout,
@@ -984,6 +1010,7 @@ static void loongson2_mmc_remove(struct platform_device *pdev)
 }
 
 static const struct of_device_id loongson2_mmc_of_ids[] = {
+       { .compatible = "loongson,ls2k0300-mmc", .data = &ls2k0300_mmc_pdata },
        { .compatible = "loongson,ls2k0500-mmc", .data = &ls2k0500_mmc_pdata },
        { .compatible = "loongson,ls2k1000-mmc", .data = &ls2k1000_mmc_pdata },
        { .compatible = "loongson,ls2k2000-mmc", .data = &ls2k2000_mmc_pdata },