mmc: core: Add host specific tuning support for eMMC HS400 mode

This adds a ->execute_hs400_tuning() host callback to enable optional
support for host specific tuning for eMMC HS400 mode. Additionally, share
mmc_get_ext_csd() through the public host headerfile, to allow it to be
used by the host drivers, which is needed to support the HS400 tuning.

Signed-off-by: Wenbin Mei <wenbin.mei@mediatek.com>
Link: https://lore.kernel.org/r/20210917124803.22871-3-wenbin.mei@mediatek.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index 29e58ff..b1c1716 100644 (file)
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -1224,6 +1224,14 @@ static int mmc_select_hs400(struct mmc_card *card)
        mmc_set_timing(host, MMC_TIMING_MMC_HS400);
        mmc_set_bus_speed(card);
 
+       if (host->ops->execute_hs400_tuning) {
+               mmc_retune_disable(host);
+               err = host->ops->execute_hs400_tuning(host, card);
+               mmc_retune_enable(host);
+               if (err)
+                       goto out_err;
+       }
+
        if (host->ops->hs400_complete)
                host->ops->hs400_complete(host);
 

diff --git a/drivers/mmc/core/mmc_ops.h b/drivers/mmc/core/mmc_ops.h
index ae25ffc..e5e9456 100644 (file)
--- a/drivers/mmc/core/mmc_ops.h
+++ b/drivers/mmc/core/mmc_ops.h
@@ -38,7 +38,6 @@ int mmc_spi_read_ocr(struct mmc_host *host, int highcap, u32 *ocrp);
 int mmc_spi_set_crc(struct mmc_host *host, int use_crc);
 int mmc_bus_test(struct mmc_card *card, u8 bus_width);
 int mmc_can_ext_csd(struct mmc_card *card);
-int mmc_get_ext_csd(struct mmc_card *card, u8 **new_ext_csd);
 int mmc_switch_status(struct mmc_card *card, bool crc_err_fatal);
 bool mmc_prepare_busy_cmd(struct mmc_host *host, struct mmc_command *cmd,
                          unsigned int timeout_ms);

diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index 0c0c9a0..b6c082e 100644 (file)
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -162,6 +162,9 @@ struct mmc_host_ops {
        /* Prepare HS400 target operating frequency depending host driver */
        int     (*prepare_hs400_tuning)(struct mmc_host *host, struct mmc_ios *ios);
 
+       /* Execute HS400 tuning depending host driver */
+       int     (*execute_hs400_tuning)(struct mmc_host *host, struct mmc_card *card);
+
        /* Prepare switch to DDR during the HS400 init sequence */
        int     (*hs400_prepare_ddr)(struct mmc_host *host);
 
@@ -634,5 +637,6 @@ static inline enum dma_data_direction mmc_get_dma_dir(struct mmc_data *data)
 
 int mmc_send_tuning(struct mmc_host *host, u32 opcode, int *cmd_error);
 int mmc_send_abort_tuning(struct mmc_host *host, u32 opcode);
+int mmc_get_ext_csd(struct mmc_card *card, u8 **new_ext_csd);
 
 #endif /* LINUX_MMC_HOST_H */