[PATCH v2 2/2] mmc: mediatek: Add HS400 online tuning support
From: Wenbin Mei
Date: Wed Sep 01 2021 - 21:52:52 EST
Due to the influence of the corner IC and vcore voltage, for the stability
of HS400 mode, we Add HS400 mode online tuning support for mediatek mmc
host.
Signed-off-by: Wenbin Mei <wenbin.mei@xxxxxxxxxxxx>
---
drivers/mmc/core/mmc.c | 8 ++++
drivers/mmc/host/mtk-sd.c | 118 +++++++++++++++++++++++++++++++++++++++++++++-
include/linux/mmc/host.h | 3 ++
3 files changed, 127 insertions(+), 2 deletions(-)
diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index 838726b..0aa72ac 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -1222,6 +1222,14 @@ 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/host/mtk-sd.c b/drivers/mmc/host/mtk-sd.c
index 4dfc246..484f5c3 100644
--- a/drivers/mmc/host/mtk-sd.c
+++ b/drivers/mmc/host/mtk-sd.c
@@ -258,6 +258,7 @@
#define MSDC_PAD_TUNE_RD_SEL (0x1 << 13) /* RW */
#define MSDC_PAD_TUNE_CMD_SEL (0x1 << 21) /* RW */
+#define PAD_DS_TUNE_DLY_SEL (0x1 << 0) /* RW */
#define PAD_DS_TUNE_DLY1 (0x1f << 2) /* RW */
#define PAD_DS_TUNE_DLY2 (0x1f << 7) /* RW */
#define PAD_DS_TUNE_DLY3 (0x1f << 12) /* RW */
@@ -301,6 +302,11 @@
#define PAD_CMD_RD_RXDLY_SEL (0x1 << 11) /* RW */
#define PAD_CMD_TX_DLY (0x1f << 12) /* RW */
+/* EMMC50_PAD_DS_TUNE mask */
+#define PAD_DS_DLY_SEL (0x1 << 16) /* RW */
+#define PAD_DS_DLY1 (0x1f << 10) /* RW */
+#define PAD_DS_DLY3 (0x1f << 0) /* RW */
+
#define REQ_CMD_EIO (0x1 << 0)
#define REQ_CMD_TMO (0x1 << 1)
#define REQ_DAT_ERR (0x1 << 2)
@@ -448,11 +454,13 @@ struct msdc_host {
bool vqmmc_enabled;
u32 latch_ck;
u32 hs400_ds_delay;
+ u32 hs400_ds_dly3;
u32 hs200_cmd_int_delay; /* cmd internal delay for HS200/SDR104 */
u32 hs400_cmd_int_delay; /* cmd internal delay for HS400 */
bool hs400_cmd_resp_sel_rising;
/* cmd response sample selection for HS400 */
bool hs400_mode; /* current eMMC will run at hs400 mode */
+ bool hs400_tuning; /* hs400 mode online tuning */
bool internal_cd; /* Use internal card-detect logic */
bool cqhci; /* support eMMC hw cmdq */
struct msdc_save_para save_para; /* used when gate HCLK */
@@ -1190,7 +1198,8 @@ static bool msdc_cmd_done(struct msdc_host *host, int events,
if (!sbc_error && !(events & MSDC_INT_CMDRDY)) {
if (events & MSDC_INT_CMDTMO ||
(cmd->opcode != MMC_SEND_TUNING_BLOCK &&
- cmd->opcode != MMC_SEND_TUNING_BLOCK_HS200))
+ cmd->opcode != MMC_SEND_TUNING_BLOCK_HS200 &&
+ !host->hs400_tuning))
/*
* should not clear fifo/interrupt as the tune data
* may have alreay come when cmd19/cmd21 gets response
@@ -1287,7 +1296,8 @@ static void msdc_cmd_next(struct msdc_host *host,
if ((cmd->error &&
!(cmd->error == -EILSEQ &&
(cmd->opcode == MMC_SEND_TUNING_BLOCK ||
- cmd->opcode == MMC_SEND_TUNING_BLOCK_HS200))) ||
+ cmd->opcode == MMC_SEND_TUNING_BLOCK_HS200 ||
+ host->hs400_tuning))) ||
(mrq->sbc && mrq->sbc->error))
msdc_request_done(host, mrq);
else if (cmd == mrq->sbc)
@@ -2251,6 +2261,106 @@ static int msdc_prepare_hs400_tuning(struct mmc_host *mmc, struct mmc_ios *ios)
return 0;
}
+static int msdc_send_cxd_data(struct mmc_card *card, struct mmc_host *host)
+{
+ struct mmc_request mrq = {};
+ struct mmc_command cmd = {};
+ struct mmc_data data = {};
+ unsigned int len = 512;
+ struct scatterlist sg;
+ u8 *ext_csd;
+
+ ext_csd = kzalloc(len, GFP_KERNEL);
+ if (!ext_csd)
+ return -ENOMEM;
+
+ mrq.cmd = &cmd;
+ mrq.data = &data;
+
+ cmd.opcode = MMC_SEND_EXT_CSD;
+ cmd.arg = 0;
+ cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_ADTC;
+
+ data.blksz = len;
+ data.blocks = 1;
+ data.flags = MMC_DATA_READ;
+ data.sg = &sg;
+ data.sg_len = 1;
+
+ sg_init_one(&sg, ext_csd, len);
+ mmc_set_data_timeout(&data, card);
+ mmc_wait_for_req(host, &mrq);
+
+ kfree(ext_csd);
+
+ if (cmd.error)
+ return cmd.error;
+ if (data.error)
+ return data.error;
+
+ return 0;
+}
+
+static int msdc_execute_hs400_tuning(struct mmc_host *mmc, struct mmc_card *card)
+{
+ struct msdc_host *host = mmc_priv(mmc);
+ struct msdc_delay_phase dly1_delay;
+ u32 val, result_dly1 = 0;
+ int i, ret;
+
+ if (host->top_base) {
+ sdr_set_bits(host->top_base + EMMC50_PAD_DS_TUNE,
+ PAD_DS_DLY_SEL);
+ if (host->hs400_ds_dly3)
+ sdr_set_field(host->top_base + EMMC50_PAD_DS_TUNE,
+ PAD_DS_DLY3, host->hs400_ds_dly3);
+ } else {
+ sdr_set_bits(host->base + PAD_DS_TUNE, PAD_DS_TUNE_DLY_SEL);
+ if (host->hs400_ds_dly3)
+ sdr_set_field(host->base + PAD_DS_TUNE,
+ PAD_DS_TUNE_DLY3, host->hs400_ds_dly3);
+ }
+
+ host->hs400_tuning = true;
+ for (i = 0; i < PAD_DELAY_MAX; i++) {
+ if (host->top_base)
+ sdr_set_field(host->top_base + EMMC50_PAD_DS_TUNE,
+ PAD_DS_DLY1, i);
+ else
+ sdr_set_field(host->base + PAD_DS_TUNE,
+ PAD_DS_TUNE_DLY1, i);
+ ret = msdc_send_cxd_data(card, mmc);
+ if (!ret)
+ result_dly1 |= (1 << i);
+ }
+ host->hs400_tuning = false;
+
+ dly1_delay = get_best_delay(host, result_dly1);
+ if (dly1_delay.maxlen == 0) {
+ dev_err(host->dev, "Failed to get DLY1 delay!\n");
+ goto fail;
+ }
+ if (host->top_base)
+ sdr_set_field(host->top_base + EMMC50_PAD_DS_TUNE,
+ PAD_DS_DLY1, dly1_delay.final_phase);
+ else
+ sdr_set_field(host->base + PAD_DS_TUNE,
+ PAD_DS_TUNE_DLY1, dly1_delay.final_phase);
+
+ if (host->top_base)
+ val = readl(host->top_base + EMMC50_PAD_DS_TUNE);
+ else
+ val = readl(host->base + PAD_DS_TUNE);
+
+ dev_info(host->dev, "Fianl PAD_DS_TUNE: 0x%x\n", val);
+
+ return 0;
+
+fail:
+ dev_err(host->dev, "Failed to tuning DS pin delay!\n");
+ return -EIO;
+}
+
static void msdc_hw_reset(struct mmc_host *mmc)
{
struct msdc_host *host = mmc_priv(mmc);
@@ -2377,6 +2487,7 @@ static void msdc_cqe_post_disable(struct mmc_host *mmc)
.card_busy = msdc_card_busy,
.execute_tuning = msdc_execute_tuning,
.prepare_hs400_tuning = msdc_prepare_hs400_tuning,
+ .execute_hs400_tuning = msdc_execute_hs400_tuning,
.hw_reset = msdc_hw_reset,
};
@@ -2396,6 +2507,9 @@ static void msdc_of_property_parse(struct platform_device *pdev,
of_property_read_u32(pdev->dev.of_node, "hs400-ds-delay",
&host->hs400_ds_delay);
+ of_property_read_u32(pdev->dev.of_node, "mediatek,hs400-ds-dly3",
+ &host->hs400_ds_dly3);
+
of_property_read_u32(pdev->dev.of_node, "mediatek,hs200-cmd-int-delay",
&host->hs200_cmd_int_delay);
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index ff1a251..7552d5e 100644
--- 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);
--
1.9.1