[PATCH 1/4] mmc: mediatek: Add online-tuning support of EMMC/SD

Chaotian Jing
2015-08-12T08:24:02Z

Schedule a workqueue to do tuning when CRC error
Call mmc_hw_reset to re-init card when data timeout

Signed-off-by: Chaotian Jing <chaotian.jing-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org>
---
drivers/mmc/host/mtk-sd.c | 162 ++++++++++++++++++++++++++++++++++++++++++----
1 file changed, 150 insertions(+), 12 deletions(-)

diff --git a/drivers/mmc/host/mtk-sd.c b/drivers/mmc/host/mtk-sd.c
index 7153500..eb44fe1 100644
--- a/drivers/mmc/host/mtk-sd.c
+++ b/drivers/mmc/host/mtk-sd.c
@@ -27,6 +27,7 @@
#include <linux/pm_runtime.h>
#include <linux/regulator/consumer.h>
#include <linux/spinlock.h>
+#include <linux/workqueue.h>

#include <linux/mmc/card.h>
#include <linux/mmc/core.h>
@@ -290,6 +291,10 @@ struct msdc_host {
struct pinctrl_state *pins_default;
struct pinctrl_state *pins_uhs;
struct delayed_work req_timeout;
+ struct workqueue_struct *repeat_workqueue;
+ struct work_struct repeat_req;
+ struct mmc_request *repeat_mrq;
+ u32 tune_cmd_counter;
int irq; /* host interrupt */

struct clk *src_clk; /* msdc source clock */
@@ -353,7 +358,10 @@ static void msdc_reset_hw(struct msdc_host *host)
static void msdc_cmd_next(struct msdc_host *host,
struct mmc_request *mrq, struct mmc_command *cmd);

-static u32 data_ints_mask = MSDC_INTEN_XFER_COMPL | MSDC_INTEN_DATTMO |
+static const u32 cmd_ints_mask = MSDC_INTEN_CMDRDY | MSDC_INTEN_RSPCRCERR |
+ MSDC_INTEN_CMDTMO | MSDC_INTEN_ACMDRDY |
+ MSDC_INTEN_ACMDCRCERR | MSDC_INTEN_ACMDTMO;
+static const u32 data_ints_mask = MSDC_INTEN_XFER_COMPL | MSDC_INTEN_DATTMO |
MSDC_INTEN_DATCRCERR | MSDC_INTEN_DMA_BDCSERR |
MSDC_INTEN_DMA_GPDCSERR | MSDC_INTEN_DMA_PROTECT;

@@ -690,6 +698,18 @@ static void msdc_request_done(struct msdc_host *host, struct mmc_request *mrq)
msdc_track_cmd_data(host, mrq->cmd, mrq->data);
if (mrq->data)
msdc_unprepare_data(host, mrq);
+ if (host->error && host->mmc->card &&
+ !mmc_card_sdio(host->mmc->card)) {
+ if (mrq->cmd->error == (unsigned int)-EILSEQ ||
+ (mrq->stop && mrq->stop->error == (unsigned int)-EILSEQ) ||
+ (mrq->sbc && mrq->sbc->error == (unsigned int)-EILSEQ) ||
+ (mrq->data && mrq->data->error)) {
+ host->repeat_mrq = mrq;
+ queue_work(host->repeat_workqueue, &host->repeat_req);
+ return;
+ }
+ }
+ host->tune_cmd_counter = 0;
mmc_request_done(host->mmc, mrq);

pm_runtime_mark_last_busy(host->dev);
@@ -725,11 +745,7 @@ static bool msdc_cmd_done(struct msdc_host *host, int events,
if (done)
return true;

- sdr_clr_bits(host->base + MSDC_INTEN, MSDC_INTEN_CMDRDY |
- MSDC_INTEN_RSPCRCERR | MSDC_INTEN_CMDTMO |
- MSDC_INTEN_ACMDRDY | MSDC_INTEN_ACMDCRCERR |
- MSDC_INTEN_ACMDTMO);
- writel(cmd->arg, host->base + SDC_ARG);
+ sdr_clr_bits(host->base + MSDC_INTEN, cmd_ints_mask);

if (cmd->flags & MMC_RSP_PRESENT) {
if (cmd->flags & MMC_RSP_136) {
@@ -819,10 +835,7 @@ static void msdc_start_command(struct msdc_host *host,
rawcmd = msdc_cmd_prepare_raw_cmd(host, mrq, cmd);
mod_delayed_work(system_wq, &host->req_timeout, DAT_TIMEOUT);

- sdr_set_bits(host->base + MSDC_INTEN, MSDC_INTEN_CMDRDY |
- MSDC_INTEN_RSPCRCERR | MSDC_INTEN_CMDTMO |
- MSDC_INTEN_ACMDRDY | MSDC_INTEN_ACMDCRCERR |
- MSDC_INTEN_ACMDTMO);
+ sdr_set_bits(host->base + MSDC_INTEN, cmd_ints_mask);
writel(cmd->arg, host->base + SDC_ARG);
writel(rawcmd, host->base + SDC_CMD);
}
@@ -942,6 +955,8 @@ static bool msdc_data_xfer_done(struct msdc_host *host, u32 events,

if (events & MSDC_INT_DATTMO)
data->error = -ETIMEDOUT;
+ else if (events & MSDC_INT_DATCRCERR)
+ data->error = -EILSEQ;

dev_err(host->dev, "%s: cmd=%d; blocks=%d",
__func__, mrq->cmd->opcode, data->blocks);
@@ -1113,8 +1128,8 @@ static void msdc_init_hw(struct msdc_host *host)

writel(0, host->base + MSDC_PAD_TUNE);
writel(0, host->base + MSDC_IOCON);
- sdr_set_field(host->base + MSDC_IOCON, MSDC_IOCON_DDLSEL, 1);
- writel(0x403c004f, host->base + MSDC_PATCH_BIT);
+ sdr_set_field(host->base + MSDC_IOCON, MSDC_IOCON_DDLSEL, 0);
+ writel(0x403c0046, host->base + MSDC_PATCH_BIT);
sdr_set_field(host->base + MSDC_PATCH_BIT, MSDC_CKGEN_MSDC_DLY_SEL, 1);
writel(0xffff0089, host->base + MSDC_PATCH_BIT1);
/* Configure to enable SDIO mode.
@@ -1176,6 +1191,7 @@ static void msdc_ops_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
switch (ios->power_mode) {
case MMC_POWER_UP:
if (!IS_ERR(mmc->supply.vmmc)) {
+ msdc_init_hw(host);
ret = mmc_regulator_set_ocr(mmc, mmc->supply.vmmc,
ios->vdd);
if (ret) {
@@ -1214,6 +1230,120 @@ end:
pm_runtime_put_autosuspend(host->dev);
}

+static void msdc_reset_mrq(struct mmc_request *mrq)
+{
+ mrq->cmd->error = 0;
+ if (mrq->sbc)
+ mrq->sbc->error = 0;
+ if (mrq->data)
+ mrq->data->error = 0;
+ if (mrq->stop)
+ mrq->stop->error = 0;
+}
+
+/* Send CMD12 when tuning, do not check CRC error and timeout */
+static void msdc_send_stop(struct msdc_host *host)
+{
+ u32 opcode = MMC_STOP_TRANSMISSION;
+ u32 arg = 0;
+ u32 rawcmd = 0;
+ u32 intsts = 0;
+
+ /* Reset host first */
+ msdc_reset_hw(host);
+
+ rawcmd = (opcode & 0x3f) | (7 << 7);
+ rawcmd |= (1 << 14); /* stop cmd */
+
+ sdr_clr_bits(host->base + MSDC_INTEN, cmd_ints_mask);
+ writel(arg, host->base + SDC_ARG);
+ writel(rawcmd, host->base + SDC_CMD);
+
+ while (1) {
+ intsts = readl(host->base + MSDC_INT);
+ if (intsts) {
+ writel(intsts, host->base + MSDC_INT);
+ if (intsts & cmd_ints_mask) {
+ dev_dbg(host->dev, "result of cmd12: %x\n",
+ intsts);
+ break;
+ }
+ }
+ udelay(1);
+ }
+}
+
+/* When tuning, CMD13 may also get crc error, so use MSDC_PS to get card status */
+static void msdc_wait_card_not_busy(struct msdc_host *host)
+{
+ while (1) {
+ if ((readl(host->base + MSDC_PS) & BIT(16)) == 0) { /* check dat0 status */
+ msleep_interruptible(10);
+ dev_dbg(host->dev, "MSDC_PS: %08x, SDC_STS: %08x\n",
+ readl(host->base + MSDC_PS), readl(host->base + SDC_STS));
+ } else
+ break;
+ }
+}
+
+static void msdc_tune_request(struct msdc_host *host)
+{
+ u32 orig_rsmpl, orig_cksel;
+ u32 cur_rsmpl, cur_cksel = 0;
+ u32 ddr, clkmode;
+ struct mmc_ios ios = host->mmc->ios;
+
+ sdr_get_field(host->base + MSDC_IOCON, MSDC_IOCON_RSPL, &orig_rsmpl);
+ sdr_get_field(host->base + MSDC_PATCH_BIT, MSDC_CKGEN_MSDC_DLY_SEL,
+ &orig_cksel);
+ cur_rsmpl = (orig_rsmpl + 1);
+ sdr_set_field(host->base + MSDC_IOCON, MSDC_IOCON_RSPL, cur_rsmpl % 2);
+
+ if (ios.timing != MMC_TIMING_MMC_HS400) {
+ sdr_set_field(host->base + MSDC_IOCON, MSDC_IOCON_DSPL,
+ cur_rsmpl % 2);
+ sdr_set_field(host->base + MSDC_IOCON, MSDC_IOCON_W_DSPL,
+ cur_rsmpl % 2);
+ }
+
+ if (cur_rsmpl >= 2) {
+ cur_cksel = orig_cksel + 1;
+ sdr_set_field(host->base + MSDC_PATCH_BIT,
+ MSDC_CKGEN_MSDC_DLY_SEL, cur_cksel % 16);
+ }
+
+ if (host->tune_cmd_counter++ >= 2 * 16) {
+ dev_warn(host->dev, "Tune fail at %dhz\n", host->mclk);
+ host->tune_cmd_counter = 0;
+ sdr_set_field(host->base + MSDC_IOCON, MSDC_IOCON_RSPL, 0);
+ sdr_set_field(host->base + MSDC_PATCH_BIT,
+ MSDC_CKGEN_MSDC_DLY_SEL, 0);
+ sdr_get_field(host->base + MSDC_CFG, MSDC_CFG_CKMOD, &clkmode);
+ ddr = (clkmode == 2) ? 1 : 0;
+ msdc_set_mclk(host, ddr, host->mclk / 2);
+ }
+}
+
+static void msdc_repeat_request(struct work_struct *work)
+{
+ struct msdc_host *host = container_of(work, struct msdc_host, repeat_req);
+ struct mmc_request *mrq;
+ unsigned long flags;
+
+ spin_lock_irqsave(&host->lock, flags);
+ mrq = host->repeat_mrq;
+ host->repeat_mrq = NULL;
+ spin_unlock_irqrestore(&host->lock, flags);
+ msdc_send_stop(host);
+ msdc_wait_card_not_busy(host);
+ if (mrq->data && mrq->data->error == -ETIMEDOUT)
+ mmc_hw_reset(host->mmc);
+ else
+ msdc_tune_request(host);
+ msdc_reset_mrq(mrq);
+ msdc_ops_request(host->mmc, mrq);
+}
+
static struct mmc_host_ops mt_msdc_ops = {
.post_req = msdc_post_req,
.pre_req = msdc_pre_req,
@@ -1324,6 +1454,12 @@ static int msdc_drv_probe(struct platform_device *pdev)
}
msdc_init_gpd_bd(host, &host->dma);
INIT_DELAYED_WORK(&host->req_timeout, msdc_request_timeout);
+ host->repeat_workqueue = create_singlethread_workqueue("repeat_workqueue");
+ if (!host->repeat_workqueue) {
+ ret = -ENOMEM;
+ goto release_mem;
+ }
+ INIT_WORK(&host->repeat_req, msdc_repeat_request);
spin_lock_init(&host->lock);

platform_set_drvdata(pdev, mmc);
@@ -1348,6 +1484,7 @@ static int msdc_drv_probe(struct platform_device *pdev)
end:
pm_runtime_disable(host->dev);
release:
+ destroy_workqueue(host->repeat_workqueue);
platform_set_drvdata(pdev, NULL);
msdc_deinit_hw(host);
msdc_gate_clock(host);
@@ -1383,6 +1520,7 @@ static int msdc_drv_remove(struct platform_device *pdev)

pm_runtime_disable(host->dev);
pm_runtime_put_noidle(host->dev);
+ destroy_workqueue(host->repeat_workqueue);
dma_free_coherent(&pdev->dev,
sizeof(struct mt_gpdma_desc),
host->dma.gpd, host->dma.gpd_addr);
--
1.8.1.1.dirty