[PATCH v2 8/9] mmc: meson-gx: improve initial configuration

Heiner Kallweit
2017-02-16T19:43:13Z

Config values which are not changed during runtime we can set
in the probe function already.
The block size setting is overwritten later in
meson_mmc_start_cmd anyway if needed, so it doesn't harm if we
remove this setting in meson_mmc_set_ios.

In addition:
- write config register only if configuration changed
- Initialize clocks after other config registers have been initialized

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Acked-by: Kevin Hilman <khilman@baylibre.com>
---
v2:
- added acked-by
---
drivers/mmc/host/meson-gx-mmc.c | 37 +++++++++++++++++++++----------------
1 file changed, 21 insertions(+), 16 deletions(-)

diff --git a/drivers/mmc/host/meson-gx-mmc.c b/drivers/mmc/host/meson-gx-mmc.c
index a8f43cc6..e7c3ac1c 100644
--- a/drivers/mmc/host/meson-gx-mmc.c
+++ b/drivers/mmc/host/meson-gx-mmc.c
@@ -390,15 +390,6 @@ static void meson_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
val &= ~(CFG_BUS_WIDTH_MASK << CFG_BUS_WIDTH_SHIFT);
val |= bus_width << CFG_BUS_WIDTH_SHIFT;

- val &= ~(CFG_BLK_LEN_MASK << CFG_BLK_LEN_SHIFT);
- val |= ilog2(SD_EMMC_CFG_BLK_SIZE) << CFG_BLK_LEN_SHIFT;
-
- val &= ~(CFG_RESP_TIMEOUT_MASK << CFG_RESP_TIMEOUT_SHIFT);
- val |= ilog2(SD_EMMC_CFG_RESP_TIMEOUT) << CFG_RESP_TIMEOUT_SHIFT;
-
- val &= ~(CFG_RC_CC_MASK << CFG_RC_CC_SHIFT);
- val |= ilog2(SD_EMMC_CFG_CMD_GAP) << CFG_RC_CC_SHIFT;
-
val &= ~CFG_DDR;
if (ios->timing == MMC_TIMING_UHS_DDR50 ||
ios->timing == MMC_TIMING_MMC_DDR52 ||
@@ -409,11 +400,11 @@ static void meson_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
if (ios->timing == MMC_TIMING_MMC_HS400)
val |= CFG_CHK_DS;

- writel(val, host->regs + SD_EMMC_CFG);
-
- if (val != orig)
+ if (val != orig) {
+ writel(val, host->regs + SD_EMMC_CFG);
dev_dbg(host->dev, "%s: SD_EMMC_CFG: 0x%08x -> 0x%08x\n",
__func__, orig, val);
+ }
}

static void meson_mmc_request_done(struct mmc_host *mmc,
@@ -691,6 +682,17 @@ static int meson_mmc_get_cd(struct mmc_host *mmc)
return status;
}

+static void meson_mmc_cfg_init(struct meson_host *host)
+{
+ u32 cfg = 0;
+
+ cfg |= ilog2(SD_EMMC_CFG_RESP_TIMEOUT) << CFG_RESP_TIMEOUT_SHIFT;
+ cfg |= ilog2(SD_EMMC_CFG_CMD_GAP) << CFG_RC_CC_SHIFT;
+ cfg |= ilog2(SD_EMMC_CFG_BLK_SIZE) << CFG_BLK_LEN_SHIFT;
+
+ writel(cfg, host->regs + SD_EMMC_CFG);
+}
+
static const struct mmc_host_ops meson_mmc_ops = {
.request = meson_mmc_request,
.set_ios = meson_mmc_set_ios,
@@ -751,10 +753,6 @@ static int meson_mmc_probe(struct platform_device *pdev)
if (ret)
goto free_host;

- ret = meson_mmc_clk_init(host);
- if (ret)
- goto free_host;
-
/* Stop execution */
writel(0, host->regs + SD_EMMC_START);

@@ -763,6 +761,13 @@ static int meson_mmc_probe(struct platform_device *pdev)
writel(IRQ_EN_MASK, host->regs + SD_EMMC_STATUS);
writel(IRQ_EN_MASK, host->regs + SD_EMMC_IRQ_EN);

+ /* set config to sane default */
+ meson_mmc_cfg_init(host);
+
+ ret = meson_mmc_clk_init(host);
+ if (ret)
+ goto free_host;
+
ret = devm_request_threaded_irq(&pdev->dev, irq, meson_mmc_irq,
meson_mmc_irq_thread, IRQF_SHARED,
DRIVER_NAME, host);
--
2.11.1