@@ -562,32 +562,46 @@ static unsigned int esdhc_of_get_min_clock(struct sdhci_host *host)
static void esdhc_clock_enable(struct sdhci_host *host, bool enable)
{
- u32 val;
+ struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+ struct sdhci_esdhc *esdhc = sdhci_pltfm_priv(pltfm_host);
ktime_t timeout;
+ u32 val, clk_en;
+
+ clk_en = ESDHC_CLOCK_SDCLKEN;
+
+ /*
+ * IPGEN/HCKEN/PEREN bits exist on eSDHC whose vendor version
+ * is 2.2 or lower.
+ */
+ if (esdhc->vendor_ver <= VENDOR_V_22)
+ clk_en |= (ESDHC_CLOCK_IPGEN | ESDHC_CLOCK_HCKEN |
+ ESDHC_CLOCK_PEREN);
val = sdhci_readl(host, ESDHC_SYSTEM_CONTROL);
if (enable)
- val |= ESDHC_CLOCK_SDCLKEN;
+ val |= clk_en;
else
- val &= ~ESDHC_CLOCK_SDCLKEN;
+ val &= ~clk_en;
sdhci_writel(host, val, ESDHC_SYSTEM_CONTROL);
- /* Wait max 20 ms */
+ /*
+ * Wait max 20 ms. If vendor version is 2.2 or lower, do not
+ * wait clock stable bit which does not exist.
+ */
timeout = ktime_add_ms(ktime_get(), 20);
- val = ESDHC_CLOCK_STABLE;
- while (1) {
+ while (esdhc->vendor_ver > VENDOR_V_22) {
bool timedout = ktime_after(ktime_get(), timeout);
- if (sdhci_readl(host, ESDHC_PRSSTAT) & val)
+ if (sdhci_readl(host, ESDHC_PRSSTAT) & ESDHC_CLOCK_STABLE)
break;
if (timedout) {
pr_err("%s: Internal clock never stabilised.\n",
mmc_hostname(host->mmc));
break;
}
- udelay(10);
+ usleep_range(10, 20);
}
}
@@ -621,77 +635,97 @@ static void esdhc_of_set_clock(struct sdhci_host *host, unsigned int clock)
{
struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
struct sdhci_esdhc *esdhc = sdhci_pltfm_priv(pltfm_host);
- int pre_div = 1;
- int div = 1;
- int division;
+ unsigned int pre_div = 1, div = 1;
+ unsigned int clock_fixup = 0;
ktime_t timeout;
- long fixup = 0;
u32 temp;
- host->mmc->actual_clock = 0;
-
if (clock == 0) {
+ host->mmc->actual_clock = 0;
esdhc_clock_enable(host, false);
return;
}
- /* Workaround to start pre_div at 2 for VNN < VENDOR_V_23 */
+ /* Start pre_div at 2 for vendor version < 2.3. */
if (esdhc->vendor_ver < VENDOR_V_23)
pre_div = 2;
+ /* Fix clock value. */
if (host->mmc->card && mmc_card_sd(host->mmc->card) &&
- esdhc->clk_fixup && host->mmc->ios.timing == MMC_TIMING_LEGACY)
- fixup = esdhc->clk_fixup->sd_dflt_max_clk;
+ esdhc->clk_fixup && host->mmc->ios.timing == MMC_TIMING_LEGACY)
+ clock_fixup = esdhc->clk_fixup->sd_dflt_max_clk;
else if (esdhc->clk_fixup)
- fixup = esdhc->clk_fixup->max_clk[host->mmc->ios.timing];
-
- if (fixup && clock > fixup)
- clock = fixup;
+ clock_fixup = esdhc->clk_fixup->max_clk[host->mmc->ios.timing];
- temp = sdhci_readl(host, ESDHC_SYSTEM_CONTROL);
- temp &= ~(ESDHC_CLOCK_SDCLKEN | ESDHC_CLOCK_IPGEN | ESDHC_CLOCK_HCKEN |
- ESDHC_CLOCK_PEREN | ESDHC_CLOCK_MASK);
- sdhci_writel(host, temp, ESDHC_SYSTEM_CONTROL);
+ if (clock_fixup == 0 || clock < clock_fixup)
+ clock_fixup = clock;
- while (host->max_clk / pre_div / 16 > clock && pre_div < 256)
+ /* Calculate pre_div and div. */
+ while (host->max_clk / pre_div / 16 > clock_fixup && pre_div < 256)
pre_div *= 2;
- while (host->max_clk / pre_div / div > clock && div < 16)
+ while (host->max_clk / pre_div / div > clock_fixup && div < 16)
div++;
+ esdhc->div_ratio = pre_div * div;
+
+ /* Limit clock division for HS400 200MHz clock for quirk. */
if (esdhc->quirk_limited_clk_division &&
clock == MMC_HS200_MAX_DTR &&
(host->mmc->ios.timing == MMC_TIMING_MMC_HS400 ||
host->flags & SDHCI_HS400_TUNING)) {
- division = pre_div * div;
- if (division <= 4) {
+ if (esdhc->div_ratio <= 4) {
pre_div = 4;
div = 1;
- } else if (division <= 8) {
+ } else if (esdhc->div_ratio <= 8) {
pre_div = 4;
div = 2;
- } else if (division <= 12) {
+ } else if (esdhc->div_ratio <= 12) {
pre_div = 4;
div = 3;
} else {
pr_warn("%s: using unsupported clock division.\n",
mmc_hostname(host->mmc));
}
+ esdhc->div_ratio = pre_div * div;
}
+ host->mmc->actual_clock = host->max_clk / esdhc->div_ratio;
+
dev_dbg(mmc_dev(host->mmc), "desired SD clock: %d, actual: %d\n",
- clock, host->max_clk / pre_div / div);
- host->mmc->actual_clock = host->max_clk / pre_div / div;
- esdhc->div_ratio = pre_div * div;
+ clock, host->mmc->actual_clock);
+
+ /* Set clock division into register. */
pre_div >>= 1;
div--;
+ esdhc_clock_enable(host, false);
+
temp = sdhci_readl(host, ESDHC_SYSTEM_CONTROL);
- temp |= (ESDHC_CLOCK_IPGEN | ESDHC_CLOCK_HCKEN | ESDHC_CLOCK_PEREN
- | (div << ESDHC_DIVIDER_SHIFT)
- | (pre_div << ESDHC_PREDIV_SHIFT));
+ temp &= ~ESDHC_CLOCK_MASK;
+ temp |= ((div << ESDHC_DIVIDER_SHIFT) |
+ (pre_div << ESDHC_PREDIV_SHIFT));
sdhci_writel(host, temp, ESDHC_SYSTEM_CONTROL);
+ /*
+ * Wait max 20 ms. If vendor version is 2.2 or lower, do not
+ * wait clock stable bit which does not exist.
+ */
+ timeout = ktime_add_ms(ktime_get(), 20);
+ while (esdhc->vendor_ver > VENDOR_V_22) {
+ bool timedout = ktime_after(ktime_get(), timeout);
+
+ if (sdhci_readl(host, ESDHC_PRSSTAT) & ESDHC_CLOCK_STABLE)
+ break;
+ if (timedout) {
+ pr_err("%s: Internal clock never stabilised.\n",
+ mmc_hostname(host->mmc));
+ break;
+ }
+ usleep_range(10, 20);
+ }
+
+ /* Additional setting for HS400. */
if (host->mmc->ios.timing == MMC_TIMING_MMC_HS400 &&
clock == MMC_HS200_MAX_DTR) {
temp = sdhci_readl(host, ESDHC_TBCTL);
@@ -711,25 +745,7 @@ static void esdhc_of_set_clock(struct sdhci_host *host, unsigned int clock)
esdhc_clock_enable(host, false);
esdhc_flush_async_fifo(host);
}
-
- /* Wait max 20 ms */
- timeout = ktime_add_ms(ktime_get(), 20);
- while (1) {
- bool timedout = ktime_after(ktime_get(), timeout);
-
- if (sdhci_readl(host, ESDHC_PRSSTAT) & ESDHC_CLOCK_STABLE)
- break;
- if (timedout) {
- pr_err("%s: Internal clock never stabilised.\n",
- mmc_hostname(host->mmc));
- return;
- }
- udelay(10);
- }
-
- temp = sdhci_readl(host, ESDHC_SYSTEM_CONTROL);
- temp |= ESDHC_CLOCK_SDCLKEN;
- sdhci_writel(host, temp, ESDHC_SYSTEM_CONTROL);
+ esdhc_clock_enable(host, false);
}
static void esdhc_pltfm_set_bus_width(struct sdhci_host *host, int width)
This patch is to fix clock setting code for different controller versions. Two of HW changes after vendor version 2.2 are removing PEREN/HCKEN/IPGEN bits in system control register, and adding SD clock stable bit in present state register. This patch cleans up related code too. Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com> --- Changes for v2: - Used preferred style for comments. --- drivers/mmc/host/sdhci-of-esdhc.c | 128 +++++++++++++++++++++----------------- 1 file changed, 72 insertions(+), 56 deletions(-)