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path: root/drivers/mmc/host/sdhci-of-arasan.c
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Diffstat (limited to 'drivers/mmc/host/sdhci-of-arasan.c')
-rw-r--r--drivers/mmc/host/sdhci-of-arasan.c136
1 files changed, 120 insertions, 16 deletions
diff --git a/drivers/mmc/host/sdhci-of-arasan.c b/drivers/mmc/host/sdhci-of-arasan.c
index e0f193f7e3e5..da8e40af6f85 100644
--- a/drivers/mmc/host/sdhci-of-arasan.c
+++ b/drivers/mmc/host/sdhci-of-arasan.c
@@ -26,6 +26,7 @@
#include <linux/phy/phy.h>
#include <linux/regmap.h>
#include "sdhci-pltfm.h"
+#include <linux/of.h>
#define SDHCI_ARASAN_CLK_CTRL_OFFSET 0x2c
#define SDHCI_ARASAN_VENDOR_REGISTER 0x78
@@ -35,6 +36,8 @@
#define CLK_CTRL_TIMEOUT_MASK (0xf << CLK_CTRL_TIMEOUT_SHIFT)
#define CLK_CTRL_TIMEOUT_MIN_EXP 13
+#define PHY_CLK_TOO_SLOW_HZ 400000
+
/*
* On some SoCs the syscon area has a feature where the upper 16-bits of
* each 32-bit register act as a write mask for the lower 16-bits. This allows
@@ -65,10 +68,12 @@ struct sdhci_arasan_soc_ctl_field {
* accessible via the syscon API.
*
* @baseclkfreq: Where to find corecfg_baseclkfreq
+ * @clockmultiplier: Where to find corecfg_clockmultiplier
* @hiword_update: If true, use HIWORD_UPDATE to access the syscon
*/
struct sdhci_arasan_soc_ctl_map {
struct sdhci_arasan_soc_ctl_field baseclkfreq;
+ struct sdhci_arasan_soc_ctl_field clockmultiplier;
bool hiword_update;
};
@@ -77,6 +82,7 @@ struct sdhci_arasan_soc_ctl_map {
* @host: Pointer to the main SDHCI host structure.
* @clk_ahb: Pointer to the AHB clock
* @phy: Pointer to the generic phy
+ * @is_phy_on: True if the PHY is on; false if not.
* @sdcardclk_hw: Struct for the clock we might provide to a PHY.
* @sdcardclk: Pointer to normal 'struct clock' for sdcardclk_hw.
* @soc_ctl_base: Pointer to regmap for syscon for soc_ctl registers.
@@ -86,16 +92,22 @@ struct sdhci_arasan_data {
struct sdhci_host *host;
struct clk *clk_ahb;
struct phy *phy;
+ bool is_phy_on;
struct clk_hw sdcardclk_hw;
struct clk *sdcardclk;
struct regmap *soc_ctl_base;
const struct sdhci_arasan_soc_ctl_map *soc_ctl_map;
+ unsigned int quirks; /* Arasan deviations from spec */
+
+/* Controller does not have CD wired and will not function normally without */
+#define SDHCI_ARASAN_QUIRK_FORCE_CDTEST BIT(0)
};
static const struct sdhci_arasan_soc_ctl_map rk3399_soc_ctl_map = {
.baseclkfreq = { .reg = 0xf000, .width = 8, .shift = 8 },
+ .clockmultiplier = { .reg = 0xf02c, .width = 8, .shift = 0},
.hiword_update = true,
};
@@ -170,13 +182,47 @@ static void sdhci_arasan_set_clock(struct sdhci_host *host, unsigned int clock)
struct sdhci_arasan_data *sdhci_arasan = sdhci_pltfm_priv(pltfm_host);
bool ctrl_phy = false;
- if (clock > MMC_HIGH_52_MAX_DTR && (!IS_ERR(sdhci_arasan->phy)))
- ctrl_phy = true;
+ if (!IS_ERR(sdhci_arasan->phy)) {
+ if (!sdhci_arasan->is_phy_on && clock <= PHY_CLK_TOO_SLOW_HZ) {
+ /*
+ * If PHY off, set clock to max speed and power PHY on.
+ *
+ * Although PHY docs apparently suggest power cycling
+ * when changing the clock the PHY doesn't like to be
+ * powered on while at low speeds like those used in ID
+ * mode. Even worse is powering the PHY on while the
+ * clock is off.
+ *
+ * To workaround the PHY limitations, the best we can
+ * do is to power it on at a faster speed and then slam
+ * through low speeds without power cycling.
+ */
+ sdhci_set_clock(host, host->max_clk);
+ spin_unlock_irq(&host->lock);
+ phy_power_on(sdhci_arasan->phy);
+ spin_lock_irq(&host->lock);
+ sdhci_arasan->is_phy_on = true;
+
+ /*
+ * We'll now fall through to the below case with
+ * ctrl_phy = false (so we won't turn off/on). The
+ * sdhci_set_clock() will set the real clock.
+ */
+ } else if (clock > PHY_CLK_TOO_SLOW_HZ) {
+ /*
+ * At higher clock speeds the PHY is fine being power
+ * cycled and docs say you _should_ power cycle when
+ * changing clock speeds.
+ */
+ ctrl_phy = true;
+ }
+ }
- if (ctrl_phy) {
+ if (ctrl_phy && sdhci_arasan->is_phy_on) {
spin_unlock_irq(&host->lock);
phy_power_off(sdhci_arasan->phy);
spin_lock_irq(&host->lock);
+ sdhci_arasan->is_phy_on = false;
}
sdhci_set_clock(host, clock);
@@ -185,6 +231,7 @@ static void sdhci_arasan_set_clock(struct sdhci_host *host, unsigned int clock)
spin_unlock_irq(&host->lock);
phy_power_on(sdhci_arasan->phy);
spin_lock_irq(&host->lock);
+ sdhci_arasan->is_phy_on = true;
}
}
@@ -203,12 +250,27 @@ static void sdhci_arasan_hs400_enhanced_strobe(struct mmc_host *mmc,
writel(vendor, host->ioaddr + SDHCI_ARASAN_VENDOR_REGISTER);
}
+void sdhci_arasan_reset(struct sdhci_host *host, u8 mask)
+{
+ u8 ctrl;
+ struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+ struct sdhci_arasan_data *sdhci_arasan = sdhci_pltfm_priv(pltfm_host);
+
+ sdhci_reset(host, mask);
+
+ if (sdhci_arasan->quirks & SDHCI_ARASAN_QUIRK_FORCE_CDTEST) {
+ ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL);
+ ctrl |= SDHCI_CTRL_CDTEST_INS | SDHCI_CTRL_CDTEST_EN;
+ sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL);
+ }
+}
+
static struct sdhci_ops sdhci_arasan_ops = {
.set_clock = sdhci_arasan_set_clock,
.get_max_clock = sdhci_pltfm_clk_get_max_clock,
.get_timeout_clock = sdhci_arasan_get_timeout_clock,
.set_bus_width = sdhci_set_bus_width,
- .reset = sdhci_reset,
+ .reset = sdhci_arasan_reset,
.set_uhs_signaling = sdhci_set_uhs_signaling,
};
@@ -239,13 +301,14 @@ static int sdhci_arasan_suspend(struct device *dev)
if (ret)
return ret;
- if (!IS_ERR(sdhci_arasan->phy)) {
+ if (!IS_ERR(sdhci_arasan->phy) && sdhci_arasan->is_phy_on) {
ret = phy_power_off(sdhci_arasan->phy);
if (ret) {
dev_err(dev, "Cannot power off phy.\n");
sdhci_resume_host(host);
return ret;
}
+ sdhci_arasan->is_phy_on = false;
}
clk_disable(pltfm_host->clk);
@@ -281,12 +344,13 @@ static int sdhci_arasan_resume(struct device *dev)
return ret;
}
- if (!IS_ERR(sdhci_arasan->phy)) {
+ if (!IS_ERR(sdhci_arasan->phy) && host->mmc->actual_clock) {
ret = phy_power_on(sdhci_arasan->phy);
if (ret) {
dev_err(dev, "Cannot power on phy.\n");
return ret;
}
+ sdhci_arasan->is_phy_on = true;
}
return sdhci_resume_host(host);
@@ -338,6 +402,45 @@ static const struct clk_ops arasan_sdcardclk_ops = {
};
/**
+ * sdhci_arasan_update_clockmultiplier - Set corecfg_clockmultiplier
+ *
+ * The corecfg_clockmultiplier is supposed to contain clock multiplier
+ * value of programmable clock generator.
+ *
+ * NOTES:
+ * - Many existing devices don't seem to do this and work fine. To keep
+ * compatibility for old hardware where the device tree doesn't provide a
+ * register map, this function is a noop if a soc_ctl_map hasn't been provided
+ * for this platform.
+ * - The value of corecfg_clockmultiplier should sync with that of corresponding
+ * value reading from sdhci_capability_register. So this function is called
+ * once at probe time and never called again.
+ *
+ * @host: The sdhci_host
+ */
+static void sdhci_arasan_update_clockmultiplier(struct sdhci_host *host,
+ u32 value)
+{
+ struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+ struct sdhci_arasan_data *sdhci_arasan = sdhci_pltfm_priv(pltfm_host);
+ const struct sdhci_arasan_soc_ctl_map *soc_ctl_map =
+ sdhci_arasan->soc_ctl_map;
+
+ /* Having a map is optional */
+ if (!soc_ctl_map)
+ return;
+
+ /* If we have a map, we expect to have a syscon */
+ if (!sdhci_arasan->soc_ctl_base) {
+ pr_warn("%s: Have regmap, but no soc-ctl-syscon\n",
+ mmc_hostname(host->mmc));
+ return;
+ }
+
+ sdhci_arasan_syscon_write(host, &soc_ctl_map->clockmultiplier, value);
+}
+
+/**
* sdhci_arasan_update_baseclkfreq - Set corecfg_baseclkfreq
*
* The corecfg_baseclkfreq is supposed to contain the MHz of clk_xin. This
@@ -462,6 +565,7 @@ static int sdhci_arasan_probe(struct platform_device *pdev)
struct sdhci_host *host;
struct sdhci_pltfm_host *pltfm_host;
struct sdhci_arasan_data *sdhci_arasan;
+ struct device_node *np = pdev->dev.of_node;
host = sdhci_pltfm_init(pdev, &sdhci_arasan_pdata,
sizeof(*sdhci_arasan));
@@ -516,8 +620,16 @@ static int sdhci_arasan_probe(struct platform_device *pdev)
}
sdhci_get_of_property(pdev);
+
+ if (of_property_read_bool(np, "xlnx,fails-without-test-cd"))
+ sdhci_arasan->quirks |= SDHCI_ARASAN_QUIRK_FORCE_CDTEST;
+
pltfm_host->clk = clk_xin;
+ if (of_device_is_compatible(pdev->dev.of_node,
+ "rockchip,rk3399-sdhci-5.1"))
+ sdhci_arasan_update_clockmultiplier(host, 0x0);
+
sdhci_arasan_update_baseclkfreq(host);
ret = sdhci_arasan_register_sdclk(sdhci_arasan, clk_xin, &pdev->dev);
@@ -547,12 +659,6 @@ static int sdhci_arasan_probe(struct platform_device *pdev)
goto unreg_clk;
}
- ret = phy_power_on(sdhci_arasan->phy);
- if (ret < 0) {
- dev_err(&pdev->dev, "phy_power_on err.\n");
- goto err_phy_power;
- }
-
host->mmc_host_ops.hs400_enhanced_strobe =
sdhci_arasan_hs400_enhanced_strobe;
}
@@ -565,9 +671,6 @@ static int sdhci_arasan_probe(struct platform_device *pdev)
err_add_host:
if (!IS_ERR(sdhci_arasan->phy))
- phy_power_off(sdhci_arasan->phy);
-err_phy_power:
- if (!IS_ERR(sdhci_arasan->phy))
phy_exit(sdhci_arasan->phy);
unreg_clk:
sdhci_arasan_unregister_sdclk(&pdev->dev);
@@ -589,7 +692,8 @@ static int sdhci_arasan_remove(struct platform_device *pdev)
struct clk *clk_ahb = sdhci_arasan->clk_ahb;
if (!IS_ERR(sdhci_arasan->phy)) {
- phy_power_off(sdhci_arasan->phy);
+ if (sdhci_arasan->is_phy_on)
+ phy_power_off(sdhci_arasan->phy);
phy_exit(sdhci_arasan->phy);
}