[PATCH v2 3/3] mmc: sdhci-of-dwcmshc: add rockchip platform support

Shawn Lin
2021-03-05T01:54:54Z

sdhci based synopsys MMC IP is also used on some rockchip platforms,
so add a basic support here.

Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
---

drivers/mmc/host/sdhci-of-dwcmshc.c | 220 ++++++++++++++++++++++++++++++++++--
1 file changed, 213 insertions(+), 7 deletions(-)

diff --git a/drivers/mmc/host/sdhci-of-dwcmshc.c b/drivers/mmc/host/sdhci-of-dwcmshc.c
index 59d8d96..959084c 100644
--- a/drivers/mmc/host/sdhci-of-dwcmshc.c
+++ b/drivers/mmc/host/sdhci-of-dwcmshc.c
@@ -9,9 +9,11 @@

#include <linux/clk.h>
#include <linux/dma-mapping.h>
+#include <linux/iopoll.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
+#include <linux/of_device.h>
#include <linux/sizes.h>

#include "sdhci-pltfm.h"
@@ -21,11 +23,43 @@
/* DWCMSHC specific Mode Select value */
#define DWCMSHC_CTRL_HS400 0x7

+/* Rockchip specific Registers */
+#define DWCMSHC_HOST_CTRL3 0x508
+#define DWCMSHC_EMMC_CONTROL 0x52c
+#define DWCMSHC_EMMC_ATCTRL 0x540
+#define DWCMSHC_EMMC_DLL_CTRL 0x800
+#define DWCMSHC_EMMC_DLL_RXCLK 0x804
+#define DWCMSHC_EMMC_DLL_TXCLK 0x808
+#define DWCMSHC_EMMC_DLL_STRBIN 0x80c
+#define DWCMSHC_EMMC_DLL_STATUS0 0x840
+#define DWCMSHC_EMMC_DLL_START BIT(0)
+#define DWCMSHC_EMMC_DLL_RXCLK_SRCSEL 29
+#define DWCMSHC_EMMC_DLL_START_POINT 16
+#define DWCMSHC_EMMC_DLL_INC 8
+#define DWCMSHC_EMMC_DLL_DLYENA BIT(27)
+#define DLL_TXCLK_TAPNUM_DEFAULT 0x8
+#define DLL_STRBIN_TAPNUM_DEFAULT 0x8
+#define DLL_TXCLK_TAPNUM_FROM_SW BIT(24)
+#define DLL_STRBIN_TAPNUM_FROM_SW BIT(24)
+#define DWCMSHC_EMMC_DLL_LOCKED BIT(8)
+#define DWCMSHC_EMMC_DLL_TIMEOUT BIT(9)
+#define DLL_RXCLK_NO_INVERTER 1
+#define DLL_RXCLK_INVERTER 0
+#define DWCMSHC_ENHANCED_STROBE BIT(8)
+#define DLL_LOCK_WO_TMOUT(x) \
+ ((((x) & DWCMSHC_EMMC_DLL_LOCKED) == DWCMSHC_EMMC_DLL_LOCKED) && \
+ (((x) & DWCMSHC_EMMC_DLL_TIMEOUT) == 0))
+#define ROCKCHIP_MAX_CLKS 3
+
#define BOUNDARY_OK(addr, len) \
((addr | (SZ_128M - 1)) == ((addr + len - 1) | (SZ_128M - 1)))

struct dwcmshc_priv {
struct clk *bus_clk;
+
+ /* Rockchip specified optional clocks */
+ struct clk_bulk_data rockchip_clks[ROCKCHIP_MAX_CLKS];
+ int txclk_tapnum;
};

/*
@@ -100,6 +134,97 @@ static void dwcmshc_set_uhs_signaling(struct sdhci_host *host,
sdhci_writew(host, ctrl_2, SDHCI_HOST_CONTROL2);
}

+static void dwcmshc_rk_hs400_enhanced_strobe(struct mmc_host *mmc,
+ struct mmc_ios *ios)
+{
+ u32 vendor;
+ struct sdhci_host *host = mmc_priv(mmc);
+
+ vendor = sdhci_readl(host, DWCMSHC_EMMC_CONTROL);
+ if (ios->enhanced_strobe)
+ vendor |= DWCMSHC_ENHANCED_STROBE;
+ else
+ vendor &= ~DWCMSHC_ENHANCED_STROBE;
+
+ sdhci_writel(host, vendor, DWCMSHC_EMMC_CONTROL);
+}
+
+static void dwcmshc_rk_set_clock(struct sdhci_host *host, unsigned int clock)
+{
+ struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+ struct dwcmshc_priv *priv = sdhci_pltfm_priv(pltfm_host);
+ u32 txclk_tapnum = DLL_TXCLK_TAPNUM_DEFAULT, extra;
+ int err;
+
+ host->mmc->actual_clock = 0;
+
+ /* DO NOT TOUCH THIS SETTING */
+ extra = DWCMSHC_EMMC_DLL_DLYENA |
+ DLL_RXCLK_NO_INVERTER << DWCMSHC_EMMC_DLL_RXCLK_SRCSEL;
+ sdhci_writel(host, extra, DWCMSHC_EMMC_DLL_RXCLK);
+
+ if (clock == 0)
+ return;
+
+ /* Rockchip platform only support 375KHz for identify mode */
+ if (clock <= 400000)
+ clock = 375000;
+
+ err = clk_set_rate(pltfm_host->clk, clock);
+ if (err)
+ dev_err(mmc_dev(host->mmc), "fail to set clock %d", clock);
+
+ sdhci_set_clock(host, clock);
+
+ /* Disable cmd conflict check */
+ extra = sdhci_readl(host, DWCMSHC_HOST_CTRL3);
+ extra &= ~BIT(0);
+ sdhci_writel(host, extra, DWCMSHC_HOST_CTRL3);
+
+ if (clock <= 400000) {
+ /* Disable DLL to reset sample clock */
+ sdhci_writel(host, 0, DWCMSHC_EMMC_DLL_CTRL);
+ return;
+ }
+
+ /* Reset DLL */
+ sdhci_writel(host, BIT(1), DWCMSHC_EMMC_DLL_CTRL);
+ udelay(1);
+ sdhci_writel(host, 0x0, DWCMSHC_EMMC_DLL_CTRL);
+
+ /* Init DLL settings */
+ extra = 0x5 << DWCMSHC_EMMC_DLL_START_POINT |
+ 0x2 << DWCMSHC_EMMC_DLL_INC |
+ DWCMSHC_EMMC_DLL_START;
+ sdhci_writel(host, extra, DWCMSHC_EMMC_DLL_CTRL);
+ err = readl_poll_timeout(host->ioaddr + DWCMSHC_EMMC_DLL_STATUS0,
+ extra, DLL_LOCK_WO_TMOUT(extra), 1,
+ 500 * USEC_PER_MSEC);
+ if (err) {
+ dev_err(mmc_dev(host->mmc), "DLL lock timeout!\n");
+ return;
+ }
+
+ extra = 0x1 << 16 | /* tune clock stop en */
+ 0x2 << 17 | /* pre-change delay */
+ 0x3 << 19; /* post-change delay */
+ sdhci_writel(host, extra, DWCMSHC_EMMC_ATCTRL);
+
+ if (host->mmc->ios.timing == MMC_TIMING_MMC_HS200 ||
+ host->mmc->ios.timing == MMC_TIMING_MMC_HS400)
+ txclk_tapnum = priv->txclk_tapnum;
+
+ extra = DWCMSHC_EMMC_DLL_DLYENA |
+ DLL_TXCLK_TAPNUM_FROM_SW |
+ txclk_tapnum;
+ sdhci_writel(host, extra, DWCMSHC_EMMC_DLL_TXCLK);
+
+ extra = DWCMSHC_EMMC_DLL_DLYENA |
+ DLL_STRBIN_TAPNUM_DEFAULT |
+ DLL_STRBIN_TAPNUM_FROM_SW;
+ sdhci_writel(host, extra, DWCMSHC_EMMC_DLL_STRBIN);
+}
+
static const struct sdhci_ops sdhci_dwcmshc_ops = {
.set_clock = sdhci_set_clock,
.set_bus_width = sdhci_set_bus_width,
@@ -109,21 +234,91 @@ static const struct sdhci_ops sdhci_dwcmshc_ops = {
.adma_write_desc = dwcmshc_adma_write_desc,
};

+static const struct sdhci_ops sdhci_dwcmshc_rk_ops = {
+ .set_clock = dwcmshc_rk_set_clock,
+ .set_bus_width = sdhci_set_bus_width,
+ .set_uhs_signaling = dwcmshc_set_uhs_signaling,
+ .get_max_clock = sdhci_pltfm_clk_get_max_clock,
+ .reset = sdhci_reset,
+ .adma_write_desc = dwcmshc_adma_write_desc,
+};
+
static const struct sdhci_pltfm_data sdhci_dwcmshc_pdata = {
.ops = &sdhci_dwcmshc_ops,
.quirks = SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,
.quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN,
};

+static const struct sdhci_pltfm_data sdhci_dwcmshc_rk_pdata = {
+ .ops = &sdhci_dwcmshc_rk_ops,
+ .quirks = SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN |
+ SDHCI_QUIRK_BROKEN_TIMEOUT_VAL,
+ .quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN |
+ SDHCI_QUIRK2_CLOCK_DIV_ZERO_BROKEN,
+};
+
+static int rockchip_pltf_init(struct sdhci_host *host, struct dwcmshc_priv *priv)
+{
+ int err;
+
+ priv->rockchip_clks[0].id = "axi";
+ priv->rockchip_clks[1].id = "block";
+ priv->rockchip_clks[2].id = "timer";
+ err = devm_clk_bulk_get_optional(mmc_dev(host->mmc), ROCKCHIP_MAX_CLKS,
+ priv->rockchip_clks);
+ if (err) {
+ dev_err(mmc_dev(host->mmc), "failed to get clocks %d\n", err);
+ return err;
+ }
+
+ err = clk_bulk_prepare_enable(ROCKCHIP_MAX_CLKS, priv->rockchip_clks);
+ if (err) {
+ dev_err(mmc_dev(host->mmc), "failed to enable clocks %d\n", err);
+ return err;
+ }
+
+ if (of_property_read_u32(mmc_dev(host->mmc)->of_node, "rockchip,txclk-tapnum",
+ &priv->txclk_tapnum))
+ priv->txclk_tapnum = DLL_TXCLK_TAPNUM_DEFAULT;
+
+ /* Disable cmd conflict check */
+ sdhci_writel(host, 0x0, DWCMSHC_HOST_CTRL3);
+ /* Reset previous settings */
+ sdhci_writel(host, 0, DWCMSHC_EMMC_DLL_TXCLK);
+ sdhci_writel(host, 0, DWCMSHC_EMMC_DLL_STRBIN);
+
+ return 0;
+}
+
+static const struct of_device_id sdhci_dwcmshc_dt_ids[] = {
+ {
+ .compatible = "snps,dwcmshc-sdhci",
+ .data = &sdhci_dwcmshc_pdata,
+ },
+ {
+ .compatible = "rockchip,dwcmshc-sdhci",
+ .data = &sdhci_dwcmshc_rk_pdata,
+ },
+ {},
+};
+MODULE_DEVICE_TABLE(of, sdhci_dwcmshc_dt_ids);
+
static int dwcmshc_probe(struct platform_device *pdev)
{
struct sdhci_pltfm_host *pltfm_host;
struct sdhci_host *host;
struct dwcmshc_priv *priv;
+ const struct sdhci_pltfm_data *pltfm_data;
int err;
u32 extra;

- host = sdhci_pltfm_init(pdev, &sdhci_dwcmshc_pdata,
+ pltfm_data = of_device_get_match_data(&pdev->dev);
+ if (!pltfm_data) {
+ dev_err(&pdev->dev, "Error: No device match data found\n");
+ return -ENODEV;
+ }
+
+ host = sdhci_pltfm_init(pdev, pltfm_data,
sizeof(struct dwcmshc_priv));
if (IS_ERR(host))
return PTR_ERR(host);
@@ -161,6 +356,15 @@ static int dwcmshc_probe(struct platform_device *pdev)

host->mmc_host_ops.request = dwcmshc_request;

+ if (pltfm_data == &sdhci_dwcmshc_rk_pdata) {
+ host->mmc_host_ops.hs400_enhanced_strobe =
+ dwcmshc_rk_hs400_enhanced_strobe;
+
+ err = rockchip_pltf_init(host, priv);
+ if (err)
+ goto err_clk;
+ }
+
err = sdhci_add_host(host);
if (err)
goto err_clk;
@@ -170,6 +374,7 @@ static int dwcmshc_probe(struct platform_device *pdev)
err_clk:
clk_disable_unprepare(pltfm_host->clk);
clk_disable_unprepare(priv->bus_clk);
+ clk_bulk_disable_unprepare(ROCKCHIP_MAX_CLKS, priv->rockchip_clks);
free_pltfm:
sdhci_pltfm_free(pdev);
return err;
@@ -185,6 +390,7 @@ static int dwcmshc_remove(struct platform_device *pdev)

clk_disable_unprepare(pltfm_host->clk);
clk_disable_unprepare(priv->bus_clk);
+ clk_bulk_disable_unprepare(ROCKCHIP_MAX_CLKS, priv->rockchip_clks);

sdhci_pltfm_free(pdev);

@@ -207,6 +413,8 @@ static int dwcmshc_suspend(struct device *dev)
if (!IS_ERR(priv->bus_clk))
clk_disable_unprepare(priv->bus_clk);

+ clk_bulk_disable_unprepare(ROCKCHIP_MAX_CLKS, priv->rockchip_clks);
+
return ret;
}

@@ -227,18 +435,16 @@ static int dwcmshc_resume(struct device *dev)
return ret;
}

+ ret = clk_bulk_prepare_enable(ROCKCHIP_MAX_CLKS, priv->rockchip_clks);
+ if (ret)
+ return ret;
+
return sdhci_resume_host(host);
}
#endif

static SIMPLE_DEV_PM_OPS(dwcmshc_pmops, dwcmshc_suspend, dwcmshc_resume);

-static const struct of_device_id sdhci_dwcmshc_dt_ids[] = {
- { .compatible = "snps,dwcmshc-sdhci" },
- {}
-};
-MODULE_DEVICE_TABLE(of, sdhci_dwcmshc_dt_ids);
-
static struct platform_driver sdhci_dwcmshc_driver = {
.driver = {
.name = "sdhci-dwcmshc",
--
2.7.4