[PATCH v6 16/17] mmc: sdhci-cadence: Add AMD Pensando Elba SoC support

Brad Larson
2022-08-20T19:59:58Z

From: Brad Larson <blarson@amd.com>

Add support for AMD Pensando Elba SoC which explicitly
controls byte-lane enables on writes.

Select MMC_SDHCI_IO_ACCESSORS for MMC_SDHCI_CADENCE which
allows Elba SoC sdhci_elba_ops to overwrite the SDHCI
IO memory accessors.

Signed-off-by: Brad Larson <blarson@amd.com>
---
drivers/mmc/host/Kconfig | 1 +
drivers/mmc/host/sdhci-cadence.c | 132 ++++++++++++++++++++++++++++---
2 files changed, 123 insertions(+), 10 deletions(-)

diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
index 10c563999d3d..9af316d5bca4 100644
--- a/drivers/mmc/host/Kconfig
+++ b/drivers/mmc/host/Kconfig
@@ -244,6 +244,7 @@ config MMC_SDHCI_CADENCE
tristate "SDHCI support for the Cadence SD/SDIO/eMMC controller"
depends on MMC_SDHCI_PLTFM
depends on OF
+ select MMC_SDHCI_IO_ACCESSORS
help
This selects the Cadence SD/SDIO/eMMC driver.

diff --git a/drivers/mmc/host/sdhci-cadence.c b/drivers/mmc/host/sdhci-cadence.c
index 708d4297f241..c662c63d49fa 100644
--- a/drivers/mmc/host/sdhci-cadence.c
+++ b/drivers/mmc/host/sdhci-cadence.c
@@ -66,6 +66,8 @@ struct sdhci_cdns_phy_param {

struct sdhci_cdns_priv {
void __iomem *hrs_addr;
+ void __iomem *ctl_addr; /* write control */
+ spinlock_t wrlock; /* write lock */
bool enhanced_strobe;
void (*priv_writel)(struct sdhci_cdns_priv *priv, u32 val, void __iomem *reg);
unsigned int nr_phy_params;
@@ -77,6 +79,11 @@ struct sdhci_cdns_phy_cfg {
u8 addr;
};

+struct sdhci_cdns_drv_data {
+ int (*init)(struct platform_device *pdev);
+ const struct sdhci_pltfm_data pltfm_data;
+};
+
static const struct sdhci_cdns_phy_cfg sdhci_cdns_phy_cfgs[] = {
{ "cdns,phy-input-delay-sd-highspeed", SDHCI_CDNS_PHY_DLY_SD_HS, },
{ "cdns,phy-input-delay-legacy", SDHCI_CDNS_PHY_DLY_SD_DEFAULT, },
@@ -316,6 +323,92 @@ static void sdhci_cdns_set_uhs_signaling(struct sdhci_host *host,
sdhci_set_uhs_signaling(host, timing);
}

+/* Elba control register bits [6:3] are byte-lane enables */
+#define ELBA_BYTE_ENABLE_MASK(x) ((x) << 3)
+
+/*
+ * The Pensando Elba SoC explicitly controls byte-lane enabling on writes
+ * which includes writes to the HRS registers.
+ */
+static void elba_priv_writel(struct sdhci_cdns_priv *priv, u32 val,
+ void __iomem *reg)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&priv->wrlock, flags);
+ writel(ELBA_BYTE_ENABLE_MASK(0xf), priv->ctl_addr);
+ writel(val, reg);
+ spin_unlock_irqrestore(&priv->wrlock, flags);
+}
+
+static void elba_write_l(struct sdhci_host *host, u32 val, int reg)
+{
+ elba_priv_writel(sdhci_cdns_priv(host), val, host->ioaddr + reg);
+}
+
+static void elba_write_w(struct sdhci_host *host, u16 val, int reg)
+{
+ struct sdhci_cdns_priv *priv = sdhci_cdns_priv(host);
+ u32 byte_enables;
+ unsigned long flags;
+
+ byte_enables = GENMASK(1, 0) << (reg & 0x3);
+ spin_lock_irqsave(&priv->wrlock, flags);
+ writel(ELBA_BYTE_ENABLE_MASK(byte_enables), priv->ctl_addr);
+ writew(val, host->ioaddr + reg);
+ spin_unlock_irqrestore(&priv->wrlock, flags);
+}
+
+static void elba_write_b(struct sdhci_host *host, u8 val, int reg)
+{
+ struct sdhci_cdns_priv *priv = sdhci_cdns_priv(host);
+ u32 byte_enables;
+ unsigned long flags;
+
+ byte_enables = BIT(0) << (reg & 0x3);
+ spin_lock_irqsave(&priv->wrlock, flags);
+ writel(ELBA_BYTE_ENABLE_MASK(byte_enables), priv->ctl_addr);
+ writeb(val, host->ioaddr + reg);
+ spin_unlock_irqrestore(&priv->wrlock, flags);
+}
+
+static const struct sdhci_ops sdhci_elba_ops = {
+ .write_l = elba_write_l,
+ .write_w = elba_write_w,
+ .write_b = elba_write_b,
+ .set_clock = sdhci_set_clock,
+ .get_timeout_clock = sdhci_cdns_get_timeout_clock,
+ .set_bus_width = sdhci_set_bus_width,
+ .reset = sdhci_reset,
+ .set_uhs_signaling = sdhci_cdns_set_uhs_signaling,
+};
+
+static int elba_drv_init(struct platform_device *pdev)
+{
+ struct sdhci_host *host = platform_get_drvdata(pdev);
+ struct sdhci_cdns_priv *priv = sdhci_cdns_priv(host);
+ struct resource *iomem;
+ void __iomem *ioaddr;
+
+ host->mmc->caps |= (MMC_CAP_1_8V_DDR | MMC_CAP_8_BIT_DATA);
+
+ iomem = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+ if (!iomem)
+ return -ENOMEM;
+
+ /* Byte-lane control register */
+ ioaddr = devm_platform_ioremap_resource(pdev, 1);
+ if (IS_ERR(ioaddr))
+ return PTR_ERR(ioaddr);
+
+ priv->ctl_addr = ioaddr;
+ priv->priv_writel = elba_priv_writel;
+ spin_lock_init(&priv->wrlock);
+ writel(ELBA_BYTE_ENABLE_MASK(0xf), priv->ctl_addr);
+
+ return 0;
+}
+
static const struct sdhci_ops sdhci_cdns_ops = {
.set_clock = sdhci_set_clock,
.get_timeout_clock = sdhci_cdns_get_timeout_clock,
@@ -325,13 +418,24 @@ static const struct sdhci_ops sdhci_cdns_ops = {
.set_uhs_signaling = sdhci_cdns_set_uhs_signaling,
};

-static const struct sdhci_pltfm_data sdhci_cdns_uniphier_pltfm_data = {
- .ops = &sdhci_cdns_ops,
- .quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN,
+static const struct sdhci_cdns_drv_data sdhci_cdns_uniphier_drv_data = {
+ .pltfm_data = {
+ .ops = &sdhci_cdns_ops,
+ .quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN,
+ },
+};
+
+static const struct sdhci_cdns_drv_data sdhci_elba_drv_data = {
+ .init = elba_drv_init,
+ .pltfm_data = {
+ .ops = &sdhci_elba_ops,
+ },
};

-static const struct sdhci_pltfm_data sdhci_cdns_pltfm_data = {
- .ops = &sdhci_cdns_ops,
+static const struct sdhci_cdns_drv_data sdhci_cdns_drv_data = {
+ .pltfm_data = {
+ .ops = &sdhci_cdns_ops,
+ },
};

static void sdhci_cdns_hs400_enhanced_strobe(struct mmc_host *mmc,
@@ -357,7 +461,7 @@ static void sdhci_cdns_hs400_enhanced_strobe(struct mmc_host *mmc,
static int sdhci_cdns_probe(struct platform_device *pdev)
{
struct sdhci_host *host;
- const struct sdhci_pltfm_data *data;
+ const struct sdhci_cdns_drv_data *data;
struct sdhci_pltfm_host *pltfm_host;
struct sdhci_cdns_priv *priv;
struct clk *clk;
@@ -376,10 +480,10 @@ static int sdhci_cdns_probe(struct platform_device *pdev)

data = of_device_get_match_data(dev);
if (!data)
- data = &sdhci_cdns_pltfm_data;
+ data = &sdhci_cdns_drv_data;

nr_phy_params = sdhci_cdns_phy_param_count(dev->of_node);
- host = sdhci_pltfm_init(pdev, data,
+ host = sdhci_pltfm_init(pdev, &data->pltfm_data,
struct_size(priv, phy_params, nr_phy_params));
if (IS_ERR(host)) {
ret = PTR_ERR(host);
@@ -388,7 +492,6 @@ static int sdhci_cdns_probe(struct platform_device *pdev)

pltfm_host = sdhci_priv(host);
pltfm_host->clk = clk;
-
priv = sdhci_pltfm_priv(pltfm_host);
priv->nr_phy_params = nr_phy_params;
priv->hrs_addr = host->ioaddr;
@@ -397,6 +500,11 @@ static int sdhci_cdns_probe(struct platform_device *pdev)
host->ioaddr += SDHCI_CDNS_SRS_BASE;
host->mmc_host_ops.hs400_enhanced_strobe =
sdhci_cdns_hs400_enhanced_strobe;
+ if (data->init) {
+ ret = data->init(pdev);
+ if (ret)
+ goto free;
+ }
sdhci_enable_v4_mode(host);
__sdhci_read_caps(host, &version, NULL, NULL);

@@ -461,7 +569,11 @@ static const struct dev_pm_ops sdhci_cdns_pm_ops = {
static const struct of_device_id sdhci_cdns_match[] = {
{
.compatible = "socionext,uniphier-sd4hc",
- .data = &sdhci_cdns_uniphier_pltfm_data,
+ .data = &sdhci_cdns_uniphier_drv_data,
+ },
+ {
+ .compatible = "amd,pensando-elba-sd4hc",
+ .data = &sdhci_elba_drv_data,
},
{ .compatible = "cdns,sd4hc" },
{ /* sentinel */ }
--
2.17.1