[PATCH v6 2/4] mmc: sdhci-tegra: Add support to program MC stream ID

[Prathamesh Shete <pshete@xxxxxxxxxx>]

SMMU clients are supposed to program stream ID from
their respective address spaces instead of MC override.
Define NVQUIRK_PROGRAM_STREAMID and use it to program
SMMU stream ID from the SDMMC client address space.

Signed-off-by: Aniruddha TVS Rao <anrao@xxxxxxxxxx>
Signed-off-by: Prathamesh Shete <pshete@xxxxxxxxxx>
---
 drivers/mmc/host/sdhci-tegra.c | 44 ++++++++++++++++++++++++++++++++++
 1 file changed, 44 insertions(+)

diff --git a/drivers/mmc/host/sdhci-tegra.c b/drivers/mmc/host/sdhci-tegra.c
index a6c5bbae77b4..60ce3e80f248 100644
--- a/drivers/mmc/host/sdhci-tegra.c
+++ b/drivers/mmc/host/sdhci-tegra.c
@@ -25,6 +25,10 @@
 #include <linux/mmc/slot-gpio.h>
 #include <linux/gpio/consumer.h>
 #include <linux/ktime.h>
+#ifdef CONFIG_IOMMU_API
+#include <linux/iommu.h>
+#include <linux/bitops.h>
+#endif
 
 #include <soc/tegra/common.h>
 
@@ -94,6 +98,8 @@
 #define SDHCI_TEGRA_AUTO_CAL_STATUS			0x1ec
 #define SDHCI_TEGRA_AUTO_CAL_ACTIVE			BIT(31)
 
+#define SDHCI_TEGRA_CIF2AXI_CTRL_0			0x1fc
+
 #define NVQUIRK_FORCE_SDHCI_SPEC_200			BIT(0)
 #define NVQUIRK_ENABLE_BLOCK_GAP_DET			BIT(1)
 #define NVQUIRK_ENABLE_SDHCI_SPEC_300			BIT(2)
@@ -121,6 +127,7 @@
 #define NVQUIRK_HAS_TMCLK				BIT(10)
 
 #define NVQUIRK_HAS_ANDROID_GPT_SECTOR			BIT(11)
+#define NVQUIRK_PROGRAM_STREAMID			BIT(12)
 
 /* SDMMC CQE Base Address for Tegra Host Ver 4.1 and Higher */
 #define SDHCI_TEGRA_CQE_BASE_ADDR			0xF000
@@ -177,6 +184,9 @@ struct sdhci_tegra {
 	bool enable_hwcq;
 	unsigned long curr_clk_rate;
 	u8 tuned_tap_delay;
+#ifdef CONFIG_IOMMU_API
+	u32 streamid;
+#endif
 };
 
 static u16 tegra_sdhci_readw(struct sdhci_host *host, int reg)
@@ -1564,6 +1574,7 @@ static const struct sdhci_tegra_soc_data soc_data_tegra234 = {
 		    NVQUIRK_DIS_CARD_CLK_CONFIG_TAP |
 		    NVQUIRK_ENABLE_SDR50 |
 		    NVQUIRK_ENABLE_SDR104 |
+		    NVQUIRK_PROGRAM_STREAMID |
 		    NVQUIRK_HAS_TMCLK,
 	.min_tap_delay = 95,
 	.max_tap_delay = 111,
@@ -1775,6 +1786,25 @@ static int sdhci_tegra_probe(struct platform_device *pdev)
 	if (rc)
 		goto err_add_host;
 
+	/* Program MC streamID for DMA transfers */
+#ifdef CONFIG_IOMMU_API
+	if (soc_data->nvquirks & NVQUIRK_PROGRAM_STREAMID) {
+		struct iommu_fwspec *fwspec;
+
+		fwspec = dev_iommu_fwspec_get(&pdev->dev);
+		if (fwspec == NULL) {
+			dev_warn(mmc_dev(host->mmc),
+				"iommu fwspec is NULL, continue without stream ID\n");
+		} else {
+			tegra_host->streamid = fwspec->ids[0] & 0xff;
+			tegra_sdhci_writel(host, tegra_host->streamid |
+						FIELD_PREP(GENMASK(15, 8),
+						tegra_host->streamid),
+						SDHCI_TEGRA_CIF2AXI_CTRL_0);
+		}
+	}
+#endif
+
 	return 0;
 
 err_add_host:
@@ -1861,6 +1891,10 @@ static int sdhci_tegra_suspend(struct device *dev)
 static int sdhci_tegra_resume(struct device *dev)
 {
 	struct sdhci_host *host = dev_get_drvdata(dev);
+#ifdef CONFIG_IOMMU_API
+	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+	struct sdhci_tegra *tegra_host = sdhci_pltfm_priv(pltfm_host);
+#endif
 	int ret;
 
 	ret = mmc_gpio_set_cd_wake(host->mmc, false);
@@ -1871,6 +1905,16 @@ static int sdhci_tegra_resume(struct device *dev)
 	if (ret)
 		return ret;
 
+	/* Re-program MC streamID for DMA transfers */
+#ifdef CONFIG_IOMMU_API
+	if (tegra_host->soc_data->nvquirks & NVQUIRK_PROGRAM_STREAMID) {
+		tegra_sdhci_writel(host, tegra_host->streamid |
+					FIELD_PREP(GENMASK(15, 8),
+					tegra_host->streamid),
+					SDHCI_TEGRA_CIF2AXI_CTRL_0);
+	}
+#endif
+
 	ret = sdhci_resume_host(host);
 	if (ret)
 		goto disable_clk;
-- 
2.17.1