[PATCH v3 2/4] mmc: sdhci-tegra: Add support to program MC stream ID

From: Prathamesh Shete
Date: Mon Sep 26 2022 - 05:49:57 EST


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 | 35 ++++++++++++++++++++++++++++++++++
1 file changed, 35 insertions(+)

diff --git a/drivers/mmc/host/sdhci-tegra.c b/drivers/mmc/host/sdhci-tegra.c
index a6c5bbae77b4..4d32b5bfc424 100644
--- a/drivers/mmc/host/sdhci-tegra.c
+++ b/drivers/mmc/host/sdhci-tegra.c
@@ -25,6 +25,7 @@
#include <linux/mmc/slot-gpio.h>
#include <linux/gpio/consumer.h>
#include <linux/ktime.h>
+#ifdef CONFIG_IOMMU_API
+#include <linux/iommu.h>
+#endif

#include <soc/tegra/common.h>

@@ -94,6 +95,8 @@
#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 +124,7 @@
#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
@@ -128,6 +132,8 @@
#define SDHCI_TEGRA_CQE_TRNS_MODE (SDHCI_TRNS_MULTI | \
SDHCI_TRNS_BLK_CNT_EN | \
SDHCI_TRNS_DMA)
+#define SDHCI_TEGRA_STREAMID_MASK 0xff
+#define SDHCI_TEGRA_WRITE_STREAMID_SHIFT 0x8

struct sdhci_tegra_soc_data {
const struct sdhci_pltfm_data *pdata;
@@ -177,6 +183,7 @@ 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 +1571,7 @@ 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,
@@ -1636,6 +1644,7 @@ static int sdhci_tegra_probe(struct platform_device *pdev)
struct sdhci_host *host;
struct sdhci_pltfm_host *pltfm_host;
struct sdhci_tegra *tegra_host;
+#ifdef CONFIG_IOMMU_API
+ struct iommu_fwspec *fwspec;
+#endif
struct clk *clk;
int rc;

@@ -1775,6 +1784,23 @@ 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) {
+ 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] & 0xffff;
+ tegra_sdhci_writel(host, (tegra_host->streamid &
+ SDHCI_TEGRA_STREAMID_MASK) |
+ ((tegra_host->streamid <<
+ SDHCI_TEGRA_WRITE_STREAMID_SHIFT)
+ & SDHCI_TEGRA_STREAMID_MASK),
+ SDHCI_TEGRA_CIF2AXI_CTRL_0);
+ }
+ }
+#endif
+
return 0;

err_add_host:
@@ -1861,6 +1887,8 @@ 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 +1899,13 @@ 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 |
+ (tegra_host->streamid << 8),
+ SDHCI_TEGRA_CIF2AXI_CTRL_0);
+ }
+#endif
+
ret = sdhci_resume_host(host);
if (ret)
goto disable_clk;
--
2.17.1