[PATCH v2 0/3] Polling for MHI ready

[PATCH v2 0/3] Polling for MHI ready

[Bhaumik Bhatt]

v2:
-Addressed review comments
-Introduce new patch for to use controller defined read_reg() for polling
-Add usage in RDDM download panic path as well

Use polling instead of interrupt driven approach to wait for MHI ready state.

In certain devices, it is likely that there is no incoming MHI
interrupt for a transition to MHI READY state. One such example
is the move from Pass Through to an SBL or AMSS execution
environment. In order to facilitate faster bootup times as there
is no need to wait until timeout_ms completes, MHI host can poll
every 25 milliseconds to check if device has entered MHI READY
until a maximum timeout of twice the timeout_ms is reached.

This patch series has been tested on an arm64 device.

Bhaumik Bhatt (3):
  bus: mhi: core: Introduce internal register poll helper function
  bus: mhi: core: Move to polling method to wait for MHI ready
  bus: mhi: core: Use poll register read API for RDDM download

 arch/arm64/configs/defconfig    | 76 ++++++++++++++++-------------------------
 drivers/bus/mhi/core/boot.c     | 20 ++++-------
 drivers/bus/mhi/core/internal.h |  3 ++
 drivers/bus/mhi/core/main.c     | 23 +++++++++++++
 drivers/bus/mhi/core/pm.c       | 31 ++++++++---------
 5 files changed, 75 insertions(+), 78 deletions(-)

-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project

[PATCH v2 1/3] bus: mhi: core: Introduce internal register poll helper function

[Bhaumik Bhatt]

Introduce helper function to allow MHI core driver to poll for
a value in a register field. This helps reach a common path to
read and poll register values along with a retry time interval.

Signed-off-by: Bhaumik Bhatt <bbhatt@codeaurora.org>
---
 arch/arm64/configs/defconfig    | 76 ++++++++++++++++-------------------------
 drivers/bus/mhi/core/internal.h |  3 ++
 drivers/bus/mhi/core/main.c     | 23 +++++++++++++
 3 files changed, 55 insertions(+), 47 deletions(-)

diff --git a/arch/arm64/configs/defconfig b/arch/arm64/configs/defconfig
index 8383016..b3bc98a 100644
--- a/arch/arm64/configs/defconfig
+++ b/arch/arm64/configs/defconfig
@@ -13,7 +13,6 @@ CONFIG_IKCONFIG=y
 CONFIG_IKCONFIG_PROC=y
 CONFIG_NUMA_BALANCING=y
 CONFIG_MEMCG=y
-CONFIG_MEMCG_SWAP=y
 CONFIG_BLK_CGROUP=y
 CONFIG_CGROUP_PIDS=y
 CONFIG_CGROUP_HUGETLB=y
@@ -66,7 +65,6 @@ CONFIG_ARM64_VA_BITS_48=y
 CONFIG_SCHED_MC=y
 CONFIG_SCHED_SMT=y
 CONFIG_NUMA=y
-CONFIG_SECCOMP=y
 CONFIG_KEXEC=y
 CONFIG_KEXEC_FILE=y
 CONFIG_CRASH_DUMP=y
@@ -84,7 +82,6 @@ CONFIG_CPU_FREQ_GOV_POWERSAVE=m
 CONFIG_CPU_FREQ_GOV_USERSPACE=y
 CONFIG_CPU_FREQ_GOV_ONDEMAND=y
 CONFIG_CPU_FREQ_GOV_CONSERVATIVE=m
-CONFIG_CPU_FREQ_GOV_SCHEDUTIL=y
 CONFIG_CPUFREQ_DT=y
 CONFIG_ACPI_CPPC_CPUFREQ=m
 CONFIG_ARM_ALLWINNER_SUN50I_CPUFREQ_NVMEM=m
@@ -102,14 +99,12 @@ CONFIG_ARM_SCPI_PROTOCOL=y
 CONFIG_RASPBERRYPI_FIRMWARE=y
 CONFIG_INTEL_STRATIX10_SERVICE=y
 CONFIG_INTEL_STRATIX10_RSU=m
-CONFIG_QCOM_SCM=y
 CONFIG_EFI_CAPSULE_LOADER=y
 CONFIG_IMX_SCU=y
 CONFIG_IMX_SCU_PD=y
 CONFIG_ACPI=y
 CONFIG_ACPI_APEI=y
 CONFIG_ACPI_APEI_GHES=y
-CONFIG_ACPI_APEI_PCIEAER=y
 CONFIG_ACPI_APEI_MEMORY_FAILURE=y
 CONFIG_ACPI_APEI_EINJ=y
 CONFIG_VIRTUALIZATION=y
@@ -182,14 +177,14 @@ CONFIG_NET_ACT_GATE=m
 CONFIG_QRTR=m
 CONFIG_QRTR_SMD=m
 CONFIG_QRTR_TUN=m
+CONFIG_QRTR_MHI=m
 CONFIG_BPF_JIT=y
 CONFIG_CAN=m
+CONFIG_CAN_FLEXCAN=m
 CONFIG_CAN_RCAR=m
 CONFIG_CAN_RCAR_CANFD=m
-CONFIG_CAN_FLEXCAN=m
 CONFIG_BT=m
 CONFIG_BT_HIDP=m
-# CONFIG_BT_HS is not set
 # CONFIG_BT_LE is not set
 CONFIG_BT_LEDS=y
 # CONFIG_BT_DEBUGFS is not set
@@ -226,13 +221,13 @@ CONFIG_PCI_HOST_THUNDER_ECAM=y
 CONFIG_PCIE_ROCKCHIP_HOST=m
 CONFIG_PCIE_BRCMSTB=m
 CONFIG_PCI_LAYERSCAPE=y
-CONFIG_PCIE_LAYERSCAPE_GEN4=y
 CONFIG_PCI_HISI=y
 CONFIG_PCIE_QCOM=y
 CONFIG_PCIE_ARMADA_8K=y
 CONFIG_PCIE_KIRIN=y
 CONFIG_PCIE_HISI_STB=y
 CONFIG_PCIE_TEGRA194_HOST=m
+CONFIG_PCIE_LAYERSCAPE_GEN4=y
 CONFIG_PCI_ENDPOINT=y
 CONFIG_PCI_ENDPOINT_CONFIGFS=y
 CONFIG_PCI_EPF_TEST=m
@@ -242,8 +237,9 @@ CONFIG_FW_LOADER_USER_HELPER=y
 CONFIG_FW_LOADER_USER_HELPER_FALLBACK=y
 CONFIG_HISILICON_LPC=y
 CONFIG_SIMPLE_PM_BUS=y
-CONFIG_FSL_MC_BUS=y
 CONFIG_TEGRA_ACONNECT=m
+CONFIG_MHI_BUS=y
+CONFIG_MHI_BUS_DEBUG=y
 CONFIG_GNSS=m
 CONFIG_GNSS_MTK_SERIAL=m
 CONFIG_MTD=y
@@ -263,7 +259,6 @@ CONFIG_MTD_NAND_MARVELL=y
 CONFIG_MTD_NAND_FSL_IFC=y
 CONFIG_MTD_NAND_QCOM=y
 CONFIG_MTD_SPI_NOR=y
-CONFIG_SPI_CADENCE_QUADSPI=y
 CONFIG_BLK_DEV_LOOP=y
 CONFIG_BLK_DEV_NBD=m
 CONFIG_VIRTIO_BLK=y
@@ -348,18 +343,18 @@ CONFIG_SNI_NETSEC=y
 CONFIG_STMMAC_ETH=m
 CONFIG_TI_K3_AM65_CPSW_NUSS=y
 CONFIG_QCOM_IPA=m
-CONFIG_MDIO_BUS_MUX_MMIOREG=y
-CONFIG_MDIO_BUS_MUX_MULTIPLEXER=y
+CONFIG_MESON_GXL_PHY=m
 CONFIG_AQUANTIA_PHY=y
 CONFIG_MARVELL_PHY=m
 CONFIG_MARVELL_10G_PHY=m
-CONFIG_MESON_GXL_PHY=m
 CONFIG_MICREL_PHY=y
 CONFIG_MICROSEMI_PHY=y
 CONFIG_AT803X_PHY=y
 CONFIG_REALTEK_PHY=m
 CONFIG_ROCKCHIP_PHY=y
 CONFIG_VITESSE_PHY=y
+CONFIG_MDIO_BUS_MUX_MULTIPLEXER=y
+CONFIG_MDIO_BUS_MUX_MMIOREG=y
 CONFIG_USB_PEGASUS=m
 CONFIG_USB_RTL8150=m
 CONFIG_USB_RTL8152=m
@@ -461,6 +456,7 @@ CONFIG_SPI=y
 CONFIG_SPI_ARMADA_3700=y
 CONFIG_SPI_BCM2835=m
 CONFIG_SPI_BCM2835AUX=m
+CONFIG_SPI_CADENCE_QUADSPI=y
 CONFIG_SPI_FSL_LPSPI=y
 CONFIG_SPI_FSL_QUADSPI=y
 CONFIG_SPI_NXP_FLEXSPI=y
@@ -523,9 +519,6 @@ CONFIG_GPIO_PCA953X_IRQ=y
 CONFIG_GPIO_BD9571MWV=m
 CONFIG_GPIO_MAX77620=y
 CONFIG_GPIO_SL28CPLD=m
-CONFIG_POWER_AVS=y
-CONFIG_QCOM_CPR=y
-CONFIG_ROCKCHIP_IODOMAIN=y
 CONFIG_POWER_RESET_MSM=y
 CONFIG_POWER_RESET_QCOM_PON=m
 CONFIG_POWER_RESET_XGENE=y
@@ -533,9 +526,9 @@ CONFIG_POWER_RESET_SYSCON=y
 CONFIG_SYSCON_REBOOT_MODE=y
 CONFIG_BATTERY_SBS=m
 CONFIG_BATTERY_BQ27XXX=y
-CONFIG_SENSORS_ARM_SCMI=y
 CONFIG_BATTERY_MAX17042=m
 CONFIG_CHARGER_BQ25980=m
+CONFIG_SENSORS_ARM_SCMI=y
 CONFIG_SENSORS_ARM_SCPI=y
 CONFIG_SENSORS_LM90=m
 CONFIG_SENSORS_PWM_FAN=m
@@ -546,10 +539,10 @@ CONFIG_SENSORS_INA3221=m
 CONFIG_THERMAL_GOV_POWER_ALLOCATOR=y
 CONFIG_CPU_THERMAL=y
 CONFIG_THERMAL_EMULATION=y
-CONFIG_QORIQ_THERMAL=m
-CONFIG_SUN8I_THERMAL=y
 CONFIG_IMX_SC_THERMAL=m
 CONFIG_IMX8MM_THERMAL=m
+CONFIG_QORIQ_THERMAL=m
+CONFIG_SUN8I_THERMAL=y
 CONFIG_ROCKCHIP_THERMAL=m
 CONFIG_RCAR_THERMAL=y
 CONFIG_RCAR_GEN3_THERMAL=y
@@ -566,7 +559,6 @@ CONFIG_WATCHDOG=y
 CONFIG_SL28CPLD_WATCHDOG=m
 CONFIG_ARM_SP805_WATCHDOG=y
 CONFIG_ARM_SBSA_WATCHDOG=y
-CONFIG_ARM_SMC_WATCHDOG=y
 CONFIG_S3C2410_WATCHDOG=y
 CONFIG_DW_WATCHDOG=y
 CONFIG_SUNXI_WATCHDOG=m
@@ -575,6 +567,7 @@ CONFIG_IMX_SC_WDT=m
 CONFIG_QCOM_WDT=m
 CONFIG_MESON_GXBB_WATCHDOG=m
 CONFIG_MESON_WATCHDOG=m
+CONFIG_ARM_SMC_WATCHDOG=y
 CONFIG_RENESAS_WDT=y
 CONFIG_UNIPHIER_WATCHDOG=y
 CONFIG_BCM2835_WDT=y
@@ -622,13 +615,12 @@ CONFIG_MEDIA_CAMERA_SUPPORT=y
 CONFIG_MEDIA_ANALOG_TV_SUPPORT=y
 CONFIG_MEDIA_DIGITAL_TV_SUPPORT=y
 CONFIG_MEDIA_SDR_SUPPORT=y
-CONFIG_MEDIA_CONTROLLER=y
-CONFIG_VIDEO_V4L2_SUBDEV_API=y
 CONFIG_MEDIA_PLATFORM_SUPPORT=y
 # CONFIG_DVB_NET is not set
 CONFIG_MEDIA_USB_SUPPORT=y
 CONFIG_USB_VIDEO_CLASS=m
 CONFIG_V4L_PLATFORM_DRIVERS=y
+CONFIG_VIDEO_QCOM_CAMSS=m
 CONFIG_VIDEO_RCAR_CSI2=m
 CONFIG_VIDEO_RCAR_VIN=m
 CONFIG_VIDEO_SUN6I_CSI=m
@@ -643,7 +635,6 @@ CONFIG_SDR_PLATFORM_DRIVERS=y
 CONFIG_VIDEO_RCAR_DRIF=m
 CONFIG_VIDEO_IMX219=m
 CONFIG_VIDEO_OV5645=m
-CONFIG_VIDEO_QCOM_CAMSS=m
 CONFIG_DRM=m
 CONFIG_DRM_I2C_NXP_TDA998X=m
 CONFIG_DRM_MALI_DISPLAY=m
@@ -677,8 +668,8 @@ CONFIG_DRM_PANEL_RAYDIUM_RM67191=m
 CONFIG_DRM_PANEL_SITRONIX_ST7703=m
 CONFIG_DRM_PANEL_TRULY_NT35597_WQXGA=m
 CONFIG_DRM_DISPLAY_CONNECTOR=m
-CONFIG_DRM_NWL_MIPI_DSI=m
 CONFIG_DRM_LONTIUM_LT9611=m
+CONFIG_DRM_NWL_MIPI_DSI=m
 CONFIG_DRM_SII902X=m
 CONFIG_DRM_SIMPLE_BRIDGE=m
 CONFIG_DRM_THINE_THC63LVD1024=m
@@ -711,7 +702,6 @@ CONFIG_SND_HDA_TEGRA=m
 CONFIG_SND_HDA_CODEC_HDMI=m
 CONFIG_SND_SOC=y
 CONFIG_SND_BCM2835_SOC_I2S=m
-CONFIG_SND_SOC_FSL_SAI=m
 CONFIG_SND_SOC_FSL_ASRC=m
 CONFIG_SND_SOC_FSL_MICFIL=m
 CONFIG_SND_SOC_FSL_EASRC=m
@@ -750,7 +740,6 @@ CONFIG_SND_SOC_WSA881X=m
 CONFIG_SND_SIMPLE_CARD=m
 CONFIG_SND_AUDIO_GRAPH_CARD=m
 CONFIG_I2C_HID=m
-CONFIG_USB_CONN_GPIO=m
 CONFIG_USB=y
 CONFIG_USB_OTG=y
 CONFIG_USB_XHCI_HCD=y
@@ -887,14 +876,13 @@ CONFIG_VIRTIO_BALLOON=y
 CONFIG_VIRTIO_MMIO=y
 CONFIG_XEN_GNTDEV=y
 CONFIG_XEN_GRANT_DEV_ALLOC=y
-CONFIG_MFD_CROS_EC_DEV=y
 CONFIG_CHROME_PLATFORMS=y
 CONFIG_CROS_EC=y
 CONFIG_CROS_EC_I2C=y
 CONFIG_CROS_EC_SPI=y
 CONFIG_CROS_EC_CHARDEV=m
-CONFIG_COMMON_CLK_SCMI=y
 CONFIG_COMMON_CLK_RK808=y
+CONFIG_COMMON_CLK_SCMI=y
 CONFIG_COMMON_CLK_SCPI=y
 CONFIG_COMMON_CLK_CS2000_CP=y
 CONFIG_COMMON_CLK_FSL_SAI=y
@@ -914,8 +902,8 @@ CONFIG_QCOM_A53PLL=y
 CONFIG_QCOM_CLK_APCS_MSM8916=y
 CONFIG_QCOM_CLK_SMD_RPM=y
 CONFIG_QCOM_CLK_RPMH=y
-CONFIG_IPQ_GCC_8074=y
 CONFIG_IPQ_GCC_6018=y
+CONFIG_IPQ_GCC_8074=y
 CONFIG_MSM_GCC_8916=y
 CONFIG_MSM_GCC_8994=y
 CONFIG_MSM_MMCC_8996=y
@@ -923,12 +911,9 @@ CONFIG_MSM_GCC_8998=y
 CONFIG_QCS_GCC_404=y
 CONFIG_SC_GCC_7180=y
 CONFIG_SDM_CAMCC_845=m
-CONFIG_SDM_GCC_845=y
 CONFIG_SDM_GPUCC_845=y
 CONFIG_SDM_VIDEOCC_845=y
 CONFIG_SDM_DISPCC_845=y
-CONFIG_SM_GCC_8150=y
-CONFIG_SM_GCC_8250=y
 CONFIG_SM_GPUCC_8150=y
 CONFIG_SM_GPUCC_8250=y
 CONFIG_QCOM_HFPLL=y
@@ -960,6 +945,7 @@ CONFIG_FSL_DPAA=y
 CONFIG_FSL_MC_DPIO=y
 CONFIG_QCOM_AOSS_QMP=y
 CONFIG_QCOM_COMMAND_DB=y
+CONFIG_QCOM_CPR=y
 CONFIG_QCOM_GENI_SE=y
 CONFIG_QCOM_RMTFS_MEM=m
 CONFIG_QCOM_RPMH=y
@@ -971,28 +957,27 @@ CONFIG_QCOM_SMP2P=y
 CONFIG_QCOM_SMSM=y
 CONFIG_QCOM_SOCINFO=m
 CONFIG_QCOM_APR=m
-CONFIG_ARCH_R8A774A1=y
-CONFIG_ARCH_R8A774B1=y
-CONFIG_ARCH_R8A774C0=y
-CONFIG_ARCH_R8A774E1=y
+CONFIG_ARCH_R8A77995=y
+CONFIG_ARCH_R8A77990=y
 CONFIG_ARCH_R8A77950=y
 CONFIG_ARCH_R8A77951=y
+CONFIG_ARCH_R8A77965=y
 CONFIG_ARCH_R8A77960=y
 CONFIG_ARCH_R8A77961=y
-CONFIG_ARCH_R8A77965=y
-CONFIG_ARCH_R8A77970=y
 CONFIG_ARCH_R8A77980=y
-CONFIG_ARCH_R8A77990=y
-CONFIG_ARCH_R8A77995=y
+CONFIG_ARCH_R8A77970=y
 CONFIG_ARCH_R8A779A0=y
+CONFIG_ARCH_R8A774C0=y
+CONFIG_ARCH_R8A774E1=y
+CONFIG_ARCH_R8A774A1=y
+CONFIG_ARCH_R8A774B1=y
+CONFIG_ROCKCHIP_IODOMAIN=y
 CONFIG_ROCKCHIP_PM_DOMAINS=y
 CONFIG_ARCH_TEGRA_132_SOC=y
 CONFIG_ARCH_TEGRA_210_SOC=y
 CONFIG_ARCH_TEGRA_186_SOC=y
 CONFIG_ARCH_TEGRA_194_SOC=y
 CONFIG_ARCH_TEGRA_234_SOC=y
-CONFIG_ARCH_K3_AM6_SOC=y
-CONFIG_ARCH_K3_J721E_SOC=y
 CONFIG_TI_SCI_PM_DOMAINS=y
 CONFIG_EXTCON_PTN5150=m
 CONFIG_EXTCON_USB_GPIO=y
@@ -1052,9 +1037,9 @@ CONFIG_PHY_UNIPHIER_USB3=y
 CONFIG_PHY_TEGRA_XUSB=y
 CONFIG_ARM_SMMU_V3_PMU=m
 CONFIG_FSL_IMX8_DDR_PMU=m
-CONFIG_HISI_PMU=y
 CONFIG_QCOM_L2_PMU=y
 CONFIG_QCOM_L3_PMU=y
+CONFIG_HISI_PMU=y
 CONFIG_NVMEM_IMX_OCOTP=y
 CONFIG_NVMEM_IMX_OCOTP_SCU=y
 CONFIG_QCOM_QFPROM=y
@@ -1070,11 +1055,9 @@ CONFIG_FPGA_REGION=m
 CONFIG_OF_FPGA_REGION=m
 CONFIG_TEE=y
 CONFIG_OPTEE=y
-CONFIG_SLIMBUS=m
+CONFIG_MUX_MMIO=y
 CONFIG_SLIM_QCOM_CTRL=m
 CONFIG_SLIM_QCOM_NGD_CTRL=m
-CONFIG_MUX_MMIO=y
-CONFIG_INTERCONNECT=y
 CONFIG_INTERCONNECT_QCOM=y
 CONFIG_INTERCONNECT_QCOM_MSM8916=m
 CONFIG_INTERCONNECT_QCOM_OSM_L3=m
@@ -1095,7 +1078,6 @@ CONFIG_CUSE=m
 CONFIG_OVERLAY_FS=m
 CONFIG_VFAT_FS=y
 CONFIG_HUGETLBFS=y
-CONFIG_CONFIGFS_FS=y
 CONFIG_EFIVAR_FS=y
 CONFIG_SQUASHFS=y
 CONFIG_NFS_FS=y
diff --git a/drivers/bus/mhi/core/internal.h b/drivers/bus/mhi/core/internal.h
index 6f80ec3..005286b 100644
--- a/drivers/bus/mhi/core/internal.h
+++ b/drivers/bus/mhi/core/internal.h
@@ -643,6 +643,9 @@ int __must_check mhi_read_reg(struct mhi_controller *mhi_cntrl,
 int __must_check mhi_read_reg_field(struct mhi_controller *mhi_cntrl,
 				    void __iomem *base, u32 offset, u32 mask,
 				    u32 shift, u32 *out);
+int __must_check mhi_poll_reg_field(struct mhi_controller *mhi_cntrl,
+				    void __iomem *base, u32 offset, u32 mask,
+				    u32 shift, u32 val, u32 delayus);
 void mhi_write_reg(struct mhi_controller *mhi_cntrl, void __iomem *base,
 		   u32 offset, u32 val);
 void mhi_write_reg_field(struct mhi_controller *mhi_cntrl, void __iomem *base,
diff --git a/drivers/bus/mhi/core/main.c b/drivers/bus/mhi/core/main.c
index 4e0131b..249ae26 100644
--- a/drivers/bus/mhi/core/main.c
+++ b/drivers/bus/mhi/core/main.c
@@ -4,6 +4,7 @@
  *
  */
 
+#include <linux/delay.h>
 #include <linux/device.h>
 #include <linux/dma-direction.h>
 #include <linux/dma-mapping.h>
@@ -37,6 +38,28 @@ int __must_check mhi_read_reg_field(struct mhi_controller *mhi_cntrl,
 	return 0;
 }
 
+int __must_check mhi_poll_reg_field(struct mhi_controller *mhi_cntrl,
+				    void __iomem *base, u32 offset,
+				    u32 mask, u32 shift, u32 val, u32 delayus)
+{
+	int ret = -ENOENT;
+	u32 out, retry = (mhi_cntrl->timeout_ms * 1000) / delayus;
+
+	while (retry--) {
+		ret = mhi_read_reg_field(mhi_cntrl, base, offset, mask, shift,
+					 &out);
+		if (ret)
+			return -EIO;
+
+		if (out == val)
+			return 0;
+
+		udelay(delayus);
+	}
+
+	return ret;
+}
+
 void mhi_write_reg(struct mhi_controller *mhi_cntrl, void __iomem *base,
 		   u32 offset, u32 val)
 {
-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project

[PATCH v2 2/3] bus: mhi: core: Move to polling method to wait for MHI ready

[Bhaumik Bhatt]

In certain devices, it is likely that there is no incoming MHI
interrupt for a transition to MHI READY state. One such example
is the move from Pass Through to an SBL or AMSS execution
environment. In order to facilitate faster bootup times as there
is no need to wait until timeout_ms completes, MHI host can poll
every 25 milliseconds to check if device has entered MHI READY
until a maximum timeout of twice the timeout_ms is reached.

Signed-off-by: Bhaumik Bhatt <bbhatt@codeaurora.org>
---
 drivers/bus/mhi/core/pm.c | 31 ++++++++++++++-----------------
 1 file changed, 14 insertions(+), 17 deletions(-)

diff --git a/drivers/bus/mhi/core/pm.c b/drivers/bus/mhi/core/pm.c
index 681960c..5fe33d4 100644
--- a/drivers/bus/mhi/core/pm.c
+++ b/drivers/bus/mhi/core/pm.c
@@ -153,34 +153,31 @@ static void mhi_toggle_dev_wake(struct mhi_controller *mhi_cntrl)
 /* Handle device ready state transition */
 int mhi_ready_state_transition(struct mhi_controller *mhi_cntrl)
 {
-	void __iomem *base = mhi_cntrl->regs;
 	struct mhi_event *mhi_event;
 	enum mhi_pm_state cur_state;
 	struct device *dev = &mhi_cntrl->mhi_dev->dev;
-	u32 reset = 1, ready = 0;
 	int ret, i;
 
-	/* Wait for RESET to be cleared and READY bit to be set by the device */
-	wait_event_timeout(mhi_cntrl->state_event,
-			   MHI_PM_IN_FATAL_STATE(mhi_cntrl->pm_state) ||
-			   mhi_read_reg_field(mhi_cntrl, base, MHICTRL,
-					      MHICTRL_RESET_MASK,
-					      MHICTRL_RESET_SHIFT, &reset) ||
-			   mhi_read_reg_field(mhi_cntrl, base, MHISTATUS,
-					      MHISTATUS_READY_MASK,
-					      MHISTATUS_READY_SHIFT, &ready) ||
-			   (!reset && ready),
-			   msecs_to_jiffies(mhi_cntrl->timeout_ms));
-
 	/* Check if device entered error state */
 	if (MHI_PM_IN_FATAL_STATE(mhi_cntrl->pm_state)) {
 		dev_err(dev, "Device link is not accessible\n");
 		return -EIO;
 	}
 
-	/* Timeout if device did not transition to ready state */
-	if (reset || !ready) {
-		dev_err(dev, "Device Ready timeout\n");
+	/* Wait for RESET to be cleared and READY bit to be set by the device */
+	ret = mhi_poll_reg_field(mhi_cntrl, mhi_cntrl->regs, MHICTRL,
+				 MHICTRL_RESET_MASK, MHICTRL_RESET_SHIFT, 0,
+				 25000);
+	if (ret) {
+		dev_err(dev, "Device failed to clear MHI Reset\n");
+		return -ETIMEDOUT;
+	}
+
+	ret = mhi_poll_reg_field(mhi_cntrl, mhi_cntrl->regs, MHISTATUS,
+				 MHISTATUS_READY_MASK, MHISTATUS_READY_SHIFT, 1,
+				 25000);
+	if (ret) {
+		dev_err(dev, "Device failed to enter MHI Ready\n");
 		return -ETIMEDOUT;
 	}
 
-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project

[PATCH v2 3/3] bus: mhi: core: Use poll register read API for RDDM download

[Bhaumik Bhatt]

Make use of mhi_poll_reg_field() API in order to poll for RDDM
download in panic path to employ a common approach throughout the
driver.

Signed-off-by: Bhaumik Bhatt <bbhatt@codeaurora.org>
---
 drivers/bus/mhi/core/boot.c | 20 ++++++--------------
 1 file changed, 6 insertions(+), 14 deletions(-)

diff --git a/drivers/bus/mhi/core/boot.c b/drivers/bus/mhi/core/boot.c
index c2546bf..b9c44e0 100644
--- a/drivers/bus/mhi/core/boot.c
+++ b/drivers/bus/mhi/core/boot.c
@@ -60,7 +60,6 @@ static int __mhi_download_rddm_in_panic(struct mhi_controller *mhi_cntrl)
 	u32 rx_status;
 	enum mhi_ee_type ee;
 	const u32 delayus = 2000;
-	u32 retry = (mhi_cntrl->timeout_ms * 1000) / delayus;
 	const u32 rddm_timeout_us = 200000;
 	int rddm_retry = rddm_timeout_us / delayus;
 	void __iomem *base = mhi_cntrl->bhie;
@@ -125,19 +124,12 @@ static int __mhi_download_rddm_in_panic(struct mhi_controller *mhi_cntrl)
 		"Waiting for RDDM image download via BHIe, current EE:%s\n",
 		TO_MHI_EXEC_STR(ee));
 
-	while (retry--) {
-		ret = mhi_read_reg_field(mhi_cntrl, base, BHIE_RXVECSTATUS_OFFS,
-					 BHIE_RXVECSTATUS_STATUS_BMSK,
-					 BHIE_RXVECSTATUS_STATUS_SHFT,
-					 &rx_status);
-		if (ret)
-			return -EIO;
-
-		if (rx_status == BHIE_RXVECSTATUS_STATUS_XFER_COMPL)
-			return 0;
-
-		udelay(delayus);
-	}
+	ret = mhi_poll_reg_field(mhi_cntrl, base, BHIE_RXVECSTATUS_OFFS,
+				 BHIE_RXVECSTATUS_STATUS_BMSK,
+				 BHIE_RXVECSTATUS_STATUS_SHFT,
+				 BHIE_RXVECSTATUS_STATUS_XFER_COMPL, delayus);
+	if (!ret)
+		return 0;
 
 	ee = mhi_get_exec_env(mhi_cntrl);
 	ret = mhi_read_reg(mhi_cntrl, base, BHIE_RXVECSTATUS_OFFS, &rx_status);
-- 
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