[PATCH v9 09/14] media: iris: Handle CPU_CS_SCIACMDARG3 register write via program bootup registers hook

From: Vishnu Reddy

Date: Wed Jul 15 2026 - 10:23:00 EST


On the Glymur platform, the firmware reads CPU_CS_SCIACMDARG3 during boot
to determine the VM count and increments it by 1. Writing the default 0x1
causes the firmware to treat the VM count as 2. To avoid that write 0x0 to
CPU_CS_SCIACMDARG3 as a Glymur platform specific.

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxxxxxxxx>
Signed-off-by: Vishnu Reddy <busanna.reddy@xxxxxxxxxxxxxxxx>
---
drivers/media/platform/qcom/iris/iris_vpu3x.c | 6 ++++++
drivers/media/platform/qcom/iris/iris_vpu_common.c | 4 ++--
drivers/media/platform/qcom/iris/iris_vpu_register_defines.h | 1 +
3 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/media/platform/qcom/iris/iris_vpu3x.c b/drivers/media/platform/qcom/iris/iris_vpu3x.c
index 4894cba62677..7d5007abaded 100644
--- a/drivers/media/platform/qcom/iris/iris_vpu3x.c
+++ b/drivers/media/platform/qcom/iris/iris_vpu3x.c
@@ -333,6 +333,11 @@ static int iris_vpu36_set_hwmode(struct iris_core *core)
return ret;
}

+static void iris_vpu36_program_bootup_registers(struct iris_core *core)
+{
+ writel(0x0, core->reg_base + CPU_CS_SCIACMDARG3);
+}
+
const struct vpu_ops iris_vpu3_ops = {
.power_off_hw = iris_vpu3_power_off_hardware,
.power_on_hw = iris_vpu_power_on_hw,
@@ -366,6 +371,7 @@ const struct vpu_ops iris_vpu36_ops = {
.power_on_hw = iris_vpu36_power_on_hw,
.power_off_controller = iris_vpu35_vpu4x_power_off_controller,
.power_on_controller = iris_vpu35_vpu4x_power_on_controller,
+ .program_bootup_registers = iris_vpu36_program_bootup_registers,
.calc_freq = iris_vpu3x_vpu4x_calculate_frequency,
.set_hwmode = iris_vpu36_set_hwmode,
};
diff --git a/drivers/media/platform/qcom/iris/iris_vpu_common.c b/drivers/media/platform/qcom/iris/iris_vpu_common.c
index e690c566c875..72eb8f6240b7 100644
--- a/drivers/media/platform/qcom/iris/iris_vpu_common.c
+++ b/drivers/media/platform/qcom/iris/iris_vpu_common.c
@@ -26,7 +26,6 @@
#define QTBL_ENABLE BIT(0)

#define QTBL_ADDR (CPU_CS_BASE_OFFS + 0x54)
-#define CPU_CS_SCIACMDARG3 (CPU_CS_BASE_OFFS + 0x58)
#define SFR_ADDR (CPU_CS_BASE_OFFS + 0x5C)
#define UC_REGION_ADDR (CPU_CS_BASE_OFFS + 0x64)
#define UC_REGION_SIZE (CPU_CS_BASE_OFFS + 0x68)
@@ -67,6 +66,8 @@ static void iris_vpu_setup_ucregion_memory_map(struct iris_core *core)
writel(value, core->reg_base + SFR_ADDR);
}

+ writel(0x1, core->reg_base + CPU_CS_SCIACMDARG3);
+
if (vpu_ops->program_bootup_registers)
vpu_ops->program_bootup_registers(core);
}
@@ -78,7 +79,6 @@ int iris_vpu_boot_firmware(struct iris_core *core)
iris_vpu_setup_ucregion_memory_map(core);

writel(ctrl_init, core->reg_base + CTRL_INIT);
- writel(0x1, core->reg_base + CPU_CS_SCIACMDARG3);

while (!ctrl_status && count < max_tries) {
ctrl_status = readl(core->reg_base + CTRL_STATUS);
diff --git a/drivers/media/platform/qcom/iris/iris_vpu_register_defines.h b/drivers/media/platform/qcom/iris/iris_vpu_register_defines.h
index c44c85eac3b5..3782454b7d06 100644
--- a/drivers/media/platform/qcom/iris/iris_vpu_register_defines.h
+++ b/drivers/media/platform/qcom/iris/iris_vpu_register_defines.h
@@ -29,6 +29,7 @@
#define CPU_CS_A2HSOFTINTCLR (CPU_CS_BASE_OFFS + 0x1C)
#define CLEAR_XTENSA2HOST_INTR BIT(0)

+#define CPU_CS_SCIACMDARG3 (CPU_CS_BASE_OFFS + 0x58)
#define CPU_CS_H2XSOFTINTEN (CPU_CS_BASE_OFFS + 0x148)
#define HOST2XTENSA_INTR_ENABLE BIT(0)


--
2.34.1