[PATCH v2 1/2] firmware: qcom: scm: Introduce CP_SMMU_APERTURE_ID

[Bjorn Andersson]

The QCOM_SCM_SVC_MP service provides QCOM_SCM_MP_CP_SMMU_APERTURE_ID,
which is used to trigger the mapping of register banks into the SMMU
context for per-processes page tables to function (in case this isn't
statically setup by firmware).

This is necessary on e.g. QCS6490 Rb3Gen2, in order to avoid "CP | AHB
bus error"-errors from the GPU.

Introduce a function to allow the msm driver to invoke this call.

Signed-off-by: Bjorn Andersson <bjorn.andersson at oss.qualcomm.com>
---
 drivers/firmware/qcom/qcom_scm.c       | 26 ++++++++++++++++++++++++++
 drivers/firmware/qcom/qcom_scm.h       |  1 +
 include/linux/firmware/qcom/qcom_scm.h |  2 ++
 3 files changed, 29 insertions(+)

diff --git a/drivers/firmware/qcom/qcom_scm.c b/drivers/firmware/qcom/qcom_scm.c
index 95815e64e1e6..72bf87ddcd96 100644
--- a/drivers/firmware/qcom/qcom_scm.c
+++ b/drivers/firmware/qcom/qcom_scm.c
@@ -904,6 +904,32 @@ int qcom_scm_restore_sec_cfg(u32 device_id, u32 spare)
 }
 EXPORT_SYMBOL_GPL(qcom_scm_restore_sec_cfg);
 
+#define QCOM_SCM_CP_APERTURE_CONTEXT_MASK	GENMASK(7, 0)
+
+bool qcom_scm_set_gpu_smmu_aperture_is_available(void)
+{
+	return __qcom_scm_is_call_available(__scm->dev, QCOM_SCM_SVC_MP,
+					    QCOM_SCM_MP_CP_SMMU_APERTURE_ID);
+}
+EXPORT_SYMBOL_GPL(qcom_scm_set_gpu_smmu_aperture_is_available);
+
+int qcom_scm_set_gpu_smmu_aperture(unsigned int context_bank)
+{
+	struct qcom_scm_desc desc = {
+		.svc = QCOM_SCM_SVC_MP,
+		.cmd = QCOM_SCM_MP_CP_SMMU_APERTURE_ID,
+		.arginfo = QCOM_SCM_ARGS(4),
+		.args[0] = 0xffff0000 | FIELD_PREP(QCOM_SCM_CP_APERTURE_CONTEXT_MASK, context_bank),
+		.args[1] = 0xffffffff,
+		.args[2] = 0xffffffff,
+		.args[3] = 0xffffffff,
+		.owner = ARM_SMCCC_OWNER_SIP
+	};
+
+	return qcom_scm_call(__scm->dev, &desc, NULL);
+}
+EXPORT_SYMBOL_GPL(qcom_scm_set_gpu_smmu_aperture);
+
 int qcom_scm_iommu_secure_ptbl_size(u32 spare, size_t *size)
 {
 	struct qcom_scm_desc desc = {
diff --git a/drivers/firmware/qcom/qcom_scm.h b/drivers/firmware/qcom/qcom_scm.h
index 685b8f59e7a6..e36b2f67607f 100644
--- a/drivers/firmware/qcom/qcom_scm.h
+++ b/drivers/firmware/qcom/qcom_scm.h
@@ -116,6 +116,7 @@ struct qcom_tzmem_pool *qcom_scm_get_tzmem_pool(void);
 #define QCOM_SCM_MP_IOMMU_SET_CP_POOL_SIZE	0x05
 #define QCOM_SCM_MP_VIDEO_VAR			0x08
 #define QCOM_SCM_MP_ASSIGN			0x16
+#define QCOM_SCM_MP_CP_SMMU_APERTURE_ID		0x1b
 #define QCOM_SCM_MP_SHM_BRIDGE_ENABLE		0x1c
 #define QCOM_SCM_MP_SHM_BRIDGE_DELETE		0x1d
 #define QCOM_SCM_MP_SHM_BRIDGE_CREATE		0x1e
diff --git a/include/linux/firmware/qcom/qcom_scm.h b/include/linux/firmware/qcom/qcom_scm.h
index 9f14976399ab..4621aec0328c 100644
--- a/include/linux/firmware/qcom/qcom_scm.h
+++ b/include/linux/firmware/qcom/qcom_scm.h
@@ -85,6 +85,8 @@ int qcom_scm_io_writel(phys_addr_t addr, unsigned int val);
 
 bool qcom_scm_restore_sec_cfg_available(void);
 int qcom_scm_restore_sec_cfg(u32 device_id, u32 spare);
+int qcom_scm_set_gpu_smmu_aperture(unsigned int context_bank);
+bool qcom_scm_set_gpu_smmu_aperture_is_available(void);
 int qcom_scm_iommu_secure_ptbl_size(u32 spare, size_t *size);
 int qcom_scm_iommu_secure_ptbl_init(u64 addr, u32 size, u32 spare);
 int qcom_scm_iommu_set_cp_pool_size(u32 spare, u32 size);

-- 
2.45.2