firmware: qcom: scm: Add function to set the maximum IOMMU pool size

This is not necessary for basic functionality of the IOMMU, but
it's an optimization that tells to the TZ what's the maximum
mappable size for the secure IOMMUs, so that it can optimize
the data structures in the TZ itself.
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@somainline.org>
[Marijn: ported from 5.3 to the unified architecture in 5.11]
Signed-off-by: Marijn Suijten <marijn.suijten@somainline.org>
Reviewed-by: Konrad Dybcio <konrad.dybcio@somainline.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20211208083423.22037-3-marijn.suijten@somainline.org

drivers/firmware/qcom_scm.c

@@ -759,6 +759,21 @@ int qcom_scm_iommu_secure_ptbl_init(u64 addr, u32 size, u32 spare)
 }
 EXPORT_SYMBOL(qcom_scm_iommu_secure_ptbl_init);
 
+int qcom_scm_iommu_set_cp_pool_size(u32 spare, u32 size)
+{
+	struct qcom_scm_desc desc = {
+		.svc = QCOM_SCM_SVC_MP,
+		.cmd = QCOM_SCM_MP_IOMMU_SET_CP_POOL_SIZE,
+		.arginfo = QCOM_SCM_ARGS(2),
+		.args[0] = size,
+		.args[1] = spare,
+		.owner = ARM_SMCCC_OWNER_SIP,
+	};
+
+	return qcom_scm_call(__scm->dev, &desc, NULL);
+}
+EXPORT_SYMBOL(qcom_scm_iommu_set_cp_pool_size);
+
 int qcom_scm_mem_protect_video_var(u32 cp_start, u32 cp_size,
 				   u32 cp_nonpixel_start,
 				   u32 cp_nonpixel_size)

drivers/firmware/qcom_scm.h

@@ -100,6 +100,7 @@ extern int scm_legacy_call(struct device *dev, const struct qcom_scm_desc *desc,
 #define QCOM_SCM_MP_RESTORE_SEC_CFG		0x02
 #define QCOM_SCM_MP_IOMMU_SECURE_PTBL_SIZE	0x03
 #define QCOM_SCM_MP_IOMMU_SECURE_PTBL_INIT	0x04
+#define QCOM_SCM_MP_IOMMU_SET_CP_POOL_SIZE	0x05
 #define QCOM_SCM_MP_VIDEO_VAR			0x08
 #define QCOM_SCM_MP_ASSIGN			0x16
 

include/linux/qcom_scm.h

@@ -83,6 +83,7 @@ extern bool qcom_scm_restore_sec_cfg_available(void);
 extern int qcom_scm_restore_sec_cfg(u32 device_id, u32 spare);
 extern int qcom_scm_iommu_secure_ptbl_size(u32 spare, size_t *size);
 extern int qcom_scm_iommu_secure_ptbl_init(u64 addr, u32 size, u32 spare);
+extern int qcom_scm_iommu_set_cp_pool_size(u32 spare, u32 size);
 extern int qcom_scm_mem_protect_video_var(u32 cp_start, u32 cp_size,
 					  u32 cp_nonpixel_start,
 					  u32 cp_nonpixel_size);