firmware: qcom_scm-64: Move SMC register filling to qcom_scm_call_smccc

qcom_scm_call_smccc should be responsible for converting qcom_scm_desc
into arguments for smc call. Consolidate the dispersed logic to convert
qcom_scm_desc into smc arguments inside qcom_scm_call_smccc.

Tested-by: Brian Masney <masneyb@onstation.org> # arm32
Tested-by: Stephan Gerhold <stephan@gerhold.net>
Signed-off-by: Elliot Berman <eberman@codeaurora.org>
Link: https://lore.kernel.org/r/1578431066-19600-8-git-send-email-eberman@codeaurora.orgSigned-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>

drivers/firmware/qcom_scm-64.c

@@ -62,6 +62,14 @@ struct qcom_scm_res {
 	u64 result[MAX_QCOM_SCM_RETS];
 };
 
+/**
+ * struct arm_smccc_args
+ * @args:	The array of values used in registers in smc instruction
+ */
+struct arm_smccc_args {
+	unsigned long args[8];
+};
+
 static u64 qcom_smccc_convention = -1;
 static DEFINE_MUTEX(qcom_scm_lock);
 
@@ -71,46 +79,42 @@ static DEFINE_MUTEX(qcom_scm_lock);
 #define SCM_SMC_N_REG_ARGS	4
 #define SCM_SMC_FIRST_EXT_IDX	(SCM_SMC_N_REG_ARGS - 1)
 #define SCM_SMC_N_EXT_ARGS	(MAX_QCOM_SCM_ARGS - SCM_SMC_N_REG_ARGS + 1)
+#define SCM_SMC_FIRST_REG_IDX	2
+#define SCM_SMC_LAST_REG_IDX	(SCM_SMC_FIRST_REG_IDX + SCM_SMC_N_REG_ARGS - 1)
 
-static void __scm_smc_do_quirk(const struct qcom_scm_desc *desc,
-			       struct arm_smccc_res *res, u64 x5, u32 type)
+static void __scm_smc_do_quirk(const struct arm_smccc_args *smc,
+			       struct arm_smccc_res *res)
 {
-	u64 cmd;
+	unsigned long a0 = smc->args[0];
 	struct arm_smccc_quirk quirk = { .id = ARM_SMCCC_QUIRK_QCOM_A6 };
 
-	cmd = ARM_SMCCC_CALL_VAL(
-		type,
-		qcom_smccc_convention,
-		desc->owner,
-		SCM_SMC_FNID(desc->svc, desc->cmd));
-
 	quirk.state.a6 = 0;
 
 	do {
-		arm_smccc_smc_quirk(cmd, desc->arginfo, desc->args[0],
-				    desc->args[1], desc->args[2], x5,
-				    quirk.state.a6, 0, res, &quirk);
+		arm_smccc_smc_quirk(a0, smc->args[1], smc->args[2],
+				    smc->args[3], smc->args[4], smc->args[5],
+				    quirk.state.a6, smc->args[7], res, &quirk);
 
 		if (res->a0 == QCOM_SCM_INTERRUPTED)
-			cmd = res->a0;
+			a0 = res->a0;
 
 	} while (res->a0 == QCOM_SCM_INTERRUPTED);
 }
 
-static void __scm_smc_do(const struct qcom_scm_desc *desc,
-			 struct arm_smccc_res *res, u64 x5, bool atomic)
+static void __scm_smc_do(const struct arm_smccc_args *smc,
+			 struct arm_smccc_res *res, bool atomic)
 {
 	int retry_count = 0;
 
 	if (atomic) {
-		__scm_smc_do_quirk(desc, res, x5, ARM_SMCCC_FAST_CALL);
+		__scm_smc_do_quirk(smc, res);
 		return;
 	}
 
 	do {
 		mutex_lock(&qcom_scm_lock);
 
-		__scm_smc_do_quirk(desc, res, x5, ARM_SMCCC_STD_CALL);
+		__scm_smc_do_quirk(smc, res);
 
 		mutex_unlock(&qcom_scm_lock);
 
@@ -127,12 +131,22 @@ static int __scm_smc_call(struct device *dev, const struct qcom_scm_desc *desc,
 {
 	int arglen = desc->arginfo & 0xf;
 	int i;
-	u64 x5 = desc->args[SCM_SMC_FIRST_EXT_IDX];
 	dma_addr_t args_phys = 0;
 	void *args_virt = NULL;
 	size_t alloc_len;
 	gfp_t flag = atomic ? GFP_ATOMIC : GFP_KERNEL;
+	u32 smccc_call_type = atomic ? ARM_SMCCC_FAST_CALL : ARM_SMCCC_STD_CALL;
 	struct arm_smccc_res smc_res;
+	struct arm_smccc_args smc = {0};
+
+	smc.args[0] = ARM_SMCCC_CALL_VAL(
+		smccc_call_type,
+		qcom_smccc_convention,
+		desc->owner,
+		SCM_SMC_FNID(desc->svc, desc->cmd));
+	smc.args[1] = desc->arginfo;
+	for (i = 0; i < SCM_SMC_N_REG_ARGS; i++)
+		smc.args[i + SCM_SMC_FIRST_REG_IDX] = desc->args[i];
 
 	if (unlikely(arglen > SCM_SMC_N_REG_ARGS)) {
 		alloc_len = SCM_SMC_N_EXT_ARGS * sizeof(u64);
@@ -163,10 +177,10 @@ static int __scm_smc_call(struct device *dev, const struct qcom_scm_desc *desc,
 			return -ENOMEM;
 		}
 
-		x5 = args_phys;
+		smc.args[SCM_SMC_LAST_REG_IDX] = args_phys;
 	}
 
-	__scm_smc_do(desc, &smc_res, x5, atomic);
+	__scm_smc_do(&smc, &smc_res, atomic);
 
 	if (args_virt) {
 		dma_unmap_single(dev, args_phys, alloc_len, DMA_TO_DEVICE);