scsi: ufs: ufs-qcom: Streamline UFS MCQ resource mapping

The current MCQ resource configuration involves multiple resource
mappings and dynamic resource allocation.

Simplify the resource mapping by directly mapping the single "mcq"
resource from device tree to hba->mcq_base instead of mapping multiple
separate resources (RES_UFS, RES_MCQ, RES_MCQ_SQD, RES_MCQ_VS).

It also uses predefined offsets for MCQ doorbell registers (SQD, CQD,
SQIS, CQIS) relative to the MCQ base,providing clearer memory layout
clarity.

Additionally update vendor-specific register offset UFS_MEM_CQIS_VS
offset from 0x8 to 0x4008 to align with the hardware programming guide.

The new approach assumes the device tree provides a single "mcq"
resource that encompasses the entire MCQ configuration space, making the
driver more maintainable and less prone to resource mapping errors.

The change aligns the driver implementation with the device tree binding
specification, which defines a single 'mcq' memory region rather than
multiple separate regions.

Co-developed-by: Ram Kumar Dwivedi <[e-mail]>
Signed-off-by: Ram Kumar Dwivedi <[e-mail]>
Signed-off-by: Nitin Rawat <[e-mail]>
Reviewed-by: Manivannan Sadhasivam <[e-mail]>
Signed-off-by: Martin K. Petersen <[e-mail]>

drivers/ufs/host/ufs-qcom.c

···
 	hba->clk_scaling.suspend_on_no_request = true;
 }
 
-/* Resources */
-static const struct ufshcd_res_info ufs_res_info[RES_MAX] = {
-	{.name = "ufs_mem",},
-	{.name = "mcq",},
-	/* Submission Queue DAO */
-	{.name = "mcq_sqd",},
-	/* Submission Queue Interrupt Status */
-	{.name = "mcq_sqis",},
-	/* Completion Queue DAO */
-	{.name = "mcq_cqd",},
-	/* Completion Queue Interrupt Status */
-	{.name = "mcq_cqis",},
-	/* MCQ vendor specific */
-	{.name = "mcq_vs",},
-};
-
 static int ufs_qcom_mcq_config_resource(struct ufs_hba *hba)
 {
 	struct platform_device *pdev = to_platform_device(hba->dev);
-	struct ufshcd_res_info *res;
-	struct resource *res_mem, *res_mcq;
-	int i, ret;
+	struct resource *res;
 
-	memcpy(hba->res, ufs_res_info, sizeof(ufs_res_info));
-
-	for (i = 0; i < RES_MAX; i++) {
-		res = &hba->res[i];
-		res->resource = platform_get_resource_byname(pdev,
-							     IORESOURCE_MEM,
-							     res->name);
-		if (!res->resource) {
-			dev_info(hba->dev, "Resource %s not provided\n", res->name);
-			if (i == RES_UFS)
-				return -ENODEV;
-			continue;
-		} else if (i == RES_UFS) {
-			res_mem = res->resource;
-			res->base = hba->mmio_base;
-			continue;
-		}
-
-		res->base = devm_ioremap_resource(hba->dev, res->resource);
-		if (IS_ERR(res->base)) {
-			dev_err(hba->dev, "Failed to map res %s, err=%d\n",
-					 res->name, (int)PTR_ERR(res->base));
-			ret = PTR_ERR(res->base);
-			res->base = NULL;
-			return ret;
-		}
+	/* Map the MCQ configuration region */
+	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "mcq");
+	if (!res) {
+		dev_err(hba->dev, "MCQ resource not found in device tree\n");
+		return -ENODEV;
 	}
 
-	/* MCQ resource provided in DT */
-	res = &hba->res[RES_MCQ];
-	/* Bail if MCQ resource is provided */
-	if (res->base)
-		goto out;
-
-	/* Explicitly allocate MCQ resource from ufs_mem */
-	res_mcq = devm_kzalloc(hba->dev, sizeof(*res_mcq), GFP_KERNEL);
-	if (!res_mcq)
-		return -ENOMEM;
-
-	res_mcq->start = res_mem->start +
-			 MCQ_SQATTR_OFFSET(hba->mcq_capabilities);
-	res_mcq->end = res_mcq->start + hba->nr_hw_queues * MCQ_QCFG_SIZE - 1;
-	res_mcq->flags = res_mem->flags;
-	res_mcq->name = "mcq";
-
-	ret = insert_resource(&iomem_resource, res_mcq);
-	if (ret) {
-		dev_err(hba->dev, "Failed to insert MCQ resource, err=%d\n",
-			ret);
-		return ret;
+	hba->mcq_base = devm_ioremap_resource(hba->dev, res);
+	if (IS_ERR(hba->mcq_base)) {
+		dev_err(hba->dev, "Failed to map MCQ region: %ld\n",
+			PTR_ERR(hba->mcq_base));
+		return PTR_ERR(hba->mcq_base);
 	}
 
-	res->base = devm_ioremap_resource(hba->dev, res_mcq);
-	if (IS_ERR(res->base)) {
-		dev_err(hba->dev, "MCQ registers mapping failed, err=%d\n",
-			(int)PTR_ERR(res->base));
-		ret = PTR_ERR(res->base);
-		goto ioremap_err;
-	}
-
-out:
-	hba->mcq_base = res->base;
 	return 0;
-ioremap_err:
-	res->base = NULL;
-	remove_resource(res_mcq);
-	return ret;
 }
 
 static int ufs_qcom_op_runtime_config(struct ufs_hba *hba)
 {
-	struct ufshcd_res_info *mem_res, *sqdao_res;
 	struct ufshcd_mcq_opr_info_t *opr;
 	int i;
+	u32 doorbell_offsets[OPR_MAX];
 
-	mem_res = &hba->res[RES_UFS];
-	sqdao_res = &hba->res[RES_MCQ_SQD];
+	/*
+	 * Configure doorbell address offsets in MCQ configuration registers.
+	 * These values are offsets relative to mmio_base (UFS_HCI_BASE).
+	 *
+	 * Memory Layout:
+	 * - mmio_base = UFS_HCI_BASE
+	 * - mcq_base  = MCQ_CONFIG_BASE = mmio_base + (UFS_QCOM_MCQCAP_QCFGPTR * 0x200)
+	 * - Doorbell registers are at: mmio_base + (UFS_QCOM_MCQCAP_QCFGPTR * 0x200) +
+	 * -				UFS_QCOM_MCQ_SQD_OFFSET
+	 * - Which is also: mcq_base +  UFS_QCOM_MCQ_SQD_OFFSET
+	 */
 
-	if (!mem_res->base || !sqdao_res->base)
-		return -EINVAL;
+	doorbell_offsets[OPR_SQD] = UFS_QCOM_SQD_ADDR_OFFSET;
+	doorbell_offsets[OPR_SQIS] = UFS_QCOM_SQIS_ADDR_OFFSET;
+	doorbell_offsets[OPR_CQD] = UFS_QCOM_CQD_ADDR_OFFSET;
+	doorbell_offsets[OPR_CQIS] = UFS_QCOM_CQIS_ADDR_OFFSET;
 
+	/*
+	 * Configure MCQ operation registers.
+	 *
+	 * The doorbell registers are physically located within the MCQ region:
+	 * - doorbell_physical_addr = mmio_base + doorbell_offset
+	 * - doorbell_physical_addr = mcq_base + (doorbell_offset - MCQ_CONFIG_OFFSET)
+	 */
 	for (i = 0; i < OPR_MAX; i++) {
 		opr = &hba->mcq_opr[i];
-		opr->offset = sqdao_res->resource->start -
-			      mem_res->resource->start + 0x40 * i;
-		opr->stride = 0x100;
-		opr->base = sqdao_res->base + 0x40 * i;
+		opr->offset = doorbell_offsets[i];  /* Offset relative to mmio_base */
+		opr->stride = UFS_QCOM_MCQ_STRIDE;  /* 256 bytes between queues */
+
+		/*
+		 * Calculate the actual doorbell base address within MCQ region:
+		 * base = mcq_base + (doorbell_offset - MCQ_CONFIG_OFFSET)
+		 */
+		opr->base = hba->mcq_base + (opr->offset - UFS_QCOM_MCQ_CONFIG_OFFSET);
 	}
 
 	return 0;
···
 static int ufs_qcom_get_outstanding_cqs(struct ufs_hba *hba,
 					unsigned long *ocqs)
 {
-	struct ufshcd_res_info *mcq_vs_res = &hba->res[RES_MCQ_VS];
-
-	if (!mcq_vs_res->base)
-		return -EINVAL;
-
-	*ocqs = readl(mcq_vs_res->base + UFS_MEM_CQIS_VS);
+	/* Read from MCQ vendor-specific register in MCQ region */
+	*ocqs = readl(hba->mcq_base + UFS_MEM_CQIS_VS);
 
 	return 0;
 }

drivers/ufs/host/ufs-qcom.h

···
 #define DL_VS_CLK_CFG_MASK GENMASK(9, 0)
 #define DME_VS_CORE_CLK_CTRL_DME_HW_CGC_EN             BIT(9)
 
+/* Qualcomm MCQ Configuration */
+#define UFS_QCOM_MCQCAP_QCFGPTR     224  /* 0xE0 in hex */
+#define UFS_QCOM_MCQ_CONFIG_OFFSET  (UFS_QCOM_MCQCAP_QCFGPTR * 0x200)  /* 0x1C000 */
+
+/* Doorbell offsets within MCQ region (relative to MCQ_CONFIG_BASE) */
+#define UFS_QCOM_MCQ_SQD_OFFSET     0x5000
+#define UFS_QCOM_MCQ_CQD_OFFSET     0x5080
+#define UFS_QCOM_MCQ_SQIS_OFFSET    0x5040
+#define UFS_QCOM_MCQ_CQIS_OFFSET    0x50C0
+#define UFS_QCOM_MCQ_STRIDE         0x100
+
+/* Calculated doorbell address offsets (relative to mmio_base) */
+#define UFS_QCOM_SQD_ADDR_OFFSET    (UFS_QCOM_MCQ_CONFIG_OFFSET + UFS_QCOM_MCQ_SQD_OFFSET)
+#define UFS_QCOM_CQD_ADDR_OFFSET    (UFS_QCOM_MCQ_CONFIG_OFFSET + UFS_QCOM_MCQ_CQD_OFFSET)
+#define UFS_QCOM_SQIS_ADDR_OFFSET   (UFS_QCOM_MCQ_CONFIG_OFFSET + UFS_QCOM_MCQ_SQIS_OFFSET)
+#define UFS_QCOM_CQIS_ADDR_OFFSET   (UFS_QCOM_MCQ_CONFIG_OFFSET + UFS_QCOM_MCQ_CQIS_OFFSET)
+#define REG_UFS_MCQ_STRIDE          UFS_QCOM_MCQ_STRIDE
+
+/* MCQ Vendor specific address offsets (relative to MCQ_CONFIG_BASE) */
+#define UFS_MEM_VS_BASE 0x4000
+#define UFS_MEM_CQIS_VS 0x4008
+
 /* QCOM UFS host controller vendor specific registers */
 enum {
 	REG_UFS_SYS1CLK_1US                 = 0xC0,
···
 	REG_UFS_SW_AFTER_HW_H8_ENTER_CNT	= 0x2708,
 	REG_UFS_HW_H8_EXIT_CNT			= 0x270C,
 	REG_UFS_SW_H8_EXIT_CNT			= 0x2710,
-};
-
-enum {
-	UFS_MEM_CQIS_VS		= 0x8,
 };
 
 #define UFS_CNTLR_2_x_x_VEN_REGS_OFFSET(x)	(0x000 + x)