scsi: cxlflash: MMIO map the AFU

When the AFU is configured, the global and per process MMIO regions are
presented by the configuration space. Save these regions and map the global
MMIO region that is used to access all of the control and provisioning data in
the AFU.
Signed-off-by: NUma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: NMatthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: NFrederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/cxlflash/ocxl_hw.c

@@ -263,6 +263,18 @@ static void ocxlflash_perst_reloads_same_image(void *afu_cookie, bool image)
 	afu->perst_same_image = image;
 }
 
+/**
+ * ocxlflash_unconfig_afu() - unconfigure the AFU
+ * @afu: AFU associated with the host.
+ */
+static void ocxlflash_unconfig_afu(struct ocxl_hw_afu *afu)
+{
+	if (afu->gmmio_virt) {
+		iounmap(afu->gmmio_virt);
+		afu->gmmio_virt = NULL;
+	}
+}
+
 /**
  * ocxlflash_destroy_afu() - destroy the AFU structure
  * @afu_cookie:	AFU to be freed.
@@ -276,6 +288,7 @@ static void ocxlflash_destroy_afu(void *afu_cookie)
 
 	ocxlflash_release_context(afu->ocxl_ctx);
 	idr_destroy(&afu->idr);
+	ocxlflash_unconfig_afu(afu);
 	kfree(afu);
 }
 
@@ -326,6 +339,56 @@ static int ocxlflash_config_fn(struct pci_dev *pdev, struct ocxl_hw_afu *afu)
 	return rc;
 }
 
+/**
+ * ocxlflash_map_mmio() - map the AFU MMIO space
+ * @afu: AFU associated with the host.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int ocxlflash_map_mmio(struct ocxl_hw_afu *afu)
+{
+	struct ocxl_afu_config *acfg = &afu->acfg;
+	struct pci_dev *pdev = afu->pdev;
+	struct device *dev = afu->dev;
+	phys_addr_t gmmio, ppmmio;
+	int rc = 0;
+
+	rc = pci_request_region(pdev, acfg->global_mmio_bar, "ocxlflash");
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: pci_request_region for global failed rc=%d\n",
+			__func__, rc);
+		goto out;
+	}
+	gmmio = pci_resource_start(pdev, acfg->global_mmio_bar);
+	gmmio += acfg->global_mmio_offset;
+
+	rc = pci_request_region(pdev, acfg->pp_mmio_bar, "ocxlflash");
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: pci_request_region for pp bar failed rc=%d\n",
+			__func__, rc);
+		goto err1;
+	}
+	ppmmio = pci_resource_start(pdev, acfg->pp_mmio_bar);
+	ppmmio += acfg->pp_mmio_offset;
+
+	afu->gmmio_virt = ioremap(gmmio, acfg->global_mmio_size);
+	if (unlikely(!afu->gmmio_virt)) {
+		dev_err(dev, "%s: MMIO mapping failed\n", __func__);
+		rc = -ENOMEM;
+		goto err2;
+	}
+
+	afu->gmmio_phys = gmmio;
+	afu->ppmmio_phys = ppmmio;
+out:
+	return rc;
+err2:
+	pci_release_region(pdev, acfg->pp_mmio_bar);
+err1:
+	pci_release_region(pdev, acfg->global_mmio_bar);
+	goto out;
+}
+
 /**
  * ocxlflash_config_afu() - configure the host AFU
  * @pdev:	PCI device associated with the host.
@@ -369,6 +432,13 @@ static int ocxlflash_config_afu(struct pci_dev *pdev, struct ocxl_hw_afu *afu)
 	afu->max_pasid = 1 << acfg->pasid_supported_log;
 
 	ocxl_config_set_afu_pasid(pdev, pos, 0, acfg->pasid_supported_log);
+
+	rc = ocxlflash_map_mmio(afu);
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: ocxlflash_map_mmio failed rc=%d\n",
+			__func__, rc);
+		goto out;
+	}
 out:
 	return rc;
 }
@@ -415,12 +485,14 @@ static void *ocxlflash_create_afu(struct pci_dev *pdev)
 		rc = PTR_ERR(ctx);
 		dev_err(dev, "%s: ocxlflash_dev_context_init failed rc=%d\n",
 			__func__, rc);
-		goto err1;
+		goto err2;
 	}
 
 	afu->ocxl_ctx = ctx;
 out:
 	return afu;
+err2:
+	ocxlflash_unconfig_afu(afu);
 err1:
 	idr_destroy(&afu->idr);
 	kfree(afu);

drivers/scsi/cxlflash/ocxl_hw.h

@@ -27,6 +27,10 @@ struct ocxl_hw_afu {
 	int afu_actag_base;		/* AFU acTag base */
 	int afu_actag_enabled;		/* AFU acTag number enabled */
 
+	phys_addr_t ppmmio_phys;	/* Per process MMIO space */
+	phys_addr_t gmmio_phys;		/* Global AFU MMIO space */
+	void __iomem *gmmio_virt;	/* Global MMIO map */
+
 	struct idr idr;			/* IDR to manage contexts */
 	int max_pasid;			/* Maximum number of contexts */
 	bool is_present;		/* Function has AFUs defined */