[PATCH v5 06/26] cxl/pci: Refactor component register discovery for reuse

Terry Bowman
2023-06-07T22:18:36Z

The endpoint implements component register setup code. Refactor it for
reuse with RCRB, downstream port, and upstream port setup.

Move PCI specifics from cxl_setup_regs() into cxl_pci_setup_regs().

Move cxl_setup_regs() into cxl/core/regs.c and export it. This also
includes supporting static functions cxl_map_registerblock(),
cxl_unmap_register_block() and cxl_probe_regs().

Co-developed-by: Robert Richter <rrichter@amd.com>
Signed-off-by: Robert Richter <rrichter@amd.com>
Signed-off-by: Terry Bowman <terry.bowman@amd.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
---
drivers/cxl/core/regs.c | 78 ++++++++++++++++++++++++++++++++++++++++
drivers/cxl/cxl.h | 1 +
drivers/cxl/pci.c | 80 +++--------------------------------------
3 files changed, 84 insertions(+), 75 deletions(-)

diff --git a/drivers/cxl/core/regs.c b/drivers/cxl/core/regs.c
index 3b4e56fb36a8..bf80e371ef27 100644
--- a/drivers/cxl/core/regs.c
+++ b/drivers/cxl/core/regs.c
@@ -338,6 +338,84 @@ int cxl_find_regblock(struct pci_dev *pdev, enum cxl_regloc_type type,
}
EXPORT_SYMBOL_NS_GPL(cxl_find_regblock, CXL);

+static int cxl_map_regblock(struct cxl_register_map *map)
+{
+ struct device *dev = map->dev;
+
+ map->base = ioremap(map->resource, map->max_size);
+ if (!map->base) {
+ dev_err(dev, "failed to map registers\n");
+ return -ENOMEM;
+ }
+
+ dev_dbg(dev, "Mapped CXL Memory Device resource %pa\n", &map->resource);
+
+ return 0;
+}
+
+static void cxl_unmap_regblock(struct cxl_register_map *map)
+{
+ iounmap(map->base);
+ map->base = NULL;
+}
+
+static int cxl_probe_regs(struct cxl_register_map *map)
+{
+ struct cxl_component_reg_map *comp_map;
+ struct cxl_device_reg_map *dev_map;
+ struct device *dev = map->dev;
+ void __iomem *base = map->base;
+
+ switch (map->reg_type) {
+ case CXL_REGLOC_RBI_COMPONENT:
+ comp_map = &map->component_map;
+ cxl_probe_component_regs(dev, base, comp_map);
+ if (!comp_map->hdm_decoder.valid) {
+ dev_err(dev, "HDM decoder registers not found\n");
+ return -ENXIO;
+ }
+
+ if (!comp_map->ras.valid)
+ dev_dbg(dev, "RAS registers not found\n");
+
+ dev_dbg(dev, "Set up component registers\n");
+ break;
+ case CXL_REGLOC_RBI_MEMDEV:
+ dev_map = &map->device_map;
+ cxl_probe_device_regs(dev, base, dev_map);
+ if (!dev_map->status.valid || !dev_map->mbox.valid ||
+ !dev_map->memdev.valid) {
+ dev_err(dev, "registers not found: %s%s%s\n",
+ !dev_map->status.valid ? "status " : "",
+ !dev_map->mbox.valid ? "mbox " : "",
+ !dev_map->memdev.valid ? "memdev " : "");
+ return -ENXIO;
+ }
+
+ dev_dbg(dev, "Probing device registers...\n");
+ break;
+ default:
+ break;
+ }
+
+ return 0;
+}
+
+int cxl_setup_regs(struct cxl_register_map *map)
+{
+ int rc;
+
+ rc = cxl_map_regblock(map);
+ if (rc)
+ return rc;
+
+ rc = cxl_probe_regs(map);
+ cxl_unmap_regblock(map);
+
+ return rc;
+}
+EXPORT_SYMBOL_NS_GPL(cxl_setup_regs, CXL);
+
resource_size_t cxl_probe_rcrb(struct device *dev, resource_size_t rcrb,
struct cxl_rcrb_info *ri, enum cxl_rcrb which)
{
diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
index 095b767c21e9..1c6fe53e9dc7 100644
--- a/drivers/cxl/cxl.h
+++ b/drivers/cxl/cxl.h
@@ -264,6 +264,7 @@ int cxl_map_device_regs(struct cxl_register_map *map,
enum cxl_regloc_type;
int cxl_find_regblock(struct pci_dev *pdev, enum cxl_regloc_type type,
struct cxl_register_map *map);
+int cxl_setup_regs(struct cxl_register_map *map);

enum cxl_rcrb {
CXL_RCRB_DOWNSTREAM,
diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c
index 9c1b44f42e49..ac17bc0430dc 100644
--- a/drivers/cxl/pci.c
+++ b/drivers/cxl/pci.c
@@ -274,71 +274,8 @@ static int cxl_pci_setup_mailbox(struct cxl_dev_state *cxlds)
return 0;
}

-static int cxl_map_regblock(struct cxl_register_map *map)
-{
- struct device *dev = map->dev;
-
- map->base = ioremap(map->resource, map->max_size);
- if (!map->base) {
- dev_err(dev, "failed to map registers\n");
- return -ENOMEM;
- }
-
- dev_dbg(dev, "Mapped CXL Memory Device resource %pa\n", &map->resource);
-
- return 0;
-}
-
-static void cxl_unmap_regblock(struct cxl_register_map *map)
-{
- iounmap(map->base);
- map->base = NULL;
-}
-
-static int cxl_probe_regs(struct cxl_register_map *map)
-{
- struct cxl_component_reg_map *comp_map;
- struct cxl_device_reg_map *dev_map;
- struct device *dev = map->dev;
- void __iomem *base = map->base;
-
- switch (map->reg_type) {
- case CXL_REGLOC_RBI_COMPONENT:
- comp_map = &map->component_map;
- cxl_probe_component_regs(dev, base, comp_map);
- if (!comp_map->hdm_decoder.valid) {
- dev_err(dev, "HDM decoder registers not found\n");
- return -ENXIO;
- }
-
- if (!comp_map->ras.valid)
- dev_dbg(dev, "RAS registers not found\n");
-
- dev_dbg(dev, "Set up component registers\n");
- break;
- case CXL_REGLOC_RBI_MEMDEV:
- dev_map = &map->device_map;
- cxl_probe_device_regs(dev, base, dev_map);
- if (!dev_map->status.valid || !dev_map->mbox.valid ||
- !dev_map->memdev.valid) {
- dev_err(dev, "registers not found: %s%s%s\n",
- !dev_map->status.valid ? "status " : "",
- !dev_map->mbox.valid ? "mbox " : "",
- !dev_map->memdev.valid ? "memdev " : "");
- return -ENXIO;
- }
-
- dev_dbg(dev, "Probing device registers...\n");
- break;
- default:
- break;
- }
-
- return 0;
-}
-
-static int cxl_setup_regs(struct pci_dev *pdev, enum cxl_regloc_type type,
- struct cxl_register_map *map)
+static int cxl_pci_setup_regs(struct pci_dev *pdev, enum cxl_regloc_type type,
+ struct cxl_register_map *map)
{
int rc;

@@ -346,14 +283,7 @@ static int cxl_setup_regs(struct pci_dev *pdev, enum cxl_regloc_type type,
if (rc)
return rc;

- rc = cxl_map_regblock(map);
- if (rc)
- return rc;
-
- rc = cxl_probe_regs(map);
- cxl_unmap_regblock(map);
-
- return rc;
+ return cxl_setup_regs(map);
}

/*
@@ -684,7 +614,7 @@ static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
dev_warn(&pdev->dev,
"Device DVSEC not present, skip CXL.mem init\n");

- rc = cxl_setup_regs(pdev, CXL_REGLOC_RBI_MEMDEV, &map);
+ rc = cxl_pci_setup_regs(pdev, CXL_REGLOC_RBI_MEMDEV, &map);
if (rc)
return rc;

@@ -697,7 +627,7 @@ static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
* still be useful for management functions so don't return an error.
*/
cxlds->component_reg_phys = CXL_RESOURCE_NONE;
- rc = cxl_setup_regs(pdev, CXL_REGLOC_RBI_COMPONENT, &map);
+ rc = cxl_pci_setup_regs(pdev, CXL_REGLOC_RBI_COMPONENT, &map);
if (rc)
dev_warn(&pdev->dev, "No component registers (%d)\n", rc);

--
2.34.1