cxl/mem: Move register locator logic into reg setup

Start moving code around to ultimately get rid of @cxlm.base. The
@cxlm.base member serves no purpose other than intermediate storage of
the offset found in cxl_mem_map_regblock() later used by
cxl_mem_setup_regs(). Aside from wanting to get rid of this useless
member, it will help later when adding new register block identifiers.

While @cxlm.base still exists, it will become trivial to remove it in a
future patch.

No functional change is meant to be introduced in this patch.

Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/20210407222625.320177-4-ben.widawsky@intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c
index be6936c..df6ccdc 100644 (file)
--- a/drivers/cxl/pci.c
+++ b/drivers/cxl/pci.c
@@ -870,34 +870,6 @@ static int cxl_mem_mbox_send_cmd(struct cxl_mem *cxlm, u16 opcode,
        return 0;
 }
 
-/**
- * cxl_mem_setup_regs() - Setup necessary MMIO.
- * @cxlm: The CXL memory device to communicate with.
- *
- * Return: 0 if all necessary registers mapped.
- *
- * A memory device is required by spec to implement a certain set of MMIO
- * regions. The purpose of this function is to enumerate and map those
- * registers.
- */
-static int cxl_mem_setup_regs(struct cxl_mem *cxlm)
-{
-       struct device *dev = &cxlm->pdev->dev;
-       struct cxl_regs *regs = &cxlm->regs;
-
-       cxl_setup_device_regs(dev, cxlm->base, &regs->device_regs);
-
-       if (!regs->status || !regs->mbox || !regs->memdev) {
-               dev_err(dev, "registers not found: %s%s%s\n",
-                       !regs->status ? "status " : "",
-                       !regs->mbox ? "mbox " : "",
-                       !regs->memdev ? "memdev" : "");
-               return -ENXIO;
-       }
-
-       return 0;
-}
-
 static int cxl_mem_setup_mailbox(struct cxl_mem *cxlm)
 {
        const int cap = readl(cxlm->regs.mbox + CXLDEV_MBOX_CAPS_OFFSET);
@@ -1005,6 +977,73 @@ static int cxl_mem_dvsec(struct pci_dev *pdev, int dvsec)
        return 0;
 }
 
+/**
+ * cxl_mem_setup_regs() - Setup necessary MMIO.
+ * @cxlm: The CXL memory device to communicate with.
+ *
+ * Return: 0 if all necessary registers mapped.
+ *
+ * A memory device is required by spec to implement a certain set of MMIO
+ * regions. The purpose of this function is to enumerate and map those
+ * registers.
+ */
+static int cxl_mem_setup_regs(struct cxl_mem *cxlm)
+{
+       struct cxl_regs *regs = &cxlm->regs;
+       struct pci_dev *pdev = cxlm->pdev;
+       struct device *dev = &pdev->dev;
+       u32 regloc_size, regblocks;
+       int rc, regloc, i;
+
+       regloc = cxl_mem_dvsec(pdev, PCI_DVSEC_ID_CXL_REGLOC_OFFSET);
+       if (!regloc) {
+               dev_err(dev, "register location dvsec not found\n");
+               return -ENXIO;
+       }
+
+       /* Get the size of the Register Locator DVSEC */
+       pci_read_config_dword(pdev, regloc + PCI_DVSEC_HEADER1, &regloc_size);
+       regloc_size = FIELD_GET(PCI_DVSEC_HEADER1_LENGTH_MASK, regloc_size);
+
+       regloc += PCI_DVSEC_ID_CXL_REGLOC_BLOCK1_OFFSET;
+       regblocks = (regloc_size - PCI_DVSEC_ID_CXL_REGLOC_BLOCK1_OFFSET) / 8;
+
+       for (i = 0; i < regblocks; i++, regloc += 8) {
+               u32 reg_lo, reg_hi;
+               u8 reg_type;
+
+               /* "register low and high" contain other bits */
+               pci_read_config_dword(pdev, regloc, &reg_lo);
+               pci_read_config_dword(pdev, regloc + 4, &reg_hi);
+
+               reg_type = FIELD_GET(CXL_REGLOC_RBI_MASK, reg_lo);
+
+               if (reg_type == CXL_REGLOC_RBI_MEMDEV) {
+                       rc = cxl_mem_map_regblock(cxlm, reg_lo, reg_hi);
+                       if (rc)
+                               return rc;
+                       break;
+               }
+       }
+
+       if (i == regblocks) {
+               dev_err(dev, "Missing register locator for device registers\n");
+               return -ENXIO;
+       }
+
+       cxl_setup_device_regs(dev, cxlm->base, &regs->device_regs);
+
+       if (!regs->status || !regs->mbox || !regs->memdev) {
+               dev_err(dev, "registers not found: %s%s%s\n",
+                       !regs->status ? "status " : "",
+                       !regs->mbox ? "mbox " : "",
+                       !regs->memdev ? "memdev" : "");
+               return -ENXIO;
+       }
+
+       return 0;
+}
+
 static struct cxl_memdev *to_cxl_memdev(struct device *dev)
 {
        return container_of(dev, struct cxl_memdev, dev);
@@ -1424,10 +1463,8 @@ static int cxl_mem_identify(struct cxl_mem *cxlm)
 
 static int cxl_mem_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 {
-       struct device *dev = &pdev->dev;
-       u32 regloc_size, regblocks;
        struct cxl_mem *cxlm;
-       int rc, regloc, i;
+       int rc;
 
        rc = pcim_enable_device(pdev);
        if (rc)
@@ -1437,42 +1474,6 @@ static int cxl_mem_probe(struct pci_dev *pdev, const struct pci_device_id *id)
        if (IS_ERR(cxlm))
                return PTR_ERR(cxlm);
 
-       regloc = cxl_mem_dvsec(pdev, PCI_DVSEC_ID_CXL_REGLOC_OFFSET);
-       if (!regloc) {
-               dev_err(dev, "register location dvsec not found\n");
-               return -ENXIO;
-       }
-
-       /* Get the size of the Register Locator DVSEC */
-       pci_read_config_dword(pdev, regloc + PCI_DVSEC_HEADER1, &regloc_size);
-       regloc_size = FIELD_GET(PCI_DVSEC_HEADER1_LENGTH_MASK, regloc_size);
-
-       regloc += PCI_DVSEC_ID_CXL_REGLOC_BLOCK1_OFFSET;
-       regblocks = (regloc_size - PCI_DVSEC_ID_CXL_REGLOC_BLOCK1_OFFSET) / 8;
-
-       for (i = 0; i < regblocks; i++, regloc += 8) {
-               u32 reg_lo, reg_hi;
-               u8 reg_type;
-
-               /* "register low and high" contain other bits */
-               pci_read_config_dword(pdev, regloc, &reg_lo);
-               pci_read_config_dword(pdev, regloc + 4, &reg_hi);
-
-               reg_type = FIELD_GET(CXL_REGLOC_RBI_MASK, reg_lo);
-
-               if (reg_type == CXL_REGLOC_RBI_MEMDEV) {
-                       rc = cxl_mem_map_regblock(cxlm, reg_lo, reg_hi);
-                       if (rc)
-                               return rc;
-                       break;
-               }
-       }
-
-       if (i == regblocks) {
-               dev_err(dev, "Missing register locator for device registers\n");
-               return -ENXIO;
-       }
-
        rc = cxl_mem_setup_regs(cxlm);
        if (rc)
                return rc;