[PATCH] shpchp: fix improper mmio mapping

Current SHPCHP driver seems not to map MMIO region properly. This
patch fixes this bug. This patch also cleanup the code.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 46 insertions, 27 deletions

diff --git a/drivers/pci/hotplug/shpchp_hpc.c b/drivers/pci/hotplug/shpchp_hpc.c
index f5a8bf374634..d82987f075b2 100644
--- a/drivers/pci/hotplug/shpchp_hpc.c
+++ b/drivers/pci/hotplug/shpchp_hpc.c
@@ -791,7 +791,7 @@ static void hpc_release_ctlr(struct controller *ctrl)
         }
         if (php_ctlr->pci_dev) {
                 iounmap(php_ctlr->creg);
-                release_mem_region(pci_resource_start(php_ctlr->pci_dev, 0), pci_resource_len(php_ctlr->pci_dev, 0));
+                release_mem_region(ctrl->mmio_base, ctrl->mmio_size);
                 php_ctlr->pci_dev = NULL;
         }
 
@@ -1320,19 +1320,34 @@ static struct hpc_ops shpchp_hpc_ops = {
         .check_cmd_status               = hpc_check_cmd_status,
 };
 
+inline static int shpc_indirect_creg_read(struct controller *ctrl, int index,
+                                          u32 *value)
+{
+        int rc;
+        u32 cap_offset = ctrl->cap_offset;
+        struct pci_dev *pdev = ctrl->pci_dev;
+
+        rc = pci_write_config_byte(pdev, cap_offset + DWORD_SELECT, index);
+        if (rc)
+                return rc;
+        return pci_read_config_dword(pdev, cap_offset + DWORD_DATA, value);
+}
+
 int shpc_init(struct controller * ctrl, struct pci_dev * pdev)
 {
         struct php_ctlr_state_s *php_ctlr, *p;
         void *instance_id = ctrl;
-        int rc;
+        int rc, num_slots = 0;
         u8 hp_slot;
         static int first = 1;
-        u32 shpc_cap_offset, shpc_base_offset;
+        u32 shpc_base_offset;
         u32 tempdword, slot_reg;
         u8 i;
 
         DBG_ENTER_ROUTINE
 
+        ctrl->pci_dev = pdev;  /* pci_dev of the P2P bridge */
+
         spin_lock_init(&list_lock);
         php_ctlr = (struct php_ctlr_state_s *) kmalloc(sizeof(struct php_ctlr_state_s), GFP_KERNEL);
 
@@ -1347,41 +1362,45 @@ int shpc_init(struct controller * ctrl, struct pci_dev * pdev)
 
         if ((pdev->vendor == PCI_VENDOR_ID_AMD) || (pdev->device ==
                                 PCI_DEVICE_ID_AMD_GOLAM_7450)) {
-                shpc_base_offset = 0;  /* amd shpc driver doesn't use this; assume 0 */
+                /* amd shpc driver doesn't use Base Offset; assume 0 */
+                ctrl->mmio_base = pci_resource_start(pdev, 0);
+                ctrl->mmio_size = pci_resource_len(pdev, 0);
         } else {
-                if ((shpc_cap_offset = pci_find_capability(pdev, PCI_CAP_ID_SHPC)) == 0) {
-                        err("%s : shpc_cap_offset == 0\n", __FUNCTION__);
+                ctrl->cap_offset = pci_find_capability(pdev, PCI_CAP_ID_SHPC);
+                if (!ctrl->cap_offset) {
+                        err("%s : cap_offset == 0\n", __FUNCTION__);
                         goto abort_free_ctlr;
                 }
-                dbg("%s: shpc_cap_offset = %x\n", __FUNCTION__, shpc_cap_offset);       
-        
-                rc = pci_write_config_byte(pdev, (u8)shpc_cap_offset + DWORD_SELECT , BASE_OFFSET);
+                dbg("%s: cap_offset = %x\n", __FUNCTION__, ctrl->cap_offset);
+
+                rc = shpc_indirect_creg_read(ctrl, 0, &shpc_base_offset);
                 if (rc) {
-                        err("%s : pci_word_config_byte failed\n", __FUNCTION__);
+                        err("%s: cannot read base_offset\n", __FUNCTION__);
                         goto abort_free_ctlr;
                 }
-        
-                rc = pci_read_config_dword(pdev, (u8)shpc_cap_offset + DWORD_DATA, &shpc_base_offset);
+
+                rc = shpc_indirect_creg_read(ctrl, 3, &tempdword);
                 if (rc) {
-                        err("%s : pci_read_config_dword failed\n", __FUNCTION__);
+                        err("%s: cannot read slot config\n", __FUNCTION__);
                         goto abort_free_ctlr;
                 }
+                num_slots = tempdword & SLOT_NUM;
+                dbg("%s: num_slots (indirect) %x\n", __FUNCTION__, num_slots);
 
-                for (i = 0; i <= 14; i++) {
-                        rc = pci_write_config_byte(pdev, (u8)shpc_cap_offset +  DWORD_SELECT , i);
-                        if (rc) {
-                                err("%s : pci_word_config_byte failed\n", __FUNCTION__);
-                                goto abort_free_ctlr;
-                        }
-        
-                        rc = pci_read_config_dword(pdev, (u8)shpc_cap_offset + DWORD_DATA, &tempdword);
+                for (i = 0; i < 9 + num_slots; i++) {
+                        rc = shpc_indirect_creg_read(ctrl, i, &tempdword);
                         if (rc) {
-                                err("%s : pci_read_config_dword failed\n", __FUNCTION__);
+                                err("%s: cannot read creg (index = %d)\n",
+                                    __FUNCTION__, i);
                                 goto abort_free_ctlr;
                         }
                         dbg("%s: offset %d: value %x\n", __FUNCTION__,i,
                                         tempdword);
                 }
+
+                ctrl->mmio_base =
+                        pci_resource_start(pdev, 0) + shpc_base_offset;
+                ctrl->mmio_size = 0x24 + 0x4 * num_slots;
         }
 
         if (first) {
@@ -1395,16 +1414,16 @@ int shpc_init(struct controller * ctrl, struct pci_dev * pdev)
         if (pci_enable_device(pdev))
                 goto abort_free_ctlr;
 
-        if (!request_mem_region(pci_resource_start(pdev, 0) + shpc_base_offset, pci_resource_len(pdev, 0), MY_NAME)) {
+        if (!request_mem_region(ctrl->mmio_base, ctrl->mmio_size, MY_NAME)) {
                 err("%s: cannot reserve MMIO region\n", __FUNCTION__);
                 goto abort_free_ctlr;
         }
 
-        php_ctlr->creg = ioremap(pci_resource_start(pdev, 0) + shpc_base_offset, pci_resource_len(pdev, 0));
+        php_ctlr->creg = ioremap(ctrl->mmio_base, ctrl->mmio_size);
         if (!php_ctlr->creg) {
-                err("%s: cannot remap MMIO region %lx @ %lx\n", __FUNCTION__, pci_resource_len(pdev, 0), 
-                        pci_resource_start(pdev, 0) + shpc_base_offset);
-                release_mem_region(pci_resource_start(pdev, 0) + shpc_base_offset, pci_resource_len(pdev, 0));
+                err("%s: cannot remap MMIO region %lx @ %lx\n", __FUNCTION__,
+                    ctrl->mmio_size, ctrl->mmio_base);
+                release_mem_region(ctrl->mmio_base, ctrl->mmio_size);
                 goto abort_free_ctlr;
         }
         dbg("%s: php_ctlr->creg %p\n", __FUNCTION__, php_ctlr->creg);