PCI: generic, thunder: Use generic ECAM API

Use functions provided by drivers/pci/ecam.h for mapping the config space
in drivers/pci/host/pci-host-common.c, and update its users to use 'struct
pci_config_window' and 'struct pci_ecam_ops'.

The changes are mostly to use 'struct pci_config_window' in place of
'struct gen_pci'.  Some of the fields of gen_pci were only used temporarily
and can be eliminated by using local variables or function arguments, these
are not carried over to struct pci_config_window.

pci-thunder-ecam.c and pci-thunder-pem.c are the only users of the
pci_host_common_probe function and the gen_pci structure; these have been
updated to use the new API as well.

The patch does not introduce any functional changes other than a very minor
one: with the new code, on 64-bit platforms, we do just a single ioremap
for the whole config space.

Signed-off-by: Jayachandran C <jchandra@broadcom.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

1 files changed, 10 insertions, 42 deletions

diff --git a/drivers/pci/host/pci-host-generic.c b/drivers/pci/host/pci-host-generic.c
index e8aa78faa16d..6eaceab1bf04 100644
--- a/drivers/pci/host/pci-host-generic.c
+++ b/drivers/pci/host/pci-host-generic.c
@@ -25,41 +25,12 @@
 #include <linux/of_pci.h>
 #include <linux/platform_device.h>
 
-#include "pci-host-common.h"
+#include "../ecam.h"
 
-static void __iomem *gen_pci_map_cfg_bus_cam(struct pci_bus *bus,
-					     unsigned int devfn,
-					     int where)
-{
-	struct gen_pci *pci = bus->sysdata;
-	resource_size_t idx = bus->number - pci->cfg.bus_range->start;
-
-	return pci->cfg.win[idx] + ((devfn << 8) | where);
-}
-
-static struct gen_pci_cfg_bus_ops gen_pci_cfg_cam_bus_ops = {
+static struct pci_ecam_ops gen_pci_cfg_cam_bus_ops = {
 	.bus_shift	= 16,
-	.ops		= {
-		.map_bus	= gen_pci_map_cfg_bus_cam,
-		.read		= pci_generic_config_read,
-		.write		= pci_generic_config_write,
-	}
-};
-
-static void __iomem *gen_pci_map_cfg_bus_ecam(struct pci_bus *bus,
-					      unsigned int devfn,
-					      int where)
-{
-	struct gen_pci *pci = bus->sysdata;
-	resource_size_t idx = bus->number - pci->cfg.bus_range->start;
-
-	return pci->cfg.win[idx] + ((devfn << 12) | where);
-}
-
-static struct gen_pci_cfg_bus_ops gen_pci_cfg_ecam_bus_ops = {
-	.bus_shift	= 20,
-	.ops		= {
-		.map_bus	= gen_pci_map_cfg_bus_ecam,
+	.pci_ops	= {
+		.map_bus	= pci_ecam_map_bus,
 		.read		= pci_generic_config_read,
 		.write		= pci_generic_config_write,
 	}
@@ -70,25 +41,22 @@ static const struct of_device_id gen_pci_of_match[] = {
 	  .data = &gen_pci_cfg_cam_bus_ops },
 
 	{ .compatible = "pci-host-ecam-generic",
-	  .data = &gen_pci_cfg_ecam_bus_ops },
+	  .data = &pci_generic_ecam_ops },
 
 	{ },
 };
+
 MODULE_DEVICE_TABLE(of, gen_pci_of_match);
 
 static int gen_pci_probe(struct platform_device *pdev)
 {
-	struct device *dev = &pdev->dev;
 	const struct of_device_id *of_id;
-	struct gen_pci *pci = devm_kzalloc(dev, sizeof(*pci), GFP_KERNEL);
-
-	if (!pci)
-		return -ENOMEM;
+	struct pci_ecam_ops *ops;
 
-	of_id = of_match_node(gen_pci_of_match, dev->of_node);
-	pci->cfg.ops = (struct gen_pci_cfg_bus_ops *)of_id->data;
+	of_id = of_match_node(gen_pci_of_match, pdev->dev.of_node);
+	ops = (struct pci_ecam_ops *)of_id->data;
 
-	return pci_host_common_probe(pdev, pci);
+	return pci_host_common_probe(pdev, ops);
 }
 
 static struct platform_driver gen_pci_driver = {