[PATCH 5/6] x86, acpi, pci: mmconfig_64.c becomes default implementation for arch agnostic low-level direct PCI config space accessors via MMCONFIG.

From: Tomasz Nowicki
Date: Wed Nov 19 2014 - 11:05:50 EST


Note that x86 32bits machines still have its own low-level direct
PCI config space accessors.

Signed-off-by: Tomasz Nowicki <tomasz.nowicki@xxxxxxxxxx>
---
arch/x86/pci/Makefile | 5 +-
arch/x86/pci/mmconfig_64.c | 152 ---------------------------------------------
drivers/acpi/mmconfig.c | 134 +++++++++++++++++++++++++++++++++++++++
3 files changed, 138 insertions(+), 153 deletions(-)
delete mode 100644 arch/x86/pci/mmconfig_64.c

diff --git a/arch/x86/pci/Makefile b/arch/x86/pci/Makefile
index 5c6fc35..35c765b 100644
--- a/arch/x86/pci/Makefile
+++ b/arch/x86/pci/Makefile
@@ -1,7 +1,10 @@
obj-y := i386.o init.o

obj-$(CONFIG_PCI_BIOS) += pcbios.o
-obj-$(CONFIG_PCI_MMCONFIG) += mmconfig_$(BITS).o direct.o mmconfig-shared.o
+obj-$(CONFIG_PCI_MMCONFIG) += direct.o mmconfig-shared.o
+ifeq ($(BITS),32)
+obj-$(CONFIG_PCI_MMCONFIG) += mmconfig_32.o
+endif
obj-$(CONFIG_PCI_DIRECT) += direct.o
obj-$(CONFIG_PCI_OLPC) += olpc.o
obj-$(CONFIG_PCI_XEN) += xen.o
diff --git a/arch/x86/pci/mmconfig_64.c b/arch/x86/pci/mmconfig_64.c
deleted file mode 100644
index ff2c50c..0000000
--- a/arch/x86/pci/mmconfig_64.c
+++ /dev/null
@@ -1,152 +0,0 @@
-/*
- * mmconfig.c - Low-level direct PCI config space access via MMCONFIG
- *
- * This is an 64bit optimized version that always keeps the full mmconfig
- * space mapped. This allows lockless config space operation.
- */
-
-#include <linux/pci.h>
-#include <linux/init.h>
-#include <linux/acpi.h>
-#include <linux/bitmap.h>
-#include <linux/rcupdate.h>
-#include <linux/mmconfig.h>
-#include <asm/e820.h>
-#include <asm/pci_x86.h>
-
-#define PREFIX "PCI: "
-
-static char __iomem *pci_dev_base(unsigned int seg, unsigned int bus, unsigned int devfn)
-{
- struct pci_mmcfg_region *cfg = pci_mmconfig_lookup(seg, bus);
-
- if (cfg && cfg->virt)
- return cfg->virt + (PCI_MMCFG_BUS_OFFSET(bus) | (devfn << 12));
- return NULL;
-}
-
-int pci_mmcfg_read(unsigned int seg, unsigned int bus,
- unsigned int devfn, int reg, int len, u32 *value)
-{
- char __iomem *addr;
-
- /* Why do we have this when nobody checks it. How about a BUG()!? -AK */
- if (unlikely((bus > 255) || (devfn > 255) || (reg > 4095))) {
-err: *value = -1;
- return -EINVAL;
- }
-
- rcu_read_lock();
- addr = pci_dev_base(seg, bus, devfn);
- if (!addr) {
- rcu_read_unlock();
- goto err;
- }
-
- switch (len) {
- case 1:
- *value = mmio_config_readb(addr + reg);
- break;
- case 2:
- *value = mmio_config_readw(addr + reg);
- break;
- case 4:
- *value = mmio_config_readl(addr + reg);
- break;
- }
- rcu_read_unlock();
-
- return 0;
-}
-
-int pci_mmcfg_write(unsigned int seg, unsigned int bus,
- unsigned int devfn, int reg, int len, u32 value)
-{
- char __iomem *addr;
-
- /* Why do we have this when nobody checks it. How about a BUG()!? -AK */
- if (unlikely((bus > 255) || (devfn > 255) || (reg > 4095)))
- return -EINVAL;
-
- rcu_read_lock();
- addr = pci_dev_base(seg, bus, devfn);
- if (!addr) {
- rcu_read_unlock();
- return -EINVAL;
- }
-
- switch (len) {
- case 1:
- mmio_config_writeb(addr + reg, value);
- break;
- case 2:
- mmio_config_writew(addr + reg, value);
- break;
- case 4:
- mmio_config_writel(addr + reg, value);
- break;
- }
- rcu_read_unlock();
-
- return 0;
-}
-
-const struct pci_raw_ops pci_mmcfg = {
- .read = pci_mmcfg_read,
- .write = pci_mmcfg_write,
-};
-
-static void __iomem *mcfg_ioremap(struct pci_mmcfg_region *cfg)
-{
- void __iomem *addr;
- u64 start, size;
- int num_buses;
-
- start = cfg->address + PCI_MMCFG_BUS_OFFSET(cfg->start_bus);
- num_buses = cfg->end_bus - cfg->start_bus + 1;
- size = PCI_MMCFG_BUS_OFFSET(num_buses);
- addr = ioremap_nocache(start, size);
- if (addr)
- addr -= PCI_MMCFG_BUS_OFFSET(cfg->start_bus);
- return addr;
-}
-
-int __init pci_mmcfg_arch_init(void)
-{
- struct pci_mmcfg_region *cfg;
-
- list_for_each_entry(cfg, &pci_mmcfg_list, list)
- if (pci_mmcfg_arch_map(cfg)) {
- pci_mmcfg_arch_free();
- return 0;
- }
-
- return 1;
-}
-
-void __init pci_mmcfg_arch_free(void)
-{
- struct pci_mmcfg_region *cfg;
-
- list_for_each_entry(cfg, &pci_mmcfg_list, list)
- pci_mmcfg_arch_unmap(cfg);
-}
-
-int pci_mmcfg_arch_map(struct pci_mmcfg_region *cfg)
-{
- cfg->virt = mcfg_ioremap(cfg);
- if (!cfg->virt) {
- pr_err(PREFIX "can't map MMCONFIG at %pR\n", &cfg->res);
- return -ENOMEM;
- }
-
- return 0;
-}
-
-void pci_mmcfg_arch_unmap(struct pci_mmcfg_region *cfg)
-{
- if (cfg && cfg->virt) {
- iounmap(cfg->virt + PCI_MMCFG_BUS_OFFSET(cfg->start_bus));
- cfg->virt = NULL;
- }
-}
diff --git a/drivers/acpi/mmconfig.c b/drivers/acpi/mmconfig.c
index d62dccda..c0ad05f 100644
--- a/drivers/acpi/mmconfig.c
+++ b/drivers/acpi/mmconfig.c
@@ -12,14 +12,148 @@

#include <linux/mutex.h>
#include <linux/rculist.h>
+#include <linux/pci.h>
#include <linux/mmconfig.h>

+#include <asm/pci.h>
+
#define PREFIX "PCI: "

static DEFINE_MUTEX(pci_mmcfg_lock);

LIST_HEAD(pci_mmcfg_list);

+static char __iomem *pci_dev_base(unsigned int seg, unsigned int bus,
+ unsigned int devfn)
+{
+ struct pci_mmcfg_region *cfg = pci_mmconfig_lookup(seg, bus);
+
+ if (cfg && cfg->virt)
+ return cfg->virt + (PCI_MMCFG_BUS_OFFSET(bus) | (devfn << 12));
+ return NULL;
+}
+
+int __weak pci_mmcfg_read(unsigned int seg, unsigned int bus,
+ unsigned int devfn, int reg, int len, u32 *value)
+{
+ char __iomem *addr;
+
+ /* Why do we have this when nobody checks it. How about a BUG()!? -AK */
+ if (unlikely((bus > 255) || (devfn > 255) || (reg > 4095))) {
+err: *value = -1;
+ return -EINVAL;
+ }
+
+ rcu_read_lock();
+ addr = pci_dev_base(seg, bus, devfn);
+ if (!addr) {
+ rcu_read_unlock();
+ goto err;
+ }
+
+ switch (len) {
+ case 1:
+ *value = mmio_config_readb(addr + reg);
+ break;
+ case 2:
+ *value = mmio_config_readw(addr + reg);
+ break;
+ case 4:
+ *value = mmio_config_readl(addr + reg);
+ break;
+ }
+ rcu_read_unlock();
+
+ return 0;
+}
+
+int __weak pci_mmcfg_write(unsigned int seg, unsigned int bus,
+ unsigned int devfn, int reg, int len, u32 value)
+{
+ char __iomem *addr;
+
+ /* Why do we have this when nobody checks it. How about a BUG()!? -AK */
+ if (unlikely((bus > 255) || (devfn > 255) || (reg > 4095)))
+ return -EINVAL;
+
+ rcu_read_lock();
+ addr = pci_dev_base(seg, bus, devfn);
+ if (!addr) {
+ rcu_read_unlock();
+ return -EINVAL;
+ }
+
+ switch (len) {
+ case 1:
+ mmio_config_writeb(addr + reg, value);
+ break;
+ case 2:
+ mmio_config_writew(addr + reg, value);
+ break;
+ case 4:
+ mmio_config_writel(addr + reg, value);
+ break;
+ }
+ rcu_read_unlock();
+
+ return 0;
+}
+
+static void __iomem *mcfg_ioremap(struct pci_mmcfg_region *cfg)
+{
+ void __iomem *addr;
+ u64 start, size;
+ int num_buses;
+
+ start = cfg->address + PCI_MMCFG_BUS_OFFSET(cfg->start_bus);
+ num_buses = cfg->end_bus - cfg->start_bus + 1;
+ size = PCI_MMCFG_BUS_OFFSET(num_buses);
+ addr = ioremap_nocache(start, size);
+ if (addr)
+ addr -= PCI_MMCFG_BUS_OFFSET(cfg->start_bus);
+ return addr;
+}
+
+int __init __weak pci_mmcfg_arch_init(void)
+{
+ struct pci_mmcfg_region *cfg;
+
+ list_for_each_entry(cfg, &pci_mmcfg_list, list)
+ if (pci_mmcfg_arch_map(cfg)) {
+ pci_mmcfg_arch_free();
+ return 0;
+ }
+
+ return 1;
+}
+
+void __init __weak pci_mmcfg_arch_free(void)
+{
+ struct pci_mmcfg_region *cfg;
+
+ list_for_each_entry(cfg, &pci_mmcfg_list, list)
+ pci_mmcfg_arch_unmap(cfg);
+}
+
+int __weak pci_mmcfg_arch_map(struct pci_mmcfg_region *cfg)
+{
+ cfg->virt = mcfg_ioremap(cfg);
+ if (!cfg->virt) {
+ pr_err(PREFIX "can't map MMCONFIG at %pR\n", &cfg->res);
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+void __weak pci_mmcfg_arch_unmap(struct pci_mmcfg_region *cfg)
+{
+ if (cfg && cfg->virt) {
+ iounmap(cfg->virt + PCI_MMCFG_BUS_OFFSET(cfg->start_bus));
+ cfg->virt = NULL;
+ }
+}
+
static void __init pci_mmconfig_remove(struct pci_mmcfg_region *cfg)
{
if (cfg->res.parent)
--
1.9.1

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