Add NumaChip-specific PCI access mechanism via MMCONFIG cycles, but
preventing access to AMD Northbridges which shouldn't respond.
v2: Use PCI_DEVFN in precomputed constant limit; drop unneeded includes
Signed-off-by: Daniel J Blueman <dan...@numascale-asia.com>
---
arch/x86/include/asm/numachip/numachip.h | 20 +++++
arch/x86/kernel/apic/apic_numachip.c | 2 +
arch/x86/pci/Makefile | 1 +
arch/x86/pci/numachip.c | 134 ++++++++++++++++++++++++++++++
4 files changed, 157 insertions(+)
create mode 100644 arch/x86/include/asm/numachip/numachip.h
create mode 100644 arch/x86/pci/numachip.c
diff --git a/arch/x86/include/asm/numachip/numachip.h
b/arch/x86/include/asm/numachip/numachip.h
new file mode 100644
index 0000000..d35e71a
--- /dev/null
+++ b/arch/x86/include/asm/numachip/numachip.h
@@ -0,0 +1,20 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Numascale NumaConnect-specific header file
+ *
+ * Copyright (C) 2012 Numascale AS. All rights reserved.
+ *
+ * Send feedback to <supp...@numascale.com>
+ *
+ */
+
+#ifndef _ASM_X86_NUMACHIP_NUMACHIP_H
+#define _ASM_X86_NUMACHIP_NUMACHIP_H
+
+extern int __init pci_numachip_init(void);
+
+#endif /* _ASM_X86_NUMACHIP_NUMACHIP_H */
+
diff --git a/arch/x86/kernel/apic/apic_numachip.c
b/arch/x86/kernel/apic/apic_numachip.c
index a65829a..9c2aa89 100644
--- a/arch/x86/kernel/apic/apic_numachip.c
+++ b/arch/x86/kernel/apic/apic_numachip.c
@@ -22,6 +22,7 @@
#include <linux/hardirq.h>
#include <linux/delay.h>
+#include <asm/numachip/numachip.h>
#include <asm/numachip/numachip_csr.h>
#include <asm/smp.h>
#include <asm/apic.h>
@@ -179,6 +180,7 @@ static int __init numachip_system_init(void)
return 0;
x86_cpuinit.fixup_cpu_id = fixup_cpu_id;
+ x86_init.pci.arch_init = pci_numachip_init;
map_csrs();
diff --git a/arch/x86/pci/Makefile b/arch/x86/pci/Makefile
index 3af5a1e..ee0af58 100644
--- a/arch/x86/pci/Makefile
+++ b/arch/x86/pci/Makefile
@@ -16,6 +16,7 @@ obj-$(CONFIG_STA2X11) += sta2x11-fixup.o
obj-$(CONFIG_X86_VISWS) += visws.o
obj-$(CONFIG_X86_NUMAQ) += numaq_32.o
+obj-$(CONFIG_X86_NUMACHIP) += numachip.o
obj-$(CONFIG_X86_INTEL_MID) += mrst.o
diff --git a/arch/x86/pci/numachip.c b/arch/x86/pci/numachip.c
new file mode 100644
index 0000000..3773e05
--- /dev/null
+++ b/arch/x86/pci/numachip.c
@@ -0,0 +1,129 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Numascale NumaConnect-specific PCI code
+ *
+ * Copyright (C) 2012 Numascale AS. All rights reserved.
+ *
+ * Send feedback to <supp...@numascale.com>
+ *
+ * PCI accessor functions derived from mmconfig_64.c
+ *
+ */
+
+#include <linux/pci.h>
+#include <asm/pci_x86.h>
+
+static u8 limit __read_mostly;
+
+static inline 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;
+}
+
+static int pci_mmcfg_read_numachip(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;
+ }
+
+ /* Ensure AMD Northbridges don't decode reads to other devices */
+ if (unlikely(bus == 0 && devfn >= limit)) {
+ *value = -1;
+ return 0;
+ }
+
+ 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;
+}
+
+static int pci_mmcfg_write_numachip(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;
+
+ /* Ensure AMD Northbridges don't decode writes to other devices */
+ if (unlikely(bus == 0 && devfn >= limit))
+ return 0;
+
+ 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_numachip = {
+ .read = pci_mmcfg_read_numachip,
+ .write = pci_mmcfg_write_numachip,
+};
+
+int __init pci_numachip_init(void)
+{
+ int ret = 0;
+ u32 val;
+
+ /* For remote I/O, restrict bus 0 access to the actual number of AMD
+ Northbridges, which starts at device number 0x18 */
+ ret = raw_pci_read(0, 0, PCI_DEVFN(0x18, 0), 0x60, sizeof(val), &val);
+ if (ret)
+ goto out;
+
+ /* HyperTransport fabric size in bits 6:4 */
+ limit = PCI_DEVFN(0x18 + ((val >> 4) & 7) + 1, 0);
+
+ /* Use NumaChip PCI accessors for non-extended and extended access */
+ raw_pci_ops = raw_pci_ext_ops = &pci_mmcfg_numachip;
+out:
+ return ret;
+}
--
1.7.9.5
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