[PATCH] x86_64: Inclusion of ScaleMP vSMP architecture patches - vsmp_arch

Introduce vSMP arch to the kernel.

This patch:
1. Adds CONFIG_X86_VSMP
2. Adds machine specific macros for local_irq_disabled, local_irq_enabled
   and irqs_disabled
3. Writes to the vSMP CTL device to indicate kernel compiled with CONFIG_VSMP

Signed-off-by: Ravikiran Thirumalai <kiran@scalemp.com>
Signed-off-by: Shai Fultheim <shai@scalemp.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

5 files changed, 85 insertions, 0 deletions

diff --git a/arch/x86_64/Kconfig b/arch/x86_64/Kconfig
index ee053e32a721..2efc4be22709 100644
--- a/arch/x86_64/Kconfig
+++ b/arch/x86_64/Kconfig
@@ -79,6 +79,24 @@ source "init/Kconfig"
 menu "Processor type and features"
 
 choice
+        prompt "Subarchitecture Type"
+        default X86_PC
+
+config X86_PC
+        bool "PC-compatible"
+        help
+          Choose this option if your computer is a standard PC or compatible.
+
+config X86_VSMP
+        bool "Support for ScaleMP vSMP"
+         help
+          Support for ScaleMP vSMP systems.  Say 'Y' here if this kernel is
+          supposed to run on these EM64T-based machines.  Only choose this option
+          if you have one of these machines.
+
+endchoice
+
+choice
         prompt "Processor family"
         default MK8
 
diff --git a/arch/x86_64/kernel/Makefile b/arch/x86_64/kernel/Makefile
index 7df09edb36a1..72fe60c20d39 100644
--- a/arch/x86_64/kernel/Makefile
+++ b/arch/x86_64/kernel/Makefile
@@ -32,6 +32,7 @@ obj-$(CONFIG_GART_IOMMU)	+= pci-gart.o aperture.o
 obj-$(CONFIG_SWIOTLB)           += pci-swiotlb.o
 obj-$(CONFIG_KPROBES)           += kprobes.o
 obj-$(CONFIG_X86_PM_TIMER)      += pmtimer.o
+obj-$(CONFIG_X86_VSMP)          += vsmp.o
 
 obj-$(CONFIG_MODULES)           += module.o
 
diff --git a/arch/x86_64/kernel/vsmp.c b/arch/x86_64/kernel/vsmp.c
new file mode 100644
index 000000000000..92f70c74965f
--- /dev/null
+++ b/arch/x86_64/kernel/vsmp.c
@@ -0,0 +1,45 @@
+/*
+ * vSMPowered(tm) systems specific initialization
+ * Copyright (C) 2005 ScaleMP Inc.
+ *
+ * Use of this code is subject to the terms and conditions of the
+ * GNU general public license version 2. See "COPYING" or
+ * http://www.gnu.org/licenses/gpl.html
+ *
+ * Ravikiran Thirumalai <kiran@scalemp.com>,
+ * Shai Fultheim <shai@scalemp.com>
+ */
+
+#include <linux/init.h>
+#include <linux/pci_ids.h>
+#include <linux/pci_regs.h>
+#include <asm/pci-direct.h>
+
+static int __init vsmp_init(void)
+{
+        void *address;
+        unsigned int cap, ctl;
+
+        /* Check if we are running on a ScaleMP vSMP box */
+        if ((read_pci_config_16(0, 0x1f, 0, PCI_VENDOR_ID) != PCI_VENDOR_ID_SCALEMP) ||
+            (read_pci_config_16(0, 0x1f, 0, PCI_DEVICE_ID) != PCI_DEVICE_ID_SCALEMP_VSMP_CTL))
+                return 0;
+
+        /* set vSMP magic bits to indicate vSMP capable kernel */
+        address = ioremap(read_pci_config(0, 0x1f, 0, PCI_BASE_ADDRESS_0), 8);
+        cap = readl(address);
+        ctl = readl(address + 4);
+        printk("vSMP CTL: capabilities:0x%08x  control:0x%08x\n", cap, ctl);
+        if (cap & ctl & (1 << 4)) {
+                /* Turn on vSMP IRQ fastpath handling (see system.h) */
+                ctl &= ~(1 << 4);
+                writel(ctl, address + 4);
+                ctl = readl(address + 4);
+                printk("vSMP CTL: control set to:0x%08x\n", ctl);
+        }
+
+        iounmap(address);
+        return 0;
+}
+
+core_initcall(vsmp_init);
diff --git a/include/asm-x86_64/system.h b/include/asm-x86_64/system.h
index 80272190570e..38c1e8a69c9c 100644
--- a/include/asm-x86_64/system.h
+++ b/include/asm-x86_64/system.h
@@ -326,8 +326,25 @@ static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old,
 /* interrupt control.. */
 #define local_save_flags(x)     do { warn_if_not_ulong(x); __asm__ __volatile__("# save_flags \n\t pushfq ; popq %q0":"=g" (x): /* no input */ :"memory"); } while (0)
 #define local_irq_restore(x)    __asm__ __volatile__("# restore_flags \n\t pushq %0 ; popfq": /* no output */ :"g" (x):"memory", "cc")
+
+#ifdef CONFIG_X86_VSMP
+/* Interrupt control for VSMP  architecture */
+#define local_irq_disable()     do { unsigned long flags; local_save_flags(flags); local_irq_restore((flags & ~(1 << 9)) | (1 << 18)); } while (0)
+#define local_irq_enable()      do { unsigned long flags; local_save_flags(flags); local_irq_restore((flags | (1 << 9)) & ~(1 << 18)); } while (0)
+
+#define irqs_disabled()                                 \
+({                                                      \
+        unsigned long flags;                            \
+        local_save_flags(flags);                        \
+        (flags & (1<<18)) || !(flags & (1<<9));         \
+})
+
+/* For spinlocks etc */
+#define local_irq_save(x)       do { local_save_flags(x); local_irq_restore((x & ~(1 << 9)) | (1 << 18)); } while (0)
+#else  /* CONFIG_X86_VSMP */
 #define local_irq_disable()     __asm__ __volatile__("cli": : :"memory")
 #define local_irq_enable()      __asm__ __volatile__("sti": : :"memory")
+
 /* used in the idle loop; sti takes one instruction cycle to complete */
 #define safe_halt()             __asm__ __volatile__("sti; hlt": : :"memory")
 /* used when interrupts are already enabled or to shutdown the processor */
@@ -342,6 +359,7 @@ static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old,
 
 /* For spinlocks etc */
 #define local_irq_save(x)       do { warn_if_not_ulong(x); __asm__ __volatile__("# local_irq_save \n\t pushfq ; popq %0 ; cli":"=g" (x): /* no input */ :"memory"); } while (0)
+#endif
 
 void cpu_idle_wait(void);
 
diff --git a/include/linux/pci_ids.h b/include/linux/pci_ids.h
index f55c98a68aa9..7fb397e3f2d3 100644
--- a/include/linux/pci_ids.h
+++ b/include/linux/pci_ids.h
@@ -2152,6 +2152,9 @@
 #define PCI_DEVICE_ID_INTEL_IXP2800     0x9004
 #define PCI_DEVICE_ID_INTEL_S21152BB    0xb152
 
+#define PCI_VENDOR_ID_SCALEMP           0x8686
+#define PCI_DEVICE_ID_SCALEMP_VSMP_CTL  0x1010
+
 #define PCI_VENDOR_ID_COMPUTONE         0x8e0e
 #define PCI_DEVICE_ID_COMPUTONE_IP2EX   0x0291
 #define PCI_DEVICE_ID_COMPUTONE_PG      0x0302