[IA64] pvops: add hooks, pv_iosapic_ops, to paravirtualize iosapic.

add hooks to paravirtualize iosapic which is a real hardware resource.
On virtualized environment it may be replaced something virtualized
friendly.
Define pv_iosapic_ops and add the hooks.

Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: Tony Luck <tony.luck@intel.com>

4 files changed, 110 insertions, 18 deletions

diff --git a/arch/ia64/kernel/iosapic.c b/arch/ia64/kernel/iosapic.c
index 082c31dcfd99..587196dd84fd 100644
--- a/arch/ia64/kernel/iosapic.c
+++ b/arch/ia64/kernel/iosapic.c
@@ -587,6 +587,15 @@ static inline int irq_is_shared (int irq)
         return (iosapic_intr_info[irq].count > 1);
 }
 
+struct irq_chip*
+ia64_native_iosapic_get_irq_chip(unsigned long trigger)
+{
+        if (trigger == IOSAPIC_EDGE)
+                return &irq_type_iosapic_edge;
+        else
+                return &irq_type_iosapic_level;
+}
+
 static int
 register_intr (unsigned int gsi, int irq, unsigned char delivery,
                unsigned long polarity, unsigned long trigger)
@@ -637,13 +646,10 @@ register_intr (unsigned int gsi, int irq, unsigned char delivery,
         iosapic_intr_info[irq].dmode    = delivery;
         iosapic_intr_info[irq].trigger  = trigger;
 
-        if (trigger == IOSAPIC_EDGE)
-                irq_type = &irq_type_iosapic_edge;
-        else
-                irq_type = &irq_type_iosapic_level;
+        irq_type = iosapic_get_irq_chip(trigger);
 
         idesc = irq_desc + irq;
-        if (idesc->chip != irq_type) {
+        if (irq_type != NULL && idesc->chip != irq_type) {
                 if (idesc->chip != &no_irq_type)
                         printk(KERN_WARNING
                                "%s: changing vector %d from %s to %s\n",
@@ -976,6 +982,22 @@ iosapic_override_isa_irq (unsigned int isa_irq, unsigned int gsi,
 }
 
 void __init
+ia64_native_iosapic_pcat_compat_init(void)
+{
+        if (pcat_compat) {
+                /*
+                 * Disable the compatibility mode interrupts (8259 style),
+                 * needs IN/OUT support enabled.
+                 */
+                printk(KERN_INFO
+                       "%s: Disabling PC-AT compatible 8259 interrupts\n",
+                       __func__);
+                outb(0xff, 0xA1);
+                outb(0xff, 0x21);
+        }
+}
+
+void __init
 iosapic_system_init (int system_pcat_compat)
 {
         int irq;
@@ -989,17 +1011,8 @@ iosapic_system_init (int system_pcat_compat)
         }
 
         pcat_compat = system_pcat_compat;
-        if (pcat_compat) {
-                /*
-                 * Disable the compatibility mode interrupts (8259 style),
-                 * needs IN/OUT support enabled.
-                 */
-                printk(KERN_INFO
-                       "%s: Disabling PC-AT compatible 8259 interrupts\n",
-                       __func__);
-                outb(0xff, 0xA1);
-                outb(0xff, 0x21);
-        }
+        if (pcat_compat)
+                iosapic_pcat_compat_init();
 }
 
 static inline int
diff --git a/arch/ia64/kernel/paravirt.c b/arch/ia64/kernel/paravirt.c
index 5daf659ff291..65c211b2f985 100644
--- a/arch/ia64/kernel/paravirt.c
+++ b/arch/ia64/kernel/paravirt.c
@@ -312,3 +312,28 @@ paravirt_cpu_asm_init(const struct pv_cpu_asm_switch *cpu_asm_switch)
                 cpu_asm_switch->work_processed_syscall;
         paravirt_leave_kernel_targ = cpu_asm_switch->leave_kernel;
 }
+
+/***************************************************************************
+ * pv_iosapic_ops
+ * iosapic read/write hooks.
+ */
+
+static unsigned int
+ia64_native_iosapic_read(char __iomem *iosapic, unsigned int reg)
+{
+        return __ia64_native_iosapic_read(iosapic, reg);
+}
+
+static void
+ia64_native_iosapic_write(char __iomem *iosapic, unsigned int reg, u32 val)
+{
+        __ia64_native_iosapic_write(iosapic, reg, val);
+}
+
+struct pv_iosapic_ops pv_iosapic_ops = {
+        .pcat_compat_init = ia64_native_iosapic_pcat_compat_init,
+        .get_irq_chip = ia64_native_iosapic_get_irq_chip,
+
+        .__read = ia64_native_iosapic_read,
+        .__write = ia64_native_iosapic_write,
+};
diff --git a/include/asm-ia64/iosapic.h b/include/asm-ia64/iosapic.h
index a3a4288daae8..b9c102e15f22 100644
--- a/include/asm-ia64/iosapic.h
+++ b/include/asm-ia64/iosapic.h
@@ -55,13 +55,27 @@
 
 #define NR_IOSAPICS                     256
 
-static inline unsigned int __iosapic_read(char __iomem *iosapic, unsigned int reg)
+#ifdef CONFIG_PARAVIRT_GUEST
+#include <asm/paravirt.h>
+#else
+#define iosapic_pcat_compat_init        ia64_native_iosapic_pcat_compat_init
+#define __iosapic_read                  __ia64_native_iosapic_read
+#define __iosapic_write                 __ia64_native_iosapic_write
+#define iosapic_get_irq_chip            ia64_native_iosapic_get_irq_chip
+#endif
+
+extern void __init ia64_native_iosapic_pcat_compat_init(void);
+extern struct irq_chip *ia64_native_iosapic_get_irq_chip(unsigned long trigger);
+
+static inline unsigned int
+__ia64_native_iosapic_read(char __iomem *iosapic, unsigned int reg)
 {
         writel(reg, iosapic + IOSAPIC_REG_SELECT);
         return readl(iosapic + IOSAPIC_WINDOW);
 }
 
-static inline void __iosapic_write(char __iomem *iosapic, unsigned int reg, u32 val)
+static inline void
+__ia64_native_iosapic_write(char __iomem *iosapic, unsigned int reg, u32 val)
 {
         writel(reg, iosapic + IOSAPIC_REG_SELECT);
         writel(val, iosapic + IOSAPIC_WINDOW);
diff --git a/include/asm-ia64/paravirt.h b/include/asm-ia64/paravirt.h
index 84d74c32eb98..3a40f624e86e 100644
--- a/include/asm-ia64/paravirt.h
+++ b/include/asm-ia64/paravirt.h
@@ -112,6 +112,46 @@ static inline void paravirt_post_smp_prepare_boot_cpu(void)
                 pv_init_ops.post_smp_prepare_boot_cpu();
 }
 
+/******************************************************************************
+ * replacement of iosapic operations.
+ */
+
+struct pv_iosapic_ops {
+        void (*pcat_compat_init)(void);
+
+        struct irq_chip *(*get_irq_chip)(unsigned long trigger);
+
+        unsigned int (*__read)(char __iomem *iosapic, unsigned int reg);
+        void (*__write)(char __iomem *iosapic, unsigned int reg, u32 val);
+};
+
+extern struct pv_iosapic_ops pv_iosapic_ops;
+
+static inline void
+iosapic_pcat_compat_init(void)
+{
+        if (pv_iosapic_ops.pcat_compat_init)
+                pv_iosapic_ops.pcat_compat_init();
+}
+
+static inline struct irq_chip*
+iosapic_get_irq_chip(unsigned long trigger)
+{
+        return pv_iosapic_ops.get_irq_chip(trigger);
+}
+
+static inline unsigned int
+__iosapic_read(char __iomem *iosapic, unsigned int reg)
+{
+        return pv_iosapic_ops.__read(iosapic, reg);
+}
+
+static inline void
+__iosapic_write(char __iomem *iosapic, unsigned int reg, u32 val)
+{
+        return pv_iosapic_ops.__write(iosapic, reg, val);
+}
+
 #endif /* !__ASSEMBLY__ */
 
 #else