[PATCH] PCI: msi abstractions and support for altix

Abstract portions of the MSI core for platforms that do not use standard
APIC interrupt controllers.  This is implemented through a new arch-specific
msi setup routine, and a set of msi ops which can be set on a per platform
basis.
Signed-off-by: Mark Maule <maule@sgi.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/pci/Makefile

@@ -26,7 +26,11 @@ obj-$(CONFIG_PPC32) += setup-irq.o
 obj-$(CONFIG_PPC64) += setup-bus.o
 obj-$(CONFIG_MIPS) += setup-bus.o setup-irq.o
 obj-$(CONFIG_X86_VISWS) += setup-irq.o
-obj-$(CONFIG_PCI_MSI) += msi.o
+
+msiobj-y := msi.o msi-apic.o
+msiobj-$(CONFIG_IA64_GENERIC) += msi-altix.o
+msiobj-$(CONFIG_IA64_SGI_SN2) += msi-altix.o
+obj-$(CONFIG_PCI_MSI) += $(msiobj-y)
 
 #
 # ACPI Related PCI FW Functions

drivers/pci/msi-altix.c

+/*
+ * 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.
+ *
+ * Copyright (C) 2006 Silicon Graphics, Inc.  All Rights Reserved.
+ */
+
+#include <asm/errno.h>
+
+int
+sn_msi_init(void)
+{
+	/*
+	 * return error until MSI is supported on altix platforms
+	 */
+	return -EINVAL;
+}

drivers/pci/msi-apic.c

+/*
+ * MSI hooks for standard x86 apic
+ */
+
+#include <linux/pci.h>
+#include <linux/irq.h>
+
+#include "msi.h"
+
+/*
+ * Shifts for APIC-based data
+ */
+
+#define MSI_DATA_VECTOR_SHIFT		0
+#define	    MSI_DATA_VECTOR(v)		(((u8)v) << MSI_DATA_VECTOR_SHIFT)
+
+#define MSI_DATA_DELIVERY_SHIFT		8
+#define     MSI_DATA_DELIVERY_FIXED	(0 << MSI_DATA_DELIVERY_SHIFT)
+#define     MSI_DATA_DELIVERY_LOWPRI	(1 << MSI_DATA_DELIVERY_SHIFT)
+
+#define MSI_DATA_LEVEL_SHIFT		14
+#define     MSI_DATA_LEVEL_DEASSERT	(0 << MSI_DATA_LEVEL_SHIFT)
+#define     MSI_DATA_LEVEL_ASSERT	(1 << MSI_DATA_LEVEL_SHIFT)
+
+#define MSI_DATA_TRIGGER_SHIFT		15
+#define     MSI_DATA_TRIGGER_EDGE	(0 << MSI_DATA_TRIGGER_SHIFT)
+#define     MSI_DATA_TRIGGER_LEVEL	(1 << MSI_DATA_TRIGGER_SHIFT)
+
+/*
+ * Shift/mask fields for APIC-based bus address
+ */
+
+#define MSI_ADDR_HEADER			0xfee00000
+
+#define MSI_ADDR_DESTID_MASK		0xfff0000f
+#define     MSI_ADDR_DESTID_CPU(cpu)	((cpu) << MSI_TARGET_CPU_SHIFT)
+
+#define MSI_ADDR_DESTMODE_SHIFT		2
+#define     MSI_ADDR_DESTMODE_PHYS	(0 << MSI_ADDR_DESTMODE_SHIFT)
+#define	    MSI_ADDR_DESTMODE_LOGIC	(1 << MSI_ADDR_DESTMODE_SHIFT)
+
+#define MSI_ADDR_REDIRECTION_SHIFT	3
+#define     MSI_ADDR_REDIRECTION_CPU	(0 << MSI_ADDR_REDIRECTION_SHIFT)
+#define     MSI_ADDR_REDIRECTION_LOWPRI	(1 << MSI_ADDR_REDIRECTION_SHIFT)
+
+
+static void
+msi_target_apic(unsigned int vector,
+		unsigned int dest_cpu,
+		u32 *address_hi,	/* in/out */
+		u32 *address_lo)	/* in/out */
+{
+	u32 addr = *address_lo;
+
+	addr &= MSI_ADDR_DESTID_MASK;
+	addr |= MSI_ADDR_DESTID_CPU(cpu_physical_id(dest_cpu));
+
+	*address_lo = addr;
+}
+
+static int
+msi_setup_apic(struct pci_dev *pdev,	/* unused in generic */
+		unsigned int vector,
+		u32 *address_hi,
+		u32 *address_lo,
+		u32 *data)
+{
+	unsigned long	dest_phys_id;
+
+	dest_phys_id = cpu_physical_id(first_cpu(cpu_online_map));
+
+	*address_hi = 0;
+	*address_lo =	MSI_ADDR_HEADER |
+			MSI_ADDR_DESTMODE_PHYS |
+			MSI_ADDR_REDIRECTION_CPU |
+			MSI_ADDR_DESTID_CPU(dest_phys_id);
+
+	*data = MSI_DATA_TRIGGER_EDGE |
+		MSI_DATA_LEVEL_ASSERT |
+		MSI_DATA_DELIVERY_FIXED |
+		MSI_DATA_VECTOR(vector);
+
+	return 0;
+}
+
+static void
+msi_teardown_apic(unsigned int vector)
+{
+	return;		/* no-op */
+}
+
+/*
+ * Generic ops used on most IA archs/platforms.  Set with msi_register()
+ */
+
+struct msi_ops msi_apic_ops = {
+	.setup = msi_setup_apic,
+	.teardown = msi_teardown_apic,
+	.target = msi_target_apic,
+};

drivers/pci/msi.h

@@ -6,6 +6,68 @@
 #ifndef MSI_H
 #define MSI_H
 
+/*
+ * MSI operation vector.  Used by the msi core code (drivers/pci/msi.c)
+ * to abstract platform-specific tasks relating to MSI address generation
+ * and resource management.
+ */
+struct msi_ops {
+	/**
+	 * setup - generate an MSI bus address and data for a given vector
+	 * @pdev: PCI device context (in)
+	 * @vector: vector allocated by the msi core (in)
+	 * @addr_hi: upper 32 bits of PCI bus MSI address (out)
+	 * @addr_lo: lower 32 bits of PCI bus MSI address (out)
+	 * @data: MSI data payload (out)
+	 *
+	 * Description: The setup op is used to generate a PCI bus addres and
+	 * data which the msi core will program into the card MSI capability
+	 * registers.  The setup routine is responsible for picking an initial
+	 * cpu to target the MSI at.  The setup routine is responsible for
+	 * examining pdev to determine the MSI capabilities of the card and
+	 * generating a suitable address/data.  The setup routine is
+	 * responsible for allocating and tracking any system resources it
+	 * needs to route the MSI to the cpu it picks, and for associating
+	 * those resources with the passed in vector.
+	 *
+	 * Returns 0 if the MSI address/data was successfully setup.
+	 **/
+
+	int	(*setup)    (struct pci_dev *pdev, unsigned int vector,
+			     u32 *addr_hi, u32 *addr_lo, u32 *data);
+
+	/**
+	 * teardown - release resources allocated by setup
+	 * @vector: vector context for resources (in)
+	 *
+	 * Description:  The teardown op is used to release any resources
+	 * that were allocated in the setup routine associated with the passed
+	 * in vector.
+	 **/
+
+	void	(*teardown) (unsigned int vector);
+
+	/**
+	 * target - retarget an MSI at a different cpu
+	 * @vector: vector context for resources (in)
+	 * @cpu:  new cpu to direct vector at (in)
+	 * @addr_hi: new value of PCI bus upper 32 bits (in/out)
+	 * @addr_lo: new value of PCI bus lower 32 bits (in/out)
+	 *
+	 * Description:  The target op is used to redirect an MSI vector
+	 * at a different cpu.  addr_hi/addr_lo coming in are the existing
+	 * values that the MSI core has programmed into the card.  The
+	 * target code is responsible for freeing any resources (if any)
+	 * associated with the old address, and generating a new PCI bus
+	 * addr_hi/addr_lo that will redirect the vector at the indicated cpu.
+	 **/
+
+	void	(*target)   (unsigned int vector, unsigned int cpu,
+			     u32 *addr_hi, u32 *addr_lo);
+};
+
+extern int msi_register(struct msi_ops *ops);
+
 #include <asm/msi.h>
 
 /*
@@ -63,67 +125,6 @@ extern int pci_vector_resources(int last, int nr_released);
 #define msix_mask(address)		(address | PCI_MSIX_FLAGS_BITMASK)
 #define msix_is_pending(address) 	(address & PCI_MSIX_FLAGS_PENDMASK)
 
-/*
- * MSI Defined Data Structures
- */
-#define MSI_ADDRESS_HEADER		0xfee
-#define MSI_ADDRESS_HEADER_SHIFT	12
-#define MSI_ADDRESS_HEADER_MASK		0xfff000
-#define MSI_ADDRESS_DEST_ID_MASK	0xfff0000f
-#define MSI_TARGET_CPU_MASK		0xff
-#define MSI_DELIVERY_MODE		0
-#define MSI_LEVEL_MODE			1	/* Edge always assert */
-#define MSI_TRIGGER_MODE		0	/* MSI is edge sensitive */
-#define MSI_PHYSICAL_MODE		0
-#define MSI_LOGICAL_MODE		1
-#define MSI_REDIRECTION_HINT_MODE	0
-
-struct msg_data {
-#if defined(__LITTLE_ENDIAN_BITFIELD)
-	__u32	vector		:  8;
-	__u32	delivery_mode	:  3;	/* 000b: FIXED | 001b: lowest prior */
-	__u32	reserved_1	:  3;
-	__u32	level		:  1;	/* 0: deassert | 1: assert */
-	__u32	trigger		:  1;	/* 0: edge | 1: level */
-	__u32	reserved_2	: 16;
-#elif defined(__BIG_ENDIAN_BITFIELD)
-	__u32	reserved_2	: 16;
-	__u32	trigger		:  1;	/* 0: edge | 1: level */
-	__u32	level		:  1;	/* 0: deassert | 1: assert */
-	__u32	reserved_1	:  3;
-	__u32	delivery_mode	:  3;	/* 000b: FIXED | 001b: lowest prior */
-	__u32	vector		:  8;
-#else
-#error "Bitfield endianness not defined! Check your byteorder.h"
-#endif
-} __attribute__ ((packed));
-
-struct msg_address {
-	union {
-		struct {
-#if defined(__LITTLE_ENDIAN_BITFIELD)
-			__u32	reserved_1	:  2;
-			__u32	dest_mode	:  1;	/*0:physic | 1:logic */
-			__u32	redirection_hint:  1;  	/*0: dedicated CPU
-							  1: lowest priority */
-			__u32	reserved_2	:  4;
- 			__u32	dest_id		: 24;	/* Destination ID */
-#elif defined(__BIG_ENDIAN_BITFIELD)
- 			__u32	dest_id		: 24;	/* Destination ID */
-			__u32	reserved_2	:  4;
-			__u32	redirection_hint:  1;  	/*0: dedicated CPU
-							  1: lowest priority */
-			__u32	dest_mode	:  1;	/*0:physic | 1:logic */
-			__u32	reserved_1	:  2;
-#else
-#error "Bitfield endianness not defined! Check your byteorder.h"
-#endif
-      		}u;
-       		__u32  value;
-	}lo_address;
-	__u32 	hi_address;
-} __attribute__ ((packed));
-
 struct msi_desc {
 	struct {
 		__u8	type	: 5; 	/* {0: unused, 5h:MSI, 11h:MSI-X} */
@@ -132,7 +133,7 @@ struct msi_desc {
 		__u8	reserved: 1; 	/* reserved			  */
 		__u8	entry_nr;    	/* specific enabled entry 	  */
 		__u8	default_vector; /* default pre-assigned vector    */
-		__u8	current_cpu; 	/* current destination cpu	  */
+		__u8	unused; 	/* formerly unused destination cpu*/
 	}msi_attrib;
 
 	struct {
@@ -142,6 +143,14 @@ struct msi_desc {
 
 	void __iomem *mask_base;
 	struct pci_dev *dev;
+
+#ifdef CONFIG_PM
+	/* PM save area for MSIX address/data */
+
+	u32	address_hi_save;
+	u32	address_lo_save;
+	u32	data_save;
+#endif
 };
 
 #endif /* MSI_H */

include/asm-i386/msi.h

@@ -12,4 +12,12 @@
 #define LAST_DEVICE_VECTOR		232
 #define MSI_TARGET_CPU_SHIFT	12
 
+extern struct msi_ops msi_apic_ops;
+
+static inline int msi_arch_init(void)
+{
+	msi_register(&msi_apic_ops);
+	return 0;
+}
+
 #endif /* ASM_MSI_H */

include/asm-ia64/machvec.h

@@ -75,6 +75,7 @@ typedef unsigned char ia64_mv_readb_relaxed_t (const volatile void __iomem *);
 typedef unsigned short ia64_mv_readw_relaxed_t (const volatile void __iomem *);
 typedef unsigned int ia64_mv_readl_relaxed_t (const volatile void __iomem *);
 typedef unsigned long ia64_mv_readq_relaxed_t (const volatile void __iomem *);
+typedef int ia64_mv_msi_init_t (void);
 
 static inline void
 machvec_noop (void)
@@ -153,6 +154,7 @@ extern void machvec_tlb_migrate_finish (struct mm_struct *);
 #  define platform_readl_relaxed        ia64_mv.readl_relaxed
 #  define platform_readq_relaxed        ia64_mv.readq_relaxed
 #  define platform_migrate		ia64_mv.migrate
+#  define platform_msi_init		ia64_mv.msi_init
 # endif
 
 /* __attribute__((__aligned__(16))) is required to make size of the
@@ -202,6 +204,7 @@ struct ia64_machine_vector {
 	ia64_mv_readl_relaxed_t *readl_relaxed;
 	ia64_mv_readq_relaxed_t *readq_relaxed;
 	ia64_mv_migrate_t *migrate;
+	ia64_mv_msi_init_t *msi_init;
 } __attribute__((__aligned__(16))); /* align attrib? see above comment */
 
 #define MACHVEC_INIT(name)			\
@@ -247,6 +250,7 @@ struct ia64_machine_vector {
 	platform_readl_relaxed,			\
 	platform_readq_relaxed,			\
 	platform_migrate,			\
+	platform_msi_init,			\
 }
 
 extern struct ia64_machine_vector ia64_mv;
@@ -400,5 +404,8 @@ extern int ia64_pci_legacy_write(struct pci_bus *bus, u16 port, u32 val, u8 size
 #ifndef platform_migrate
 # define platform_migrate machvec_noop_task
 #endif
+#ifndef platform_msi_init
+# define platform_msi_init	((ia64_mv_msi_init_t*)NULL)
+#endif
 
 #endif /* _ASM_IA64_MACHVEC_H */

include/asm-ia64/machvec_sn2.h

@@ -67,6 +67,8 @@ extern ia64_mv_dma_sync_sg_for_device	sn_dma_sync_sg_for_device;
 extern ia64_mv_dma_mapping_error	sn_dma_mapping_error;
 extern ia64_mv_dma_supported		sn_dma_supported;
 extern ia64_mv_migrate_t		sn_migrate;
+extern ia64_mv_msi_init_t		sn_msi_init;
+
 
 /*
  * This stuff has dual use!
@@ -117,6 +119,11 @@ extern ia64_mv_migrate_t		sn_migrate;
 #define platform_dma_mapping_error		sn_dma_mapping_error
 #define platform_dma_supported		sn_dma_supported
 #define platform_migrate		sn_migrate
+#ifdef CONFIG_PCI_MSI
+#define platform_msi_init		sn_msi_init
+#else
+#define platform_msi_init		((ia64_mv_msi_init_t*)NULL)
+#endif
 
 #include <asm/sn/io.h>
 

include/asm-ia64/msi.h

@@ -14,4 +14,16 @@ static inline void set_intr_gate (int nr, void *func) {}
 #define ack_APIC_irq		ia64_eoi
 #define MSI_TARGET_CPU_SHIFT	4
 
+extern struct msi_ops msi_apic_ops;
+
+static inline int msi_arch_init(void)
+{
+	if (platform_msi_init)
+		return platform_msi_init();
+
+	/* default ops for most ia64 platforms */
+	msi_register(&msi_apic_ops);
+	return 0;
+}
+
 #endif /* ASM_MSI_H */

include/asm-x86_64/msi.h

@@ -13,4 +13,12 @@
 #define LAST_DEVICE_VECTOR		232
 #define MSI_TARGET_CPU_SHIFT	12
 
+extern struct msi_ops msi_apic_ops;
+
+static inline int msi_arch_init(void)
+{
+	msi_register(&msi_apic_ops);
+	return 0;
+}
+
 #endif /* ASM_MSI_H */