Re:[PATCH]2.6.3-rc2 MSI Support for IA64

From: long
Date: Fri Feb 27 2004 - 17:48:20 EST

After receiving all inputs from Linux Community, we made some changes to
the patch. Attached is an update version.

Thanks,
Long

----------------------------------------------------------------------------
diff -urN linux-2.6.3-rc2/arch/ia64/Kconfig linux-2.6.3-rc2-MSI/arch/ia64/Kconfig
--- linux-2.6.3-rc2/arch/ia64/Kconfig 2004-02-09 22:01:16.000000000 -0500
+++ linux-2.6.3-rc2-MSI/arch/ia64/Kconfig 2004-02-26 16:31:03.908765998 -0500
@@ -433,6 +433,18 @@
information about which PCI hardware does work under Linux and which
doesn't.

+config PCI_USE_VECTOR
+ bool "Message Signaled Interrupt (MSI) Support"
+ default n
+ help
+ This enables MSI, Message Signaled Interrupt, on specific
+ MSI capable device functions detected upon requests from the
+ device drivers. Message Signal Interrupt enables an MSI-capable
+ hardware device to send an inbound Memory Write on its PCI bus
+ instead of asserting IRQ signal on device IRQ pin.
+
+ If you don't know what to do here, say N.
+
config PCI_DOMAINS
bool
default PCI
diff -urN linux-2.6.3-rc2/arch/ia64/kernel/irq_ia64.c linux-2.6.3-rc2-MSI/arch/ia64/kernel/irq_ia64.c
--- linux-2.6.3-rc2/arch/ia64/kernel/irq_ia64.c 2004-02-09 22:00:36.000000000 -0500
+++ linux-2.6.3-rc2-MSI/arch/ia64/kernel/irq_ia64.c 2004-02-26 16:31:03.909742561 -0500
@@ -60,12 +60,18 @@
int
ia64_alloc_vector (void)
{
+#ifdef CONFIG_PCI_USE_VECTOR
+ extern int assign_irq_vector(int irq);
+
+ return assign_irq_vector(AUTO_ASSIGN);
+#else
static int next_vector = IA64_FIRST_DEVICE_VECTOR;

if (next_vector > IA64_LAST_DEVICE_VECTOR)
/* XXX could look for sharable vectors instead of panic'ing... */
panic("ia64_alloc_vector: out of interrupt vectors!");
return next_vector++;
+#endif
}

extern unsigned int do_IRQ(unsigned long irq, struct pt_regs *regs);
diff -urN linux-2.6.3-rc2/drivers/pci/msi.c linux-2.6.3-rc2-MSI/drivers/pci/msi.c
--- linux-2.6.3-rc2/drivers/pci/msi.c 2004-02-09 22:01:16.000000000 -0500
+++ linux-2.6.3-rc2-MSI/drivers/pci/msi.c 2004-02-26 16:33:14.605053460 -0500
@@ -1,5 +1,8 @@
/*
- * linux/drivers/pci/msi.c
+ * Purpose: PCI Message Signaled Interrupt (MSI)
+ *
+ * Copyright (C) 2003-2004 Intel
+ * Copyright (C) Tom Long Nguyen (tom.l.nguyen@xxxxxxxxx)
*/

#include <linux/mm.h>
@@ -15,13 +18,10 @@
#include <asm/errno.h>
#include <asm/io.h>
#include <asm/smp.h>
-#include <asm/desc.h>
-#include <asm/io_apic.h>
-#include <mach_apic.h>

+static void set_msi_affinity(unsigned int vector, cpumask_t cpu_mask);
#include "msi.h"

-
static spinlock_t msi_lock = SPIN_LOCK_UNLOCKED;
static struct msi_desc* msi_desc[NR_IRQS] = { [0 ... NR_IRQS-1] = NULL };
static kmem_cache_t* msi_cachep;
@@ -92,7 +92,6 @@
{
struct msi_desc *entry;
struct msg_address address;
- unsigned int dest_id;

entry = (struct msi_desc *)msi_desc[vector];
if (!entry || !entry->dev)
@@ -109,10 +108,9 @@
entry->dev->bus->ops->read(entry->dev->bus, entry->dev->devfn,
msi_lower_address_reg(pos), 4,
&address.lo_address.value);
- dest_id = (address.lo_address.u.dest_id &
- MSI_ADDRESS_HEADER_MASK) |
- (cpu_mask_to_apicid(cpu_mask) << MSI_TARGET_CPU_SHIFT);
- address.lo_address.u.dest_id = dest_id;
+ address.lo_address.value &= MSI_ADDRESS_DEST_ID_MASK;
+ address.lo_address.value |= (cpu_mask_to_apicid(cpu_mask) <<
+ MSI_TARGET_CPU_SHIFT);
entry->msi_attrib.current_cpu = cpu_mask_to_apicid(cpu_mask);
entry->dev->bus->ops->write(entry->dev->bus, entry->dev->devfn,
msi_lower_address_reg(pos), 4,
@@ -125,10 +123,9 @@
PCI_MSIX_ENTRY_LOWER_ADDR_OFFSET;

address.lo_address.value = readl(entry->mask_base + offset);
- dest_id = (address.lo_address.u.dest_id &
- MSI_ADDRESS_HEADER_MASK) |
- (cpu_mask_to_apicid(cpu_mask) << MSI_TARGET_CPU_SHIFT);
- address.lo_address.u.dest_id = dest_id;
+ address.lo_address.value &= MSI_ADDRESS_DEST_ID_MASK;
+ address.lo_address.value |= (cpu_mask_to_apicid(cpu_mask) <<
+ MSI_TARGET_CPU_SHIFT);
entry->msi_attrib.current_cpu = cpu_mask_to_apicid(cpu_mask);
writel(address.lo_address.value, entry->mask_base + offset);
break;
@@ -137,14 +134,6 @@
break;
}
}
-
-static inline void move_msi(int vector)
-{
- if (!cpus_empty(pending_irq_balance_cpumask[vector])) {
- set_msi_affinity(vector, pending_irq_balance_cpumask[vector]);
- cpus_clear(pending_irq_balance_cpumask[vector]);
- }
-}
#endif

static void mask_MSI_irq(unsigned int vector)
@@ -259,11 +248,11 @@

memset(msi_address, 0, sizeof(struct msg_address));
msi_address->hi_address = (u32)0;
- dest_id = (MSI_ADDRESS_HEADER << MSI_ADDRESS_HEADER_SHIFT) |
- (MSI_TARGET_CPU << MSI_TARGET_CPU_SHIFT);
- msi_address->lo_address.u.dest_mode = MSI_LOGICAL_MODE;
+ dest_id = (MSI_ADDRESS_HEADER << MSI_ADDRESS_HEADER_SHIFT);
+ msi_address->lo_address.u.dest_mode = MSI_DEST_MODE;
msi_address->lo_address.u.redirection_hint = MSI_REDIRECTION_HINT_MODE;
msi_address->lo_address.u.dest_id = dest_id;
+ msi_address->lo_address.value |= (MSI_TARGET_CPU << MSI_TARGET_CPU_SHIFT);
}

static int pci_vector_resources(void)
@@ -271,18 +260,8 @@
static int res = -EINVAL;
int nr_free_vectors;

- if (res == -EINVAL) {
- int i, repeat;
- for (i = NR_REPEATS; i > 0; i--) {
- if ((FIRST_DEVICE_VECTOR + i * 8) > FIRST_SYSTEM_VECTOR)
- continue;
- break;
- }
- i++;
- repeat = (FIRST_SYSTEM_VECTOR - FIRST_DEVICE_VECTOR)/i;
- res = i * repeat - NR_RESERVED_VECTORS + 1;
- }
-
+ if (res == -EINVAL)
+ res = vector_resources();
nr_free_vectors = res + nr_released_vectors - nr_alloc_vectors;

return nr_free_vectors;
@@ -292,10 +271,10 @@
{
static int current_vector = FIRST_DEVICE_VECTOR, offset = 0;

- if (irq != MSI_AUTO && IO_APIC_VECTOR(irq) > 0)
+ if (irq != AUTO_ASSIGN && IO_APIC_VECTOR(irq) > 0)
return IO_APIC_VECTOR(irq);
next:
- current_vector += 8;
+ current_vector += VECTOR_STEP;
if (current_vector == SYSCALL_VECTOR)
goto next;

@@ -308,7 +287,7 @@
return -ENOSPC;

vector_irq[current_vector] = irq;
- if (irq != MSI_AUTO)
+ if (irq != AUTO_ASSIGN)
IO_APIC_VECTOR(irq) = current_vector;

nr_alloc_vectors++;
@@ -358,10 +337,9 @@
return -EBUSY;
}

- vector = assign_irq_vector(MSI_AUTO);
+ vector = assign_irq_vector(AUTO_ASSIGN);
if (vector == (FIRST_SYSTEM_VECTOR - 8))
new_vector_avail = 0;
-
spin_unlock_irqrestore(&msi_lock, flags);
return vector;
}
diff -urN linux-2.6.3-rc2/drivers/pci/msi.h linux-2.6.3-rc2-MSI/drivers/pci/msi.h
--- linux-2.6.3-rc2/drivers/pci/msi.h 2004-02-09 22:01:04.000000000 -0500
+++ linux-2.6.3-rc2-MSI/drivers/pci/msi.h 2004-02-26 16:32:56.028881812 -0500
@@ -1,12 +1,38 @@
/*
- * msi.h
+ *
+ * Copyright (C) 2003-2004 Intel
+ * Copyright (C) Tom Long Nguyen (tom.l.nguyen@xxxxxxxxx)
*
*/

#ifndef MSI_H
#define MSI_H

-#define MSI_AUTO -1
+#ifndef CONFIG_IA64
+#include <asm/desc.h>
+#ifndef CONFIG_X86_64
+#include <mach_apic.h>
+#endif
+#define VECTOR_STEP 8
+#else
+#define FIRST_DEVICE_VECTOR IA64_FIRST_DEVICE_VECTOR
+#define FIRST_SYSTEM_VECTOR (IA64_LAST_DEVICE_VECTOR + 8)
+#define VECTOR_STEP 1
+static inline void set_intr_gate (int nr, void *func) {}
+#define IO_APIC_VECTOR(irq) (irq)
+#define ack_APIC_irq ia64_eoi
+#define irq_desc _irq_desc
+#define cpu_mask_to_apicid(mask) cpu_physical_id(first_cpu(mask))
+#endif
+
+#if !defined(AUTO_ASSIGN)
+#define AUTO_ASSIGN -1
+#endif
+
+#if !defined(SYSCALL_VECTOR)
+#define SYSCALL_VECTOR 0x80
+#endif
+
#define NR_REPEATS 23
#define NR_RESERVED_VECTORS 3 /*FIRST_DEVICE_VECTOR,FIRST_SYSTEM_VECTOR,0x80 */

@@ -28,15 +54,43 @@
#define set_msi_irq_affinity set_msi_affinity
#else
#define set_msi_irq_affinity NULL
+#endif
+
+#if defined(CONFIG_SMP) && !defined(CONFIG_IA64)
+static inline void move_msi(int vector)
+{
+ if (!cpus_empty(pending_irq_balance_cpumask[vector])) {
+ set_msi_affinity(vector, pending_irq_balance_cpumask[vector]);
+ cpus_clear(pending_irq_balance_cpumask[vector]);
+ }
+}
+#else
static inline void move_msi(int vector) {}
#endif

#ifndef CONFIG_X86_IO_APIC
static inline int get_ioapic_vector(struct pci_dev *dev) { return -1;}
-static inline void restore_ioapic_irq_handler(int irq) {}
+#endif
+
+static inline int vector_resources(void)
+{
+ int res;
+#ifndef CONFIG_IA64
+ int i, repeat;
+ for (i = NR_REPEATS; i > 0; i--) {
+ if ((FIRST_DEVICE_VECTOR + i * 8) > FIRST_SYSTEM_VECTOR)
+ continue;
+ break;
+ }
+ i++;
+ repeat = (FIRST_SYSTEM_VECTOR - FIRST_DEVICE_VECTOR)/i;
+ res = i * repeat - NR_RESERVED_VECTORS + 1;
#else
-extern void restore_ioapic_irq_handler(int irq);
+ res = FIRST_SYSTEM_VECTOR - FIRST_DEVICE_VECTOR - 8;
#endif
+
+ return res;
+}

/*
* MSI-X Address Register
@@ -80,25 +134,34 @@
#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_TARGET_CPU_SHIFT 4
+#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
+
+#ifdef CONFIG_IA64
+#define MSI_DEST_MODE MSI_PHYSICAL_MODE
+#define MSI_TARGET_CPU ((ia64_getreg(_IA64_REG_CR_LID) >> 16) & 0xffff)
+#define MSI_TARGET_CPU_SHIFT 4
+#else
+#define MSI_DEST_MODE MSI_LOGICAL_MODE
+#define MSI_TARGET_CPU_SHIFT 12
#ifdef CONFIG_SMP
#define MSI_TARGET_CPU logical_smp_processor_id()
#else
#define MSI_TARGET_CPU TARGET_CPUS
#endif
+#endif

struct msg_data {
#if defined(__LITTLE_ENDIAN_BITFIELD)
diff -urN linux-2.6.3-rc2/include/asm-ia64/hw_irq.h linux-2.6.3-rc2-MSI/include/asm-ia64/hw_irq.h
--- linux-2.6.3-rc2/include/asm-ia64/hw_irq.h 2004-02-09 22:00:44.000000000 -0500
+++ linux-2.6.3-rc2-MSI/include/asm-ia64/hw_irq.h 2004-02-26 16:31:03.937086310 -0500
@@ -34,6 +34,8 @@
#define IA64_MAX_VECTORED_IRQ 255
#define IA64_NUM_VECTORS 256

+#define AUTO_ASSIGN -1
+
#define IA64_SPURIOUS_INT_VECTOR 0x0f

/*
-
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