[PATCH V8] ACPI, PCI, irq: support IRQ numbers greater than 256

From: Sinan Kaya
Date: Thu Dec 03 2015 - 13:59:18 EST


The ACPI compiler uses the extended format when used interrupt numbers
are greater than 15. The extended IRQ is 32 bits according to the ACPI
spec. The code supports parsing the extended interrupt numbers. However,
due to used data structure type; the code silently truncates interrupt
numbers greater than 256.

First, this patch changes the interrupt number type to 32 bits. Next, the
penalty array has been limited to 16 for ISA IRQs. Finally, a new penalty
linklist has been added for all other interrupts greater than 16. If an IRQ
is not found in the link list, an IRQ info structure will be dynamically
allocated on the first access and will be placed on the list for further
reuse. The list will grow by the number of supported interrupts in the
ACPI table rather than having a 256 hard limitation.

Signed-off-by: Sinan Kaya <okaya@xxxxxxxxxxxxxx>
---
drivers/acpi/pci_link.c | 134 +++++++++++++++++++++++++++++++++++++-----------
1 file changed, 104 insertions(+), 30 deletions(-)

diff --git a/drivers/acpi/pci_link.c b/drivers/acpi/pci_link.c
index 7c8408b..e10661f 100644
--- a/drivers/acpi/pci_link.c
+++ b/drivers/acpi/pci_link.c
@@ -4,6 +4,7 @@
* Copyright (C) 2001, 2002 Andy Grover <andrew.grover@xxxxxxxxx>
* Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@xxxxxxxxx>
* Copyright (C) 2002 Dominik Brodowski <devel@xxxxxxxx>
+ * Copyright (c) 2015, The Linux Foundation. All rights reserved.
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*
@@ -67,12 +68,12 @@ static struct acpi_scan_handler pci_link_handler = {
* later even the link is disable. Instead, we just repick the active irq
*/
struct acpi_pci_link_irq {
- u8 active; /* Current IRQ */
+ u32 active; /* Current IRQ */
u8 triggering; /* All IRQs */
u8 polarity; /* All IRQs */
u8 resource_type;
u8 possible_count;
- u8 possible[ACPI_PCI_LINK_MAX_POSSIBLE];
+ u32 possible[ACPI_PCI_LINK_MAX_POSSIBLE];
u8 initialized:1;
u8 reserved:7;
};
@@ -437,8 +438,7 @@ static int acpi_pci_link_set(struct acpi_pci_link *link, int irq)
* enabled system.
*/

-#define ACPI_MAX_IRQS 256
-#define ACPI_MAX_ISA_IRQ 16
+ #define ACPI_MAX_ISA_IRQ 16

#define PIRQ_PENALTY_PCI_AVAILABLE (0)
#define PIRQ_PENALTY_PCI_POSSIBLE (16*16)
@@ -447,7 +447,7 @@ static int acpi_pci_link_set(struct acpi_pci_link *link, int irq)
#define PIRQ_PENALTY_ISA_USED (16*16*16*16*16)
#define PIRQ_PENALTY_ISA_ALWAYS (16*16*16*16*16*16)

-static int acpi_irq_penalty[ACPI_MAX_IRQS] = {
+static int acpi_irq_isa_penalty[ACPI_MAX_ISA_IRQ] = {
PIRQ_PENALTY_ISA_ALWAYS, /* IRQ0 timer */
PIRQ_PENALTY_ISA_ALWAYS, /* IRQ1 keyboard */
PIRQ_PENALTY_ISA_ALWAYS, /* IRQ2 cascade */
@@ -464,9 +464,61 @@ static int acpi_irq_penalty[ACPI_MAX_IRQS] = {
PIRQ_PENALTY_ISA_USED, /* IRQ13 fpe, sometimes */
PIRQ_PENALTY_ISA_USED, /* IRQ14 ide0 */
PIRQ_PENALTY_ISA_USED, /* IRQ15 ide1 */
- /* >IRQ15 */
};

+struct irq_penalty_info {
+ unsigned int irq;
+ int penalty;
+ struct list_head node;
+};
+
+LIST_HEAD(acpi_irq_penalty_list);
+
+static int acpi_irq_get_penalty(int irq)
+{
+ struct irq_penalty_info *irq_info;
+
+ if (irq < ACPI_MAX_ISA_IRQ)
+ return acpi_irq_isa_penalty[irq];
+
+ list_for_each_entry(irq_info, &acpi_irq_penalty_list, node) {
+ if (irq_info->irq == irq)
+ return irq_info->penalty;
+ }
+
+ return 0;
+}
+
+static int acpi_irq_set_penalty(int irq, unsigned int new_penalty)
+{
+ struct irq_penalty_info *irq_info;
+
+ /* see if this is a ISA IRQ */
+ if (irq < ACPI_MAX_ISA_IRQ) {
+ acpi_irq_isa_penalty[irq] = new_penalty;
+ return 0;
+ }
+
+ /* next, try to locate from the dynamic list */
+ list_for_each_entry(irq_info, &acpi_irq_penalty_list, node) {
+ if (irq_info->irq == irq) {
+ irq_info->penalty = new_penalty;
+ return 0;
+ }
+ }
+
+ /* nope, let's allocate a slot for this IRQ */
+ irq_info = kzalloc(sizeof(*irq_info), GFP_KERNEL);
+ if (!irq_info)
+ return -ENOMEM;
+
+ irq_info->irq = irq;
+ irq_info->penalty = new_penalty;
+ list_add_tail(&irq_info->node, &acpi_irq_penalty_list);
+
+ return 0;
+}
+
int __init acpi_irq_penalty_init(void)
{
struct acpi_pci_link *link;
@@ -487,15 +539,22 @@ int __init acpi_irq_penalty_init(void)
link->irq.possible_count;

for (i = 0; i < link->irq.possible_count; i++) {
- if (link->irq.possible[i] < ACPI_MAX_ISA_IRQ)
- acpi_irq_penalty[link->irq.
- possible[i]] +=
- penalty;
+ if (link->irq.possible[i] < ACPI_MAX_ISA_IRQ) {
+ int irqpos = link->irq.possible[i];
+ int curpen;
+
+ curpen = acpi_irq_get_penalty(irqpos);
+ curpen += penalty;
+ acpi_irq_set_penalty(irqpos, curpen);
+ }
}

} else if (link->irq.active) {
- acpi_irq_penalty[link->irq.active] +=
- PIRQ_PENALTY_PCI_POSSIBLE;
+ int curpen;
+
+ curpen = acpi_irq_get_penalty(link->irq.active);
+ curpen += PIRQ_PENALTY_PCI_POSSIBLE;
+ acpi_irq_set_penalty(link->irq.active, curpen);
}
}

@@ -547,12 +606,12 @@ static int acpi_pci_link_allocate(struct acpi_pci_link *link)
* the use of IRQs 9, 10, 11, and >15.
*/
for (i = (link->irq.possible_count - 1); i >= 0; i--) {
- if (acpi_irq_penalty[irq] >
- acpi_irq_penalty[link->irq.possible[i]])
+ if (acpi_irq_get_penalty(irq) >
+ acpi_irq_get_penalty(link->irq.possible[i]))
irq = link->irq.possible[i];
}
}
- if (acpi_irq_penalty[irq] >= PIRQ_PENALTY_ISA_ALWAYS) {
+ if (acpi_irq_get_penalty(irq) >= PIRQ_PENALTY_ISA_ALWAYS) {
printk(KERN_ERR PREFIX "No IRQ available for %s [%s]. "
"Try pci=noacpi or acpi=off\n",
acpi_device_name(link->device),
@@ -568,7 +627,12 @@ static int acpi_pci_link_allocate(struct acpi_pci_link *link)
acpi_device_bid(link->device));
return -ENODEV;
} else {
- acpi_irq_penalty[link->irq.active] += PIRQ_PENALTY_PCI_USING;
+ int curpen;
+
+ curpen = acpi_irq_get_penalty(link->irq.active);
+ curpen += PIRQ_PENALTY_PCI_USING;
+ acpi_irq_set_penalty(link->irq.active, curpen);
+
printk(KERN_WARNING PREFIX "%s [%s] enabled at IRQ %d\n",
acpi_device_name(link->device),
acpi_device_bid(link->device), link->irq.active);
@@ -778,7 +842,7 @@ static void acpi_pci_link_remove(struct acpi_device *device)
}

/*
- * modify acpi_irq_penalty[] from cmdline
+ * modify penalty from cmdline
*/
static int __init acpi_irq_penalty_update(char *str, int used)
{
@@ -796,13 +860,15 @@ static int __init acpi_irq_penalty_update(char *str, int used)
if (irq < 0)
continue;

- if (irq >= ARRAY_SIZE(acpi_irq_penalty))
- continue;
+ if (used) {
+ int curpen;

- if (used)
- acpi_irq_penalty[irq] += PIRQ_PENALTY_ISA_USED;
+ curpen = acpi_irq_get_penalty(irq);
+ curpen += PIRQ_PENALTY_ISA_USED;
+ acpi_irq_set_penalty(irq, curpen);
+ }
else
- acpi_irq_penalty[irq] = PIRQ_PENALTY_PCI_AVAILABLE;
+ acpi_irq_set_penalty(irq, PIRQ_PENALTY_PCI_AVAILABLE);

if (retval != 2) /* no next number */
break;
@@ -819,18 +885,22 @@ static int __init acpi_irq_penalty_update(char *str, int used)
*/
void acpi_penalize_isa_irq(int irq, int active)
{
- if (irq >= 0 && irq < ARRAY_SIZE(acpi_irq_penalty)) {
+ if (irq >= 0) {
+ int curpen;
+
+ curpen = acpi_irq_get_penalty(irq);
if (active)
- acpi_irq_penalty[irq] += PIRQ_PENALTY_ISA_USED;
+ curpen += PIRQ_PENALTY_ISA_USED;
else
- acpi_irq_penalty[irq] += PIRQ_PENALTY_PCI_USING;
+ curpen += PIRQ_PENALTY_PCI_USING;
+ acpi_irq_set_penalty(irq, curpen);
}
}

bool acpi_isa_irq_available(int irq)
{
- return irq >= 0 && (irq >= ARRAY_SIZE(acpi_irq_penalty) ||
- acpi_irq_penalty[irq] < PIRQ_PENALTY_ISA_ALWAYS);
+ return irq >= 0 &&
+ (acpi_irq_get_penalty(irq) < PIRQ_PENALTY_ISA_ALWAYS);
}

/*
@@ -840,12 +910,16 @@ bool acpi_isa_irq_available(int irq)
*/
void acpi_penalize_sci_irq(int irq, int trigger, int polarity)
{
- if (irq >= 0 && irq < ARRAY_SIZE(acpi_irq_penalty)) {
+ if (irq >= 0) {
+ int curpen;
+
+ curpen = acpi_irq_get_penalty(irq);
if (trigger != ACPI_MADT_TRIGGER_LEVEL ||
polarity != ACPI_MADT_POLARITY_ACTIVE_LOW)
- acpi_irq_penalty[irq] += PIRQ_PENALTY_ISA_ALWAYS;
+ curpen += PIRQ_PENALTY_ISA_ALWAYS;
else
- acpi_irq_penalty[irq] += PIRQ_PENALTY_PCI_USING;
+ curpen += PIRQ_PENALTY_PCI_USING;
+ acpi_irq_set_penalty(irq, curpen);
}
}

--
Qualcomm Technologies, Inc. on behalf of Qualcomm Innovation Center, Inc.
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project

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