From 13b7ea6377fb23f02784a38e894f8fad49816376 Mon Sep 17 00:00:00 2001 From: Markos Chandras Date: Wed, 30 Oct 2013 14:27:48 +0000 Subject: [PATCH] MIPS: malta: Fix GIC interrupt offsets The GIC interrupt offsets are calculated based on the value of NR_CPUS. However, this is wrong because NR_CPUS may or may not contain the real number of the actual cpus present in the system. We fix that by using the 'nr_cpu_ids' variable which contains the real number of cpus in the system. Previously, an MT core (eg with 8 VPEs) will fail to boot if NR_CPUS was > 8 with the following errors: ------------[ cut here ]------------ WARNING: CPU: 0 PID: 0 at kernel/irq/chip.c:670 __irq_set_handler+0x15c/0x164() Modules linked in: CPU: 0 PID: 0 Comm: swapper/0 Tainted: G W 3.12.0-rc5-00087-gced5633 5 Stack : 00000006 00000004 00000000 00000000 00000000 00000000 807a4f36 00000053 807a0000 00000000 80173218 80565aa8 00000000 00000000 00000000 0000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 0000000 00000000 00000000 00000000 8054fd00 8054fd94 80500514 805657a7 8016eb4 807a0000 80500514 00000000 00000000 80565aa8 8079a5d8 80565766 8054fd0 ... Call Trace: [<801098c0>] show_stack+0x64/0x7c [<8049c6b0>] dump_stack+0x64/0x84 [<8012efc4>] warn_slowpath_common+0x84/0xb4 [<8012f00c>] warn_slowpath_null+0x18/0x24 [<80173218>] __irq_set_handler+0x15c/0x164 [<80587cf4>] arch_init_ipiirq+0x2c/0x3c [<805880c8>] arch_init_irq+0x3c4/0x4bc [<80588e28>] init_IRQ+0x3c/0x50 [<805847e8>] start_kernel+0x230/0x3d8 ---[ end trace 4eaa2a86a8e2da26 ]--- This is now fixed and the Malta board can boot with any NR_CPUS value which also helps supporting more processors in a single kernel binary. Signed-off-by: Markos Chandras Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/6091/ Signed-off-by: Ralf Baechle --- arch/mips/mti-malta/malta-int.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/arch/mips/mti-malta/malta-int.c b/arch/mips/mti-malta/malta-int.c index c69da37..5b28e81 100644 --- a/arch/mips/mti-malta/malta-int.c +++ b/arch/mips/mti-malta/malta-int.c @@ -473,7 +473,7 @@ static void __init fill_ipi_map(void) { int cpu; - for (cpu = 0; cpu < NR_CPUS; cpu++) { + for (cpu = 0; cpu < nr_cpu_ids; cpu++) { fill_ipi_map1(gic_resched_int_base, cpu, GIC_CPU_INT1); fill_ipi_map1(gic_call_int_base, cpu, GIC_CPU_INT2); } @@ -574,8 +574,9 @@ void __init arch_init_irq(void) /* FIXME */ int i; #if defined(CONFIG_MIPS_MT_SMP) - gic_call_int_base = GIC_NUM_INTRS - NR_CPUS; - gic_resched_int_base = gic_call_int_base - NR_CPUS; + gic_call_int_base = GIC_NUM_INTRS - + (NR_CPUS - nr_cpu_ids) * 2 - nr_cpu_ids; + gic_resched_int_base = gic_call_int_base - nr_cpu_ids; fill_ipi_map(); #endif gic_init(GIC_BASE_ADDR, GIC_ADDRSPACE_SZ, gic_intr_map, @@ -599,7 +600,7 @@ void __init arch_init_irq(void) printk("CPU%d: status register now %08x\n", smp_processor_id(), read_c0_status()); write_c0_status(0x1100dc00); printk("CPU%d: status register frc %08x\n", smp_processor_id(), read_c0_status()); - for (i = 0; i < NR_CPUS; i++) { + for (i = 0; i < nr_cpu_ids; i++) { arch_init_ipiirq(MIPS_GIC_IRQ_BASE + GIC_RESCHED_INT(i), &irq_resched); arch_init_ipiirq(MIPS_GIC_IRQ_BASE + -- 2.7.4