mirror of
https://github.com/openwrt/openwrt.git
synced 2024-12-22 15:02:32 +00:00
f791fb4af4
Signed-off-by: Felix Fietkau <nbd@nbd.name> Signed-off-by: Tim Harvey <tharvey@gateworks.com> [fixes]
117 lines
2.8 KiB
Diff
117 lines
2.8 KiB
Diff
From: Matt Redfearn <matt.redfearn@imgtec.com>
|
|
Date: Mon, 19 Dec 2016 14:20:59 +0000
|
|
Subject: [PATCH] MIPS: Switch to the irq_stack in interrupts
|
|
|
|
When enterring interrupt context via handle_int or except_vec_vi, switch
|
|
to the irq_stack of the current CPU if it is not already in use.
|
|
|
|
The current stack pointer is masked with the thread size and compared to
|
|
the base or the irq stack. If it does not match then the stack pointer
|
|
is set to the top of that stack, otherwise this is a nested irq being
|
|
handled on the irq stack so the stack pointer should be left as it was.
|
|
|
|
The in-use stack pointer is placed in the callee saved register s1. It
|
|
will be saved to the stack when plat_irq_dispatch is invoked and can be
|
|
restored once control returns here.
|
|
|
|
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
|
|
---
|
|
|
|
--- a/arch/mips/kernel/genex.S
|
|
+++ b/arch/mips/kernel/genex.S
|
|
@@ -187,9 +187,44 @@ NESTED(handle_int, PT_SIZE, sp)
|
|
|
|
LONG_L s0, TI_REGS($28)
|
|
LONG_S sp, TI_REGS($28)
|
|
- PTR_LA ra, ret_from_irq
|
|
- PTR_LA v0, plat_irq_dispatch
|
|
- jr v0
|
|
+
|
|
+ /*
|
|
+ * SAVE_ALL ensures we are using a valid kernel stack for the thread.
|
|
+ * Check if we are already using the IRQ stack.
|
|
+ */
|
|
+ move s1, sp # Preserve the sp
|
|
+
|
|
+ /* Get IRQ stack for this CPU */
|
|
+ ASM_CPUID_MFC0 k0, ASM_SMP_CPUID_REG
|
|
+#if defined(CONFIG_32BIT) || defined(KBUILD_64BIT_SYM32)
|
|
+ lui k1, %hi(irq_stack)
|
|
+#else
|
|
+ lui k1, %highest(irq_stack)
|
|
+ daddiu k1, %higher(irq_stack)
|
|
+ dsll k1, 16
|
|
+ daddiu k1, %hi(irq_stack)
|
|
+ dsll k1, 16
|
|
+#endif
|
|
+ LONG_SRL k0, SMP_CPUID_PTRSHIFT
|
|
+ LONG_ADDU k1, k0
|
|
+ LONG_L t0, %lo(irq_stack)(k1)
|
|
+
|
|
+ # Check if already on IRQ stack
|
|
+ PTR_LI t1, ~(_THREAD_SIZE-1)
|
|
+ and t1, t1, sp
|
|
+ beq t0, t1, 2f
|
|
+
|
|
+ /* Switch to IRQ stack */
|
|
+ li t1, _IRQ_STACK_SIZE
|
|
+ PTR_ADD sp, t0, t1
|
|
+
|
|
+2:
|
|
+ jal plat_irq_dispatch
|
|
+
|
|
+ /* Restore sp */
|
|
+ move sp, s1
|
|
+
|
|
+ j ret_from_irq
|
|
#ifdef CONFIG_CPU_MICROMIPS
|
|
nop
|
|
#endif
|
|
@@ -262,8 +297,44 @@ NESTED(except_vec_vi_handler, 0, sp)
|
|
|
|
LONG_L s0, TI_REGS($28)
|
|
LONG_S sp, TI_REGS($28)
|
|
- PTR_LA ra, ret_from_irq
|
|
- jr v0
|
|
+
|
|
+ /*
|
|
+ * SAVE_ALL ensures we are using a valid kernel stack for the thread.
|
|
+ * Check if we are already using the IRQ stack.
|
|
+ */
|
|
+ move s1, sp # Preserve the sp
|
|
+
|
|
+ /* Get IRQ stack for this CPU */
|
|
+ ASM_CPUID_MFC0 k0, ASM_SMP_CPUID_REG
|
|
+#if defined(CONFIG_32BIT) || defined(KBUILD_64BIT_SYM32)
|
|
+ lui k1, %hi(irq_stack)
|
|
+#else
|
|
+ lui k1, %highest(irq_stack)
|
|
+ daddiu k1, %higher(irq_stack)
|
|
+ dsll k1, 16
|
|
+ daddiu k1, %hi(irq_stack)
|
|
+ dsll k1, 16
|
|
+#endif
|
|
+ LONG_SRL k0, SMP_CPUID_PTRSHIFT
|
|
+ LONG_ADDU k1, k0
|
|
+ LONG_L t0, %lo(irq_stack)(k1)
|
|
+
|
|
+ # Check if already on IRQ stack
|
|
+ PTR_LI t1, ~(_THREAD_SIZE-1)
|
|
+ and t1, t1, sp
|
|
+ beq t0, t1, 2f
|
|
+
|
|
+ /* Switch to IRQ stack */
|
|
+ li t1, _IRQ_STACK_SIZE
|
|
+ PTR_ADD sp, t0, t1
|
|
+
|
|
+2:
|
|
+ jal plat_irq_dispatch
|
|
+
|
|
+ /* Restore sp */
|
|
+ move sp, s1
|
|
+
|
|
+ j ret_from_irq
|
|
END(except_vec_vi_handler)
|
|
|
|
/*
|