diff options
| -rw-r--r-- | arch/arc/include/asm/irqflags-arcv2.h | 7 | ||||
| -rw-r--r-- | arch/arc/kernel/intc-arcv2.c | 41 |
2 files changed, 29 insertions, 19 deletions
diff --git a/arch/arc/include/asm/irqflags-arcv2.h b/arch/arc/include/asm/irqflags-arcv2.h index 258b0e5ad332..1fc18ee06cf2 100644 --- a/arch/arc/include/asm/irqflags-arcv2.h +++ b/arch/arc/include/asm/irqflags-arcv2.h @@ -30,8 +30,11 @@ /* Was Intr taken in User Mode */ #define AUX_IRQ_ACT_BIT_U 31 -/* 0 is highest level, but taken by FIRQs, if present in design */ -#define ARCV2_IRQ_DEF_PRIO 0 +/* + * User space should be interruptable even by lowest prio interrupt + * Safe even if actual interrupt priorities is fewer or even one + */ +#define ARCV2_IRQ_DEF_PRIO 15 /* seed value for status register */ #define ISA_INIT_STATUS_BITS (STATUS_IE_MASK | STATUS_AD_MASK | \ diff --git a/arch/arc/kernel/intc-arcv2.c b/arch/arc/kernel/intc-arcv2.c index 0394f9f61b46..942526322ae7 100644 --- a/arch/arc/kernel/intc-arcv2.c +++ b/arch/arc/kernel/intc-arcv2.c @@ -14,6 +14,8 @@ #include <linux/irqchip.h> #include <asm/irq.h> +static int irq_prio; + /* * Early Hardware specific Interrupt setup * -Called very early (start_kernel -> setup_arch -> setup_processor) @@ -24,6 +26,14 @@ void arc_init_IRQ(void) { unsigned int tmp; + struct irq_build { +#ifdef CONFIG_CPU_BIG_ENDIAN + unsigned int pad:3, firq:1, prio:4, exts:8, irqs:8, ver:8; +#else + unsigned int ver:8, irqs:8, exts:8, prio:4, firq:1, pad:3; +#endif + } irq_bcr; + struct aux_irq_ctrl { #ifdef CONFIG_CPU_BIG_ENDIAN unsigned int res3:18, save_idx_regs:1, res2:1, @@ -46,28 +56,25 @@ void arc_init_IRQ(void) WRITE_AUX(AUX_IRQ_CTRL, ictrl); - /* setup status32, don't enable intr yet as kernel doesn't want */ - tmp = read_aux_reg(0xa); - tmp |= ISA_INIT_STATUS_BITS; - tmp &= ~STATUS_IE_MASK; - asm volatile("flag %0 \n"::"r"(tmp)); - /* * ARCv2 core intc provides multiple interrupt priorities (upto 16). * Typical builds though have only two levels (0-high, 1-low) * Linux by default uses lower prio 1 for most irqs, reserving 0 for * NMI style interrupts in future (say perf) - * - * Read the intc BCR to confirm that Linux default priority is avail - * in h/w - * - * Note: - * IRQ_BCR[27..24] contains N-1 (for N priority levels) and prio level - * is 0 based. */ - tmp = (read_aux_reg(ARC_REG_IRQ_BCR) >> 24 ) & 0xF; - if (ARCV2_IRQ_DEF_PRIO > tmp) - panic("Linux default irq prio incorrect\n"); + + READ_BCR(ARC_REG_IRQ_BCR, irq_bcr); + + irq_prio = irq_bcr.prio; /* Encoded as N-1 for N levels */ + pr_info("archs-intc\t: %d priority levels (default %d)%s\n", + irq_prio + 1, irq_prio, + irq_bcr.firq ? " FIRQ (not used)":""); + + /* setup status32, don't enable intr yet as kernel doesn't want */ + tmp = read_aux_reg(0xa); + tmp |= STATUS_AD_MASK | (irq_prio << 1); + tmp &= ~STATUS_IE_MASK; + asm volatile("flag %0 \n"::"r"(tmp)); } static void arcv2_irq_mask(struct irq_data *data) @@ -86,7 +93,7 @@ void arcv2_irq_enable(struct irq_data *data) { /* set default priority */ write_aux_reg(AUX_IRQ_SELECT, data->irq); - write_aux_reg(AUX_IRQ_PRIORITY, ARCV2_IRQ_DEF_PRIO); + write_aux_reg(AUX_IRQ_PRIORITY, irq_prio); /* * hw auto enables (linux unmask) all by default |