The patch below does not apply to the 4.14-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 6d4d367d0e9ffab4d64a3436256a6a052dc1195d Mon Sep 17 00:00:00 2001

From: Paul Burton paul.burton@mips.com Date: Wed, 5 Jun 2019 09:34:10 +0100 Subject: [PATCH] irqchip/mips-gic: Use the correct local interrupt map registers

The MIPS GIC contains a block of registers used to map local interrupts to a particular CPU interrupt pin. Since these registers are found at a consecutive range of addresses we access them using an index, via the (read|write)_gic_v[lo]_map accessor functions. We currently use values from enum mips_gic_local_interrupt as those indices.

Unfortunately whilst enum mips_gic_local_interrupt provides the correct offsets for bits in the pending & mask registers, the ordering of the map registers is subtly different... Compared with the ordering of pending & mask bits, the map registers move the FDC from the end of the list to index 3 after the timer interrupt. As a result the performance counter & software interrupts are therefore at indices 4-6 rather than indices 3-5.

Notably this causes problems with performance counter interrupts being incorrectly mapped on some systems, and presumably will also cause problems for FDC interrupts.

Introduce a function to map from enum mips_gic_local_interrupt to the index of the corresponding map register, and use it to ensure we access the map registers for the correct interrupts.

Signed-off-by: Paul Burton paul.burton@mips.com Fixes: a0dc5cb5e31b ("irqchip: mips-gic: Simplify gic_local_irq_domain_map()") Fixes: da61fcf9d62a ("irqchip: mips-gic: Use irq_cpu_online to (un)mask all-VP(E) IRQs") Reported-and-tested-by: Archer Yan ayan@wavecomp.com Cc: Thomas Gleixner tglx@linutronix.de Cc: Jason Cooper jason@lakedaemon.net Cc: stable@vger.kernel.org # v4.14+ Signed-off-by: Marc Zyngier marc.zyngier@arm.com

diff --git a/arch/mips/include/asm/mips-gic.h b/arch/mips/include/asm/mips-gic.h index 558059a8f218..0277b56157af 100644 --- a/arch/mips/include/asm/mips-gic.h +++ b/arch/mips/include/asm/mips-gic.h @@ -314,6 +314,36 @@ static inline bool mips_gic_present(void) return IS_ENABLED(CONFIG_MIPS_GIC) && mips_gic_base; }

+/** + * mips_gic_vx_map_reg() - Return GIC_Vx_<intr>_MAP register offset + * @intr: A GIC local interrupt + * + * Determine the index of the GIC_VL_<intr>_MAP or GIC_VO_<intr>_MAP register + * within the block of GIC map registers. This is almost the same as the order + * of interrupts in the pending & mask registers, as used by enum + * mips_gic_local_interrupt, but moves the FDC interrupt & thus offsets the + * interrupts after it... + * + * Return: The map register index corresponding to @intr. + * + * The return value is suitable for use with the (read|write)_gic_v[lo]_map + * accessor functions. + */ +static inline unsigned int +mips_gic_vx_map_reg(enum mips_gic_local_interrupt intr) +{ + /* WD, Compare & Timer are 1:1 */ + if (intr <= GIC_LOCAL_INT_TIMER) + return intr; + + /* FDC moves to after Timer... */ + if (intr == GIC_LOCAL_INT_FDC) + return GIC_LOCAL_INT_TIMER + 1; + + /* As a result everything else is offset by 1 */ + return intr + 1; +} + /** * gic_get_c0_compare_int() - Return cp0 count/compare interrupt virq * diff --git a/drivers/irqchip/irq-mips-gic.c b/drivers/irqchip/irq-mips-gic.c index d32268cc1174..f3985469c221 100644 --- a/drivers/irqchip/irq-mips-gic.c +++ b/drivers/irqchip/irq-mips-gic.c @@ -388,7 +388,7 @@ static void gic_all_vpes_irq_cpu_online(struct irq_data *d) intr = GIC_HWIRQ_TO_LOCAL(d->hwirq); cd = irq_data_get_irq_chip_data(d);

- write_gic_vl_map(intr, cd->map); + write_gic_vl_map(mips_gic_vx_map_reg(intr), cd->map); if (cd->mask) write_gic_vl_smask(BIT(intr)); } @@ -517,7 +517,7 @@ static int gic_irq_domain_map(struct irq_domain *d, unsigned int virq, spin_lock_irqsave(&gic_lock, flags); for_each_online_cpu(cpu) { write_gic_vl_other(mips_cm_vp_id(cpu)); - write_gic_vo_map(intr, map); + write_gic_vo_map(mips_gic_vx_map_reg(intr), map); } spin_unlock_irqrestore(&gic_lock, flags);