From 8cfc3fd2954380afdea0590b359a665102ea7ef3 Mon Sep 17 00:00:00 2001 From: Achin Gupta Date: Mon, 9 Mar 2015 21:54:40 +0000 Subject: [PATCH] Set group status of PPIs and SGIs correctly on GICv3 systems On a GICv2 system, the group status of PPIs and SGIs is set in the GICD_IGROUPR0 register. On a GICv3 system, if affinity routing is enabled for the non-secure state, then the group status of PPIs and SGIs should be set in the GICR_IGROUPR0 register. ARM Trusted firmware sets the group status using the GICv2 sequence. On a GICv3 system, if the group status of an interrupt is set to Group 1 through a write to the GICD_IGROUPR0, then the GICR_IGROUPR0 is updated as well. The current sequence is incorrect since it first marks all PPIs and SGIs as Group 1. It then clears the bits in GICD_IGROUPR0 corresponding to secure interrupts to set their group status to Group 0. This operation is a no-op. It leaves the secure generic timer interrupt (#29) used by the TSP marked as Group 1. This causes the interrupt to interfere with the execution of non-secure software. Once an interrupt has been marked as Group 1, the GICR_IGROUPR0 should be programmed to change its group status. This patch rectifies this issue by setting the group status of only the non-secure PPI and SGIs to Group 1 in the first place. GICD_IGROUPR0 resets to 0. So secure interrupts are marked as Group 0 by default. Change-Id: I958b4b15f3e2b2444ce4c17764def36216498d00 --- drivers/arm/gic/arm_gic.c | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-) diff --git a/drivers/arm/gic/arm_gic.c b/drivers/arm/gic/arm_gic.c index 58fbc89a7..2888e719f 100644 --- a/drivers/arm/gic/arm_gic.c +++ b/drivers/arm/gic/arm_gic.c @@ -219,13 +219,10 @@ void arm_gic_cpuif_deactivate(void) ******************************************************************************/ void arm_gic_pcpu_distif_setup(void) { - unsigned int index, irq_num; + unsigned int index, irq_num, sec_ppi_sgi_mask; assert(g_gicd_base); - /* Mark all 32 SGI+PPI interrupts as Group 1 (non-secure) */ - gicd_write_igroupr(g_gicd_base, 0, ~0); - /* Setup PPI priorities doing four at a time */ for (index = 0; index < 32; index += 4) { gicd_write_ipriorityr(g_gicd_base, index, @@ -233,16 +230,25 @@ void arm_gic_pcpu_distif_setup(void) } assert(g_irq_sec_ptr); + sec_ppi_sgi_mask = 0; for (index = 0; index < g_num_irqs; index++) { irq_num = g_irq_sec_ptr[index]; if (irq_num < MIN_SPI_ID) { - /* We have an SGI or a PPI */ - gicd_clr_igroupr(g_gicd_base, irq_num); + /* We have an SGI or a PPI. They are Group0 at reset */ + sec_ppi_sgi_mask |= 1U << irq_num; gicd_set_ipriorityr(g_gicd_base, irq_num, GIC_HIGHEST_SEC_PRIORITY); gicd_set_isenabler(g_gicd_base, irq_num); } } + + /* + * Invert the bitmask to create a mask for non-secure PPIs and + * SGIs. Program the GICD_IGROUPR0 with this bit mask. This write will + * update the GICR_IGROUPR0 as well in case we are running on a GICv3 + * system. This is critical if GICD_CTLR.ARE_NS=1. + */ + gicd_write_igroupr(g_gicd_base, 0, ~sec_ppi_sgi_mask); } /*******************************************************************************