Re: [boot-wrapper PATCH v2 6/8] gic-v3: Prepare for gicv3 with EL2
From: Andre Przywara <andre.przywara@arm.com>
Date: 2021-05-24 18:55:32
On Fri, 21 May 2021 18:48:05 +0800 Jaxson Han [off-list ref] wrote: Hi,
This is a preparation for allowing boot-wrapper configuring the gicv3 with EL2. When confiuring with EL2, since there is no ICC_CTLR_EL2, the ICC_CTLR_EL3 cannot be replaced with ICC_CTLR_EL2 simply. See [https://developer.arm.com/documentation/ihi0069/latest/]. As the caller, gic_secure_init expects the ICC_CTLR to be written, we change the function into gic_init_icc_ctlr(). In the GIC spec, the r/w bits in this register ([6:0]) either affect EL3 IRQ routing (not applicable since no EL3), non-secure IRQ handling (not applicable since only secure state in Armv8-R aarch64), or are aliased to ICC_CTLR_EL1 bits. So, based on this, the new gic_init_icc_ctlr() would be: When currentEL is EL3, init ICC_CTLR_EL3 as before. When currentEL is not EL3, init ICC_CTLR_EL1 with ICC_CTLR_EL1_RESET.
Looks good, thanks!
Signed-off-by: Jaxson Han <redacted>
Reviewed-by: Andre Przywara <andre.przywara@arm.com> Cheers, Andre
quoted hunk ↗ jump to hunk
--- arch/aarch32/include/asm/gic-v3.h | 7 ++++++ arch/aarch64/include/asm/gic-v3.h | 38 ++++++++++++++++++++++++++++--- gic-v3.c | 2 +- 3 files changed, 43 insertions(+), 4 deletions(-)diff --git a/arch/aarch32/include/asm/gic-v3.h b/arch/aarch32/include/asm/gic-v3.h index ec9a327..86abe09 100644 --- a/arch/aarch32/include/asm/gic-v3.h +++ b/arch/aarch32/include/asm/gic-v3.h@@ -9,6 +9,8 @@ #ifndef __ASM_AARCH32_GICV3_H #define __ASM_AARCH32_GICV3_H +#define ICC_CTLR_RESET (0UL) + static inline uint32_t gic_read_icc_sre(void) { uint32_t val;@@ -26,4 +28,9 @@ static inline void gic_write_icc_ctlr(uint32_t val) asm volatile ("mcr p15, 6, %0, c12, c12, 4" : : "r" (val)); } +static inline void gic_init_icc_ctlr() +{ + gic_write_icc_ctlr(ICC_CTLR_RESET); +} + #endifdiff --git a/arch/aarch64/include/asm/gic-v3.h b/arch/aarch64/include/asm/gic-v3.h index e743c02..b3dfbd3 100644 --- a/arch/aarch64/include/asm/gic-v3.h +++ b/arch/aarch64/include/asm/gic-v3.h@@ -15,21 +15,53 @@ #define ICC_CTLR_EL3 "S3_6_C12_C12_4" #define ICC_PMR_EL1 "S3_0_C4_C6_0" +#define ICC_CTLR_EL3_RESET (0UL) +#define ICC_CTLR_EL1_RESET (0UL) + +static inline uint32_t current_el(void) +{ + uint32_t val; + + asm volatile ("mrs %0, CurrentEL" : "=r" (val)); + return val; +} + static inline uint32_t gic_read_icc_sre(void) { uint32_t val; - asm volatile ("mrs %0, " ICC_SRE_EL3 : "=r" (val)); + + if(current_el() == CURRENTEL_EL3) + asm volatile ("mrs %0, " ICC_SRE_EL3 : "=r" (val)); + else + asm volatile ("mrs %0, " ICC_SRE_EL2 : "=r" (val)); + return val; } static inline void gic_write_icc_sre(uint32_t val) { - asm volatile ("msr " ICC_SRE_EL3 ", %0" : : "r" (val)); + if(current_el() == CURRENTEL_EL3) + asm volatile ("msr " ICC_SRE_EL3 ", %0" : : "r" (val)); + else + asm volatile ("msr " ICC_SRE_EL2 ", %0" : : "r" (val)); } -static inline void gic_write_icc_ctlr(uint32_t val) +static inline void gic_write_icc_ctlr_el3(uint32_t val) { asm volatile ("msr " ICC_CTLR_EL3 ", %0" : : "r" (val)); } +static inline void gic_write_icc_ctlr_el1(uint32_t val) +{ + asm volatile ("msr " ICC_CTLR_EL1 ", %0" : : "r" (val)); +} + +static inline void gic_init_icc_ctlr() +{ + if(current_el() == CURRENTEL_EL3) + gic_write_icc_ctlr_el3(ICC_CTLR_EL3_RESET); + else + gic_write_icc_ctlr_el1(ICC_CTLR_EL1_RESET); +} + #endifdiff --git a/gic-v3.c b/gic-v3.c index ae2d2bc..4850572 100644 --- a/gic-v3.c +++ b/gic-v3.c@@ -121,6 +121,6 @@ void gic_secure_init(void) gic_write_icc_sre(sre); isb(); - gic_write_icc_ctlr(0); + gic_init_icc_ctlr(); isb(); }
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