diff options
author | Peter Maydell <peter.maydell@linaro.org> | 2022-05-12 16:14:55 +0100 |
---|---|---|
committer | Peter Maydell <peter.maydell@linaro.org> | 2022-05-19 16:19:02 +0100 |
commit | 84597ff39484ec171567c7c80061100eb4a6c331 (patch) | |
tree | 311535a3a332177387931e52885a89e32ecf59e6 /hw/intc | |
parent | 9774c0f7ba6ae2980a291cb53a13661ddaa2f5de (diff) |
hw/intc/arm_gicv3: Support configurable number of physical priority bits
The GICv3 code has always supported a configurable number of virtual
priority and preemption bits, but our implementation currently
hardcodes the number of physical priority bits at 8. This is not
what most hardware implementations provide; for instance the
Cortex-A53 provides only 5 bits of physical priority.
Make the number of physical priority/preemption bits driven by fields
in the GICv3CPUState, the way that we already do for virtual
priority/preemption bits. We set cs->pribits to 8, so there is no
behavioural change in this commit. A following commit will add the
machinery for CPUs to set this to the correct value for their
implementation.
Note that changing the number of priority bits would be a migration
compatibility break, because the semantics of the icc_apr[][] array
changes.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220512151457.3899052-5-peter.maydell@linaro.org
Message-id: 20220506162129.2896966-4-peter.maydell@linaro.org
Diffstat (limited to 'hw/intc')
-rw-r--r-- | hw/intc/arm_gicv3_cpuif.c | 182 |
1 files changed, 128 insertions, 54 deletions
diff --git a/hw/intc/arm_gicv3_cpuif.c b/hw/intc/arm_gicv3_cpuif.c index ebf269b73a..69a15f7a44 100644 --- a/hw/intc/arm_gicv3_cpuif.c +++ b/hw/intc/arm_gicv3_cpuif.c @@ -787,6 +787,36 @@ static uint64_t icv_iar_read(CPUARMState *env, const ARMCPRegInfo *ri) return intid; } +static uint32_t icc_fullprio_mask(GICv3CPUState *cs) +{ + /* + * Return a mask word which clears the unimplemented priority bits + * from a priority value for a physical interrupt. (Not to be confused + * with the group priority, whose mask depends on the value of BPR + * for the interrupt group.) + */ + return ~0U << (8 - cs->pribits); +} + +static inline int icc_min_bpr(GICv3CPUState *cs) +{ + /* The minimum BPR for the physical interface. */ + return 7 - cs->prebits; +} + +static inline int icc_min_bpr_ns(GICv3CPUState *cs) +{ + return icc_min_bpr(cs) + 1; +} + +static inline int icc_num_aprs(GICv3CPUState *cs) +{ + /* Return the number of APR registers (1, 2, or 4) */ + int aprmax = 1 << MAX(cs->prebits - 5, 0); + assert(aprmax <= ARRAY_SIZE(cs->icc_apr[0])); + return aprmax; +} + static int icc_highest_active_prio(GICv3CPUState *cs) { /* Calculate the current running priority based on the set bits @@ -794,14 +824,14 @@ static int icc_highest_active_prio(GICv3CPUState *cs) */ int i; - for (i = 0; i < ARRAY_SIZE(cs->icc_apr[0]); i++) { + for (i = 0; i < icc_num_aprs(cs); i++) { uint32_t apr = cs->icc_apr[GICV3_G0][i] | cs->icc_apr[GICV3_G1][i] | cs->icc_apr[GICV3_G1NS][i]; if (!apr) { continue; } - return (i * 32 + ctz32(apr)) << (GIC_MIN_BPR + 1); + return (i * 32 + ctz32(apr)) << (icc_min_bpr(cs) + 1); } /* No current active interrupts: return idle priority */ return 0xff; @@ -980,7 +1010,7 @@ static void icc_pmr_write(CPUARMState *env, const ARMCPRegInfo *ri, trace_gicv3_icc_pmr_write(gicv3_redist_affid(cs), value); - value &= 0xff; + value &= icc_fullprio_mask(cs); if (arm_feature(env, ARM_FEATURE_EL3) && !arm_is_secure(env) && (env->cp15.scr_el3 & SCR_FIQ)) { @@ -1004,7 +1034,7 @@ static void icc_activate_irq(GICv3CPUState *cs, int irq) */ uint32_t mask = icc_gprio_mask(cs, cs->hppi.grp); int prio = cs->hppi.prio & mask; - int aprbit = prio >> 1; + int aprbit = prio >> (8 - cs->prebits); int regno = aprbit / 32; int regbit = aprbit % 32; @@ -1162,7 +1192,7 @@ static void icc_drop_prio(GICv3CPUState *cs, int grp) */ int i; - for (i = 0; i < ARRAY_SIZE(cs->icc_apr[grp]); i++) { + for (i = 0; i < icc_num_aprs(cs); i++) { uint64_t *papr = &cs->icc_apr[grp][i]; if (!*papr) { @@ -1590,7 +1620,7 @@ static void icc_bpr_write(CPUARMState *env, const ARMCPRegInfo *ri, return; } - minval = (grp == GICV3_G1NS) ? GIC_MIN_BPR_NS : GIC_MIN_BPR; + minval = (grp == GICV3_G1NS) ? icc_min_bpr_ns(cs) : icc_min_bpr(cs); if (value < minval) { value = minval; } @@ -2171,19 +2201,19 @@ static void icc_reset(CPUARMState *env, const ARMCPRegInfo *ri) cs->icc_ctlr_el1[GICV3_S] = ICC_CTLR_EL1_A3V | (1 << ICC_CTLR_EL1_IDBITS_SHIFT) | - (7 << ICC_CTLR_EL1_PRIBITS_SHIFT); + ((cs->pribits - 1) << ICC_CTLR_EL1_PRIBITS_SHIFT); cs->icc_ctlr_el1[GICV3_NS] = ICC_CTLR_EL1_A3V | (1 << ICC_CTLR_EL1_IDBITS_SHIFT) | - (7 << ICC_CTLR_EL1_PRIBITS_SHIFT); + ((cs->pribits - 1) << ICC_CTLR_EL1_PRIBITS_SHIFT); cs->icc_pmr_el1 = 0; - cs->icc_bpr[GICV3_G0] = GIC_MIN_BPR; - cs->icc_bpr[GICV3_G1] = GIC_MIN_BPR; - cs->icc_bpr[GICV3_G1NS] = GIC_MIN_BPR_NS; + cs->icc_bpr[GICV3_G0] = icc_min_bpr(cs); + cs->icc_bpr[GICV3_G1] = icc_min_bpr(cs); + cs->icc_bpr[GICV3_G1NS] = icc_min_bpr_ns(cs); memset(cs->icc_apr, 0, sizeof(cs->icc_apr)); memset(cs->icc_igrpen, 0, sizeof(cs->icc_igrpen)); cs->icc_ctlr_el3 = ICC_CTLR_EL3_NDS | ICC_CTLR_EL3_A3V | (1 << ICC_CTLR_EL3_IDBITS_SHIFT) | - (7 << ICC_CTLR_EL3_PRIBITS_SHIFT); + ((cs->pribits - 1) << ICC_CTLR_EL3_PRIBITS_SHIFT); memset(cs->ich_apr, 0, sizeof(cs->ich_apr)); cs->ich_hcr_el2 = 0; @@ -2238,27 +2268,6 @@ static const ARMCPRegInfo gicv3_cpuif_reginfo[] = { .readfn = icc_ap_read, .writefn = icc_ap_write, }, - { .name = "ICC_AP0R1_EL1", .state = ARM_CP_STATE_BOTH, - .opc0 = 3, .opc1 = 0, .crn = 12, .crm = 8, .opc2 = 5, - .type = ARM_CP_IO | ARM_CP_NO_RAW, - .access = PL1_RW, .accessfn = gicv3_fiq_access, - .readfn = icc_ap_read, - .writefn = icc_ap_write, - }, - { .name = "ICC_AP0R2_EL1", .state = ARM_CP_STATE_BOTH, - .opc0 = 3, .opc1 = 0, .crn = 12, .crm = 8, .opc2 = 6, - .type = ARM_CP_IO | ARM_CP_NO_RAW, - .access = PL1_RW, .accessfn = gicv3_fiq_access, - .readfn = icc_ap_read, - .writefn = icc_ap_write, - }, - { .name = "ICC_AP0R3_EL1", .state = ARM_CP_STATE_BOTH, - .opc0 = 3, .opc1 = 0, .crn = 12, .crm = 8, .opc2 = 7, - .type = ARM_CP_IO | ARM_CP_NO_RAW, - .access = PL1_RW, .accessfn = gicv3_fiq_access, - .readfn = icc_ap_read, - .writefn = icc_ap_write, - }, /* All the ICC_AP1R*_EL1 registers are banked */ { .name = "ICC_AP1R0_EL1", .state = ARM_CP_STATE_BOTH, .opc0 = 3, .opc1 = 0, .crn = 12, .crm = 9, .opc2 = 0, @@ -2267,27 +2276,6 @@ static const ARMCPRegInfo gicv3_cpuif_reginfo[] = { .readfn = icc_ap_read, .writefn = icc_ap_write, }, - { .name = "ICC_AP1R1_EL1", .state = ARM_CP_STATE_BOTH, - .opc0 = 3, .opc1 = 0, .crn = 12, .crm = 9, .opc2 = 1, - .type = ARM_CP_IO | ARM_CP_NO_RAW, - .access = PL1_RW, .accessfn = gicv3_irq_access, - .readfn = icc_ap_read, - .writefn = icc_ap_write, - }, - { .name = "ICC_AP1R2_EL1", .state = ARM_CP_STATE_BOTH, - .opc0 = 3, .opc1 = 0, .crn = 12, .crm = 9, .opc2 = 2, - .type = ARM_CP_IO | ARM_CP_NO_RAW, - .access = PL1_RW, .accessfn = gicv3_irq_access, - .readfn = icc_ap_read, - .writefn = icc_ap_write, - }, - { .name = "ICC_AP1R3_EL1", .state = ARM_CP_STATE_BOTH, - .opc0 = 3, .opc1 = 0, .crn = 12, .crm = 9, .opc2 = 3, - .type = ARM_CP_IO | ARM_CP_NO_RAW, - .access = PL1_RW, .accessfn = gicv3_irq_access, - .readfn = icc_ap_read, - .writefn = icc_ap_write, - }, { .name = "ICC_DIR_EL1", .state = ARM_CP_STATE_BOTH, .opc0 = 3, .opc1 = 0, .crn = 12, .crm = 11, .opc2 = 1, .type = ARM_CP_IO | ARM_CP_NO_RAW, @@ -2430,6 +2418,54 @@ static const ARMCPRegInfo gicv3_cpuif_reginfo[] = { }, }; +static const ARMCPRegInfo gicv3_cpuif_icc_apxr1_reginfo[] = { + { .name = "ICC_AP0R1_EL1", .state = ARM_CP_STATE_BOTH, + .opc0 = 3, .opc1 = 0, .crn = 12, .crm = 8, .opc2 = 5, + .type = ARM_CP_IO | ARM_CP_NO_RAW, + .access = PL1_RW, .accessfn = gicv3_fiq_access, + .readfn = icc_ap_read, + .writefn = icc_ap_write, + }, + { .name = "ICC_AP1R1_EL1", .state = ARM_CP_STATE_BOTH, + .opc0 = 3, .opc1 = 0, .crn = 12, .crm = 9, .opc2 = 1, + .type = ARM_CP_IO | ARM_CP_NO_RAW, + .access = PL1_RW, .accessfn = gicv3_irq_access, + .readfn = icc_ap_read, + .writefn = icc_ap_write, + }, +}; + +static const ARMCPRegInfo gicv3_cpuif_icc_apxr23_reginfo[] = { + { .name = "ICC_AP0R2_EL1", .state = ARM_CP_STATE_BOTH, + .opc0 = 3, .opc1 = 0, .crn = 12, .crm = 8, .opc2 = 6, + .type = ARM_CP_IO | ARM_CP_NO_RAW, + .access = PL1_RW, .accessfn = gicv3_fiq_access, + .readfn = icc_ap_read, + .writefn = icc_ap_write, + }, + { .name = "ICC_AP0R3_EL1", .state = ARM_CP_STATE_BOTH, + .opc0 = 3, .opc1 = 0, .crn = 12, .crm = 8, .opc2 = 7, + .type = ARM_CP_IO | ARM_CP_NO_RAW, + .access = PL1_RW, .accessfn = gicv3_fiq_access, + .readfn = icc_ap_read, + .writefn = icc_ap_write, + }, + { .name = "ICC_AP1R2_EL1", .state = ARM_CP_STATE_BOTH, + .opc0 = 3, .opc1 = 0, .crn = 12, .crm = 9, .opc2 = 2, + .type = ARM_CP_IO | ARM_CP_NO_RAW, + .access = PL1_RW, .accessfn = gicv3_irq_access, + .readfn = icc_ap_read, + .writefn = icc_ap_write, + }, + { .name = "ICC_AP1R3_EL1", .state = ARM_CP_STATE_BOTH, + .opc0 = 3, .opc1 = 0, .crn = 12, .crm = 9, .opc2 = 3, + .type = ARM_CP_IO | ARM_CP_NO_RAW, + .access = PL1_RW, .accessfn = gicv3_irq_access, + .readfn = icc_ap_read, + .writefn = icc_ap_write, + }, +}; + static uint64_t ich_ap_read(CPUARMState *env, const ARMCPRegInfo *ri) { GICv3CPUState *cs = icc_cs_from_env(env); @@ -2772,6 +2808,44 @@ void gicv3_init_cpuif(GICv3State *s) * get back to the GICv3CPUState from the CPUARMState. */ define_arm_cp_regs(cpu, gicv3_cpuif_reginfo); + + /* + * For the moment, retain the existing behaviour of 8 priority bits; + * in a following commit we will take this from the CPU state, + * as we do for the virtual priority bits. + */ + cs->pribits = 8; + /* + * The GICv3 has separate ID register fields for virtual priority + * and preemption bit values, but only a single ID register field + * for the physical priority bits. The preemption bit count is + * always the same as the priority bit count, except that 8 bits + * of priority means 7 preemption bits. We precalculate the + * preemption bits because it simplifies the code and makes the + * parallels between the virtual and physical bits of the GIC + * a bit clearer. + */ + cs->prebits = cs->pribits; + if (cs->prebits == 8) { + cs->prebits--; + } + /* + * Check that CPU code defining pribits didn't violate + * architectural constraints our implementation relies on. + */ + g_assert(cs->pribits >= 4 && cs->pribits <= 8); + + /* + * gicv3_cpuif_reginfo[] defines ICC_AP*R0_EL1; add definitions + * for ICC_AP*R{1,2,3}_EL1 if the prebits value requires them. + */ + if (cs->prebits >= 6) { + define_arm_cp_regs(cpu, gicv3_cpuif_icc_apxr1_reginfo); + } + if (cs->prebits == 7) { + define_arm_cp_regs(cpu, gicv3_cpuif_icc_apxr23_reginfo); + } + if (arm_feature(&cpu->env, ARM_FEATURE_EL2)) { int j; |