+/* Physical Interrupt Target EL Lookup Table
+ *
+ * [ From ARM ARM section G1.13.4 (Table G1-15) ]
+ *
+ * The below multi-dimensional table is used for looking up the target
+ * exception level given numerous condition criteria. Specifically, the
+ * target EL is based on SCR and HCR routing controls as well as the
+ * currently executing EL and secure state.
+ *
+ * Dimensions:
+ * target_el_table[2][2][2][2][2][4]
+ * | | | | | +--- Current EL
+ * | | | | +------ Non-secure(0)/Secure(1)
+ * | | | +--------- HCR mask override
+ * | | +------------ SCR exec state control
+ * | +--------------- SCR mask override
+ * +------------------ 32-bit(0)/64-bit(1) EL3
+ *
+ * The table values are as such:
+ * 0-3 = EL0-EL3
+ * -1 = Cannot occur
+ *
+ * The ARM ARM target EL table includes entries indicating that an "exception
+ * is not taken". The two cases where this is applicable are:
+ * 1) An exception is taken from EL3 but the SCR does not have the exception
+ * routed to EL3.
+ * 2) An exception is taken from EL2 but the HCR does not have the exception
+ * routed to EL2.
+ * In these two cases, the below table contain a target of EL1. This value is
+ * returned as it is expected that the consumer of the table data will check
+ * for "target EL >= current EL" to ensure the exception is not taken.
+ *
+ * SCR HCR
+ * 64 EA AMO From
+ * BIT IRQ IMO Non-secure Secure
+ * EL3 FIQ RW FMO EL0 EL1 EL2 EL3 EL0 EL1 EL2 EL3
+ */
+const int8_t target_el_table[2][2][2][2][2][4] = {
+ {{{{/* 0 0 0 0 */{ 1, 1, 2, -1 },{ 3, -1, -1, 3 },},
+ {/* 0 0 0 1 */{ 2, 2, 2, -1 },{ 3, -1, -1, 3 },},},
+ {{/* 0 0 1 0 */{ 1, 1, 2, -1 },{ 3, -1, -1, 3 },},
+ {/* 0 0 1 1 */{ 2, 2, 2, -1 },{ 3, -1, -1, 3 },},},},
+ {{{/* 0 1 0 0 */{ 3, 3, 3, -1 },{ 3, -1, -1, 3 },},
+ {/* 0 1 0 1 */{ 3, 3, 3, -1 },{ 3, -1, -1, 3 },},},
+ {{/* 0 1 1 0 */{ 3, 3, 3, -1 },{ 3, -1, -1, 3 },},
+ {/* 0 1 1 1 */{ 3, 3, 3, -1 },{ 3, -1, -1, 3 },},},},},
+ {{{{/* 1 0 0 0 */{ 1, 1, 2, -1 },{ 1, 1, -1, 1 },},
+ {/* 1 0 0 1 */{ 2, 2, 2, -1 },{ 1, 1, -1, 1 },},},
+ {{/* 1 0 1 0 */{ 1, 1, 1, -1 },{ 1, 1, -1, 1 },},
+ {/* 1 0 1 1 */{ 2, 2, 2, -1 },{ 1, 1, -1, 1 },},},},
+ {{{/* 1 1 0 0 */{ 3, 3, 3, -1 },{ 3, 3, -1, 3 },},
+ {/* 1 1 0 1 */{ 3, 3, 3, -1 },{ 3, 3, -1, 3 },},},
+ {{/* 1 1 1 0 */{ 3, 3, 3, -1 },{ 3, 3, -1, 3 },},
+ {/* 1 1 1 1 */{ 3, 3, 3, -1 },{ 3, 3, -1, 3 },},},},},
+};
+
+/*
+ * Determine the target EL for physical exceptions
+ */
+static inline uint32_t arm_phys_excp_target_el(CPUState *cs, uint32_t excp_idx,
+ uint32_t cur_el, bool secure)
+{
+ CPUARMState *env = cs->env_ptr;
+ int rw = ((env->cp15.scr_el3 & SCR_RW) == SCR_RW);
+ int scr;
+ int hcr;
+ int target_el;
+ int is64 = arm_el_is_aa64(env, 3);
+
+ switch (excp_idx) {
+ case EXCP_IRQ:
+ scr = ((env->cp15.scr_el3 & SCR_IRQ) == SCR_IRQ);
+ hcr = ((env->cp15.hcr_el2 & HCR_IMO) == HCR_IMO);
+ break;
+ case EXCP_FIQ:
+ scr = ((env->cp15.scr_el3 & SCR_FIQ) == SCR_FIQ);
+ hcr = ((env->cp15.hcr_el2 & HCR_FMO) == HCR_FMO);
+ break;
+ default:
+ scr = ((env->cp15.scr_el3 & SCR_EA) == SCR_EA);
+ hcr = ((env->cp15.hcr_el2 & HCR_AMO) == HCR_AMO);
+ break;
+ };
+
+ /* If HCR.TGE is set then HCR is treated as being 1 */
+ hcr |= ((env->cp15.hcr_el2 & HCR_TGE) == HCR_TGE);
+
+ /* Perform a table-lookup for the target EL given the current state */
+ target_el = target_el_table[is64][scr][rw][hcr][secure][cur_el];
+
+ assert(target_el > 0);
+
+ return target_el;
+}
+
+/*
+ * Determine the target EL for a given exception type.
+ */
+unsigned int arm_excp_target_el(CPUState *cs, unsigned int excp_idx)
+{
+ ARMCPU *cpu = ARM_CPU(cs);
+ CPUARMState *env = &cpu->env;
+ unsigned int cur_el = arm_current_el(env);
+ unsigned int target_el;
+ bool secure = arm_is_secure(env);
+
+ switch (excp_idx) {
+ case EXCP_HVC:
+ case EXCP_HYP_TRAP:
+ target_el = 2;
+ break;
+ case EXCP_SMC:
+ target_el = 3;
+ break;
+ case EXCP_FIQ:
+ case EXCP_IRQ:
+ target_el = arm_phys_excp_target_el(cs, excp_idx, cur_el, secure);
+ break;
+ case EXCP_VIRQ:
+ case EXCP_VFIQ:
+ target_el = 1;
+ break;
+ default:
+ target_el = MAX(cur_el, 1);
+ break;
+ }
+ return target_el;
+}
+
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