> -----Original Message-----
> From: Brian Cain <brian.c...@oss.qualcomm.com>
> Sent: Friday, February 28, 2025 11:29 PM
> To: qemu-devel@nongnu.org
> Cc: brian.c...@oss.qualcomm.com; richard.hender...@linaro.org;
> phi...@linaro.org; quic_mathb...@quicinc.com; a...@rev.ng; a...@rev.ng;
> quic_mlie...@quicinc.com; ltaylorsimp...@gmail.com;
> alex.ben...@linaro.org; quic_mbur...@quicinc.com;
> sidn...@quicinc.com; Brian Cain <bc...@quicinc.com>
> Subject: [PATCH 34/39] target/hexagon: Add TLB, k0 {un,}lock
>
> From: Brian Cain <bc...@quicinc.com>
>
> Signed-off-by: Brian Cain <brian.c...@oss.qualcomm.com>
> ---
> target/hexagon/sys_macros.h | 8 +--
> target/hexagon/op_helper.c | 104
> ++++++++++++++++++++++++++++++++++++
> 2 files changed, 108 insertions(+), 4 deletions(-)
>
> diff --git a/target/hexagon/sys_macros.h b/target/hexagon/sys_macros.h
> index 3c4c3c7aa5..e5dc1ce0ab 100644
> --- a/target/hexagon/sys_macros.h
> +++ b/target/hexagon/sys_macros.h
> @@ -143,11 +143,11 @@
> #define fDCINVIDX(REG)
> #define fDCINVA(REG) do { REG = REG; } while (0) /* Nothing to do in qemu
> */
>
> -#define fSET_TLB_LOCK() g_assert_not_reached()
> -#define fCLEAR_TLB_LOCK() g_assert_not_reached()
> +#define fSET_TLB_LOCK() hex_tlb_lock(env);
> +#define fCLEAR_TLB_LOCK() hex_tlb_unlock(env);
Move these to the patch that implements TLB lock/unlock.
>
> -#define fSET_K0_LOCK() g_assert_not_reached()
> -#define fCLEAR_K0_LOCK() g_assert_not_reached()
> +#define fSET_K0_LOCK() hex_k0_lock(env);
> +#define fCLEAR_K0_LOCK() hex_k0_unlock(env);
>
> #define fTLB_IDXMASK(INDEX) \
> ((INDEX) & (fPOW2_ROUNDUP(fCAST4u(env_archcpu(env)->num_tlbs)) -
> 1)) diff --git a/target/hexagon/op_helper.c b/target/hexagon/op_helper.c
> index 702c3dd3c6..f3b14fbf58 100644
> --- a/target/hexagon/op_helper.c
> +++ b/target/hexagon/op_helper.c
> @@ -1184,6 +1184,110 @@ void HELPER(modify_ssr)(CPUHexagonState
> *env, uint32_t new, uint32_t old)
> BQL_LOCK_GUARD();
> hexagon_modify_ssr(env, new, old);
> }
> +
> +static void hex_k0_lock(CPUHexagonState *env) {
> + BQL_LOCK_GUARD();
> + g_assert((env->k0_lock_count == 0) || (env->k0_lock_count == 1));
> +
> + uint32_t syscfg = arch_get_system_reg(env, HEX_SREG_SYSCFG);
> + if (GET_SYSCFG_FIELD(SYSCFG_K0LOCK, syscfg)) {
> + if (env->k0_lock_state == HEX_LOCK_QUEUED) {
> + env->next_PC += 4;
> + env->k0_lock_count++;
> + env->k0_lock_state = HEX_LOCK_OWNER;
> + SET_SYSCFG_FIELD(env, SYSCFG_K0LOCK, 1);
> + return;
> + }
> + if (env->k0_lock_state == HEX_LOCK_OWNER) {
> + qemu_log_mask(LOG_GUEST_ERROR,
> + "Double k0lock at PC: 0x%x, thread may hang\n",
> + env->next_PC);
> + env->next_PC += 4;
> + CPUState *cs = env_cpu(env);
QEMU coding standards prefer to put declarations at the beginning of the code
block (just after the open curly brace).
> + cpu_interrupt(cs, CPU_INTERRUPT_HALT);
> + return;
> + }
> + env->k0_lock_state = HEX_LOCK_WAITING;
> + CPUState *cs = env_cpu(env);
Ditto
> + cpu_interrupt(cs, CPU_INTERRUPT_HALT);
> + } else {
> + env->next_PC += 4;
> + env->k0_lock_count++;
> + env->k0_lock_state = HEX_LOCK_OWNER;
> + SET_SYSCFG_FIELD(env, SYSCFG_K0LOCK, 1);
> + }
> +
> +}
> +
> +static void hex_k0_unlock(CPUHexagonState *env) {
> + BQL_LOCK_GUARD();
> + g_assert((env->k0_lock_count == 0) || (env->k0_lock_count == 1));
> +
> + /* Nothing to do if the k0 isn't locked by this thread */
> + uint32_t syscfg = arch_get_system_reg(env, HEX_SREG_SYSCFG);
> + if ((GET_SYSCFG_FIELD(SYSCFG_K0LOCK, syscfg) == 0) ||
> + (env->k0_lock_state != HEX_LOCK_OWNER)) {
> + qemu_log_mask(LOG_GUEST_ERROR,
> + "thread %d attempted to unlock k0 without having the "
> + "lock, k0_lock state = %d, syscfg:k0 = %d\n",
> + env->threadId, env->k0_lock_state,
> + GET_SYSCFG_FIELD(SYSCFG_K0LOCK, syscfg));
> + g_assert(env->k0_lock_state != HEX_LOCK_WAITING);
> + return;
> + }
> +
> + env->k0_lock_count--;
> + env->k0_lock_state = HEX_LOCK_UNLOCKED;
> + SET_SYSCFG_FIELD(env, SYSCFG_K0LOCK, 0);
> +
> + /* Look for a thread to unlock */
> + unsigned int this_threadId = env->threadId;
> + CPUHexagonState *unlock_thread = NULL;
> + CPUState *cs;
Ditto
Otherwise
Reviewed-by: Taylor Simpson <ltaylorsimp...@gmail.com>
