From b345b48078d79ebe154a50f75e66999605abcc70 Mon Sep 17 00:00:00 2001 From: Alistair Francis Date: Tue, 30 Jul 2019 16:35:24 -0700 Subject: [PATCH] target/riscv: Create function to test if FP is enabled MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Let's create a function that tests if floating point support is enabled. We can then protect all floating point operations based on if they are enabled. This patch so far doesn't change anything, it's just preparing for the Hypervisor support for floating point operations. Signed-off-by: Alistair Francis Reviewed-by: Philippe Mathieu-Daudé Reviewed-by: Christophe de Dinechin Signed-off-by: Palmer Dabbelt --- target/riscv/cpu.h | 6 +++++- target/riscv/cpu_helper.c | 10 ++++++++++ target/riscv/csr.c | 20 +++++++++++--------- 3 files changed, 26 insertions(+), 10 deletions(-) diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h index 18d91d0920..16efe8c860 100644 --- a/target/riscv/cpu.h +++ b/target/riscv/cpu.h @@ -255,6 +255,7 @@ void riscv_cpu_do_interrupt(CPUState *cpu); int riscv_cpu_gdb_read_register(CPUState *cpu, uint8_t *buf, int reg); int riscv_cpu_gdb_write_register(CPUState *cpu, uint8_t *buf, int reg); bool riscv_cpu_exec_interrupt(CPUState *cs, int interrupt_request); +bool riscv_cpu_fp_enabled(CPURISCVState *env); int riscv_cpu_mmu_index(CPURISCVState *env, bool ifetch); hwaddr riscv_cpu_get_phys_page_debug(CPUState *cpu, vaddr addr); void riscv_cpu_do_unaligned_access(CPUState *cs, vaddr addr, @@ -298,7 +299,10 @@ static inline void cpu_get_tb_cpu_state(CPURISCVState *env, target_ulong *pc, #ifdef CONFIG_USER_ONLY *flags = TB_FLAGS_MSTATUS_FS; #else - *flags = cpu_mmu_index(env, 0) | (env->mstatus & MSTATUS_FS); + *flags = cpu_mmu_index(env, 0); + if (riscv_cpu_fp_enabled(env)) { + *flags |= env->mstatus & MSTATUS_FS; + } #endif } diff --git a/target/riscv/cpu_helper.c b/target/riscv/cpu_helper.c index e32b6126af..96373b67d8 100644 --- a/target/riscv/cpu_helper.c +++ b/target/riscv/cpu_helper.c @@ -71,6 +71,16 @@ bool riscv_cpu_exec_interrupt(CPUState *cs, int interrupt_request) #if !defined(CONFIG_USER_ONLY) +/* Return true is floating point support is currently enabled */ +bool riscv_cpu_fp_enabled(CPURISCVState *env) +{ + if (env->mstatus & MSTATUS_FS) { + return true; + } + + return false; +} + int riscv_cpu_claim_interrupts(RISCVCPU *cpu, uint32_t interrupts) { CPURISCVState *env = &cpu->env; diff --git a/target/riscv/csr.c b/target/riscv/csr.c index e0d4586760..2789215b5e 100644 --- a/target/riscv/csr.c +++ b/target/riscv/csr.c @@ -46,7 +46,7 @@ void riscv_set_csr_ops(int csrno, riscv_csr_operations *ops) static int fs(CPURISCVState *env, int csrno) { #if !defined(CONFIG_USER_ONLY) - if (!env->debugger && !(env->mstatus & MSTATUS_FS)) { + if (!env->debugger && !riscv_cpu_fp_enabled(env)) { return -1; } #endif @@ -108,7 +108,7 @@ static int pmp(CPURISCVState *env, int csrno) static int read_fflags(CPURISCVState *env, int csrno, target_ulong *val) { #if !defined(CONFIG_USER_ONLY) - if (!env->debugger && !(env->mstatus & MSTATUS_FS)) { + if (!env->debugger && !riscv_cpu_fp_enabled(env)) { return -1; } #endif @@ -119,7 +119,7 @@ static int read_fflags(CPURISCVState *env, int csrno, target_ulong *val) static int write_fflags(CPURISCVState *env, int csrno, target_ulong val) { #if !defined(CONFIG_USER_ONLY) - if (!env->debugger && !(env->mstatus & MSTATUS_FS)) { + if (!env->debugger && !riscv_cpu_fp_enabled(env)) { return -1; } env->mstatus |= MSTATUS_FS; @@ -131,7 +131,7 @@ static int write_fflags(CPURISCVState *env, int csrno, target_ulong val) static int read_frm(CPURISCVState *env, int csrno, target_ulong *val) { #if !defined(CONFIG_USER_ONLY) - if (!env->debugger && !(env->mstatus & MSTATUS_FS)) { + if (!env->debugger && !riscv_cpu_fp_enabled(env)) { return -1; } #endif @@ -142,7 +142,7 @@ static int read_frm(CPURISCVState *env, int csrno, target_ulong *val) static int write_frm(CPURISCVState *env, int csrno, target_ulong val) { #if !defined(CONFIG_USER_ONLY) - if (!env->debugger && !(env->mstatus & MSTATUS_FS)) { + if (!env->debugger && !riscv_cpu_fp_enabled(env)) { return -1; } env->mstatus |= MSTATUS_FS; @@ -154,7 +154,7 @@ static int write_frm(CPURISCVState *env, int csrno, target_ulong val) static int read_fcsr(CPURISCVState *env, int csrno, target_ulong *val) { #if !defined(CONFIG_USER_ONLY) - if (!env->debugger && !(env->mstatus & MSTATUS_FS)) { + if (!env->debugger && !riscv_cpu_fp_enabled(env)) { return -1; } #endif @@ -166,7 +166,7 @@ static int read_fcsr(CPURISCVState *env, int csrno, target_ulong *val) static int write_fcsr(CPURISCVState *env, int csrno, target_ulong val) { #if !defined(CONFIG_USER_ONLY) - if (!env->debugger && !(env->mstatus & MSTATUS_FS)) { + if (!env->debugger && !riscv_cpu_fp_enabled(env)) { return -1; } env->mstatus |= MSTATUS_FS; @@ -307,6 +307,7 @@ static int write_mstatus(CPURISCVState *env, int csrno, target_ulong val) { target_ulong mstatus = env->mstatus; target_ulong mask = 0; + int dirty; /* flush tlb on mstatus fields that affect VM */ if (env->priv_ver <= PRIV_VERSION_1_09_1) { @@ -340,8 +341,9 @@ static int write_mstatus(CPURISCVState *env, int csrno, target_ulong val) mstatus = (mstatus & ~mask) | (val & mask); - int dirty = ((mstatus & MSTATUS_FS) == MSTATUS_FS) | - ((mstatus & MSTATUS_XS) == MSTATUS_XS); + dirty = (riscv_cpu_fp_enabled(env) && + ((mstatus & MSTATUS_FS) == MSTATUS_FS)) | + ((mstatus & MSTATUS_XS) == MSTATUS_XS); mstatus = set_field(mstatus, MSTATUS_SD, dirty); env->mstatus = mstatus;