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author | Philippe Mathieu-Daudé <f4bug@amsat.org> | 2020-10-12 11:57:48 +0200 |
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committer | Philippe Mathieu-Daudé <f4bug@amsat.org> | 2020-10-17 11:13:15 +0200 |
commit | 2dc29222a6f7c87300c1a7e1982e11422d34595e (patch) | |
tree | 2c1faf1dc625d2d038a828b5b081fd3e9838f68f /target/mips | |
parent | 88a844545e0fb1fa95a55888fb31024fcfc9720b (diff) | |
download | qemu-2dc29222a6f7c87300c1a7e1982e11422d34595e.zip qemu-2dc29222a6f7c87300c1a7e1982e11422d34595e.tar.gz qemu-2dc29222a6f7c87300c1a7e1982e11422d34595e.tar.bz2 |
target/mips: Move cpu_mips_get_random() with CP0 helpers
The get_random() helper uses the CP0_Wired register, which is
unrelated to the CP0_Count register used as timer.
Commit e16fe40c872 ("Move the MIPS CPU timer in a separate file")
incorrectly moved this get_random() helper with timer specific
code. Move it back to generic CP0 helpers.
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Aleksandar Markovic <aleksandar.qemu.devel@gmail.com>
Reviewed-by: Luc Michel <luc@lmichel.fr>
Message-Id: <20201012095804.3335117-6-f4bug@amsat.org>
Diffstat (limited to 'target/mips')
-rw-r--r-- | target/mips/cp0_helper.c | 25 | ||||
-rw-r--r-- | target/mips/cp0_timer.c | 25 | ||||
-rw-r--r-- | target/mips/internal.h | 2 |
3 files changed, 26 insertions, 26 deletions
diff --git a/target/mips/cp0_helper.c b/target/mips/cp0_helper.c index de64add..12143ac 100644 --- a/target/mips/cp0_helper.c +++ b/target/mips/cp0_helper.c @@ -203,6 +203,31 @@ static void sync_c0_entryhi(CPUMIPSState *cpu, int tc) *tcst |= asid; } +/* XXX: do not use a global */ +uint32_t cpu_mips_get_random(CPUMIPSState *env) +{ + static uint32_t seed = 1; + static uint32_t prev_idx; + uint32_t idx; + uint32_t nb_rand_tlb = env->tlb->nb_tlb - env->CP0_Wired; + + if (nb_rand_tlb == 1) { + return env->tlb->nb_tlb - 1; + } + + /* Don't return same value twice, so get another value */ + do { + /* + * Use a simple algorithm of Linear Congruential Generator + * from ISO/IEC 9899 standard. + */ + seed = 1103515245 * seed + 12345; + idx = (seed >> 16) % nb_rand_tlb + env->CP0_Wired; + } while (idx == prev_idx); + prev_idx = idx; + return idx; +} + /* CP0 helpers */ target_ulong helper_mfc0_mvpcontrol(CPUMIPSState *env) { diff --git a/target/mips/cp0_timer.c b/target/mips/cp0_timer.c index bd7efb1..9c38e9d 100644 --- a/target/mips/cp0_timer.c +++ b/target/mips/cp0_timer.c @@ -29,31 +29,6 @@ #define TIMER_PERIOD 10 /* 10 ns period for 100 Mhz frequency */ -/* XXX: do not use a global */ -uint32_t cpu_mips_get_random(CPUMIPSState *env) -{ - static uint32_t seed = 1; - static uint32_t prev_idx = 0; - uint32_t idx; - uint32_t nb_rand_tlb = env->tlb->nb_tlb - env->CP0_Wired; - - if (nb_rand_tlb == 1) { - return env->tlb->nb_tlb - 1; - } - - /* Don't return same value twice, so get another value */ - do { - /* - * Use a simple algorithm of Linear Congruential Generator - * from ISO/IEC 9899 standard. - */ - seed = 1103515245 * seed + 12345; - idx = (seed >> 16) % nb_rand_tlb + env->CP0_Wired; - } while (idx == prev_idx); - prev_idx = idx; - return idx; -} - /* MIPS R4K timer */ static void cpu_mips_timer_update(CPUMIPSState *env) { diff --git a/target/mips/internal.h b/target/mips/internal.h index b811f54..dd8a780 100644 --- a/target/mips/internal.h +++ b/target/mips/internal.h @@ -144,6 +144,7 @@ void r4k_helper_tlbr(CPUMIPSState *env); void r4k_helper_tlbinv(CPUMIPSState *env); void r4k_helper_tlbinvf(CPUMIPSState *env); void r4k_invalidate_tlb(CPUMIPSState *env, int idx, int use_extra); +uint32_t cpu_mips_get_random(CPUMIPSState *env); void mips_cpu_do_transaction_failed(CPUState *cs, hwaddr physaddr, vaddr addr, unsigned size, @@ -209,7 +210,6 @@ void cpu_state_reset(CPUMIPSState *s); void cpu_mips_realize_env(CPUMIPSState *env); /* cp0_timer.c */ -uint32_t cpu_mips_get_random(CPUMIPSState *env); uint32_t cpu_mips_get_count(CPUMIPSState *env); void cpu_mips_store_count(CPUMIPSState *env, uint32_t value); void cpu_mips_store_compare(CPUMIPSState *env, uint32_t value); |