From f10827a845bbbb0354617cc1a69e95e4c1eb18ce Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Cl=C3=A9ment=20Chigot?= Date: Mon, 15 Jul 2024 10:46:39 +0200 Subject: [PATCH] hw/ppc: fix decrementer with BookE timers MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The BookE decrementer stops at 0, meaning that it won't decremented towards "negative" values. However, the current logic is inverted: decr is updated solely when the resulting value would be negative. Signed-off-by: Clément Chigot Fixes: 8e0a5ac87800 ("hw/ppc: Avoid decrementer rounding errors") Reviewed-by: Cédric Le Goater Signed-off-by: Nicholas Piggin --- hw/ppc/ppc.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/hw/ppc/ppc.c b/hw/ppc/ppc.c index fde4619412..b86b5847de 100644 --- a/hw/ppc/ppc.c +++ b/hw/ppc/ppc.c @@ -728,7 +728,9 @@ static inline int64_t __cpu_ppc_load_decr(CPUPPCState *env, int64_t now, int64_t decr; n = ns_to_tb(tb_env->decr_freq, now); - if (next > n && tb_env->flags & PPC_TIMER_BOOKE) { + + /* BookE timers stop when reaching 0. */ + if (next < n && tb_env->flags & PPC_TIMER_BOOKE) { decr = 0; } else { decr = next - n;