From bd3a0826e0e3c2b9d910f926e2a2fdcbd582a277 Mon Sep 17 00:00:00 2001 From: kub Date: Tue, 4 Feb 2025 21:55:07 +0100 Subject: [PATCH] 32x, minor timer optimization --- pico/32x/sh2soc.c | 16 +++++++--------- 1 file changed, 7 insertions(+), 9 deletions(-) diff --git a/pico/32x/sh2soc.c b/pico/32x/sh2soc.c index 0eebe427..7d1e0d45 100644 --- a/pico/32x/sh2soc.c +++ b/pico/32x/sh2soc.c @@ -190,7 +190,7 @@ static void dmac_trigger(SH2 *sh2, struct dma_chan *chan) } // timer state - FIXME -static u32 timer_cycles[2]; +static u32 timer_cycles[2]; // TODO save this in state! static u32 timer_tick_cycles[2]; static u32 timer_tick_factor[2]; @@ -207,13 +207,12 @@ void p32x_timers_recalc(void) sh2s[i].state |= SH2_TIMER_RUN; tmp = PREG8(sh2s[i].peri_regs, 0x80) & 7; // Sclk cycles per timer tick - cycles = 2; - if (tmp) - cycles <<= tmp + 4; - if (tmp >= 6) - cycles <<= 1; + if (tmp >= 6) tmp++; + if (tmp) tmp += 5; + else tmp = 1; + cycles = 1 << tmp; timer_tick_cycles[i] = cycles; - timer_tick_factor[i] = (1ULL << 32) / cycles; + timer_tick_factor[i] = tmp; timer_cycles[i] = 0; elprintf(EL_32XP, "WDT cycles[%d] = %d", i, cycles); } @@ -228,8 +227,7 @@ NOINLINE void p32x_timer_do(SH2 *sh2, unsigned int m68k_slice) // WDT timer timer_cycles[i] += cycles; if (timer_cycles[i] > timer_tick_cycles[i]) { - // cnt = timer_cycles[i] / timer_tick_cycles[i]; - cnt = (1ULL * timer_cycles[i] * timer_tick_factor[i]) >> 32; + cnt = (timer_cycles[i] >> timer_tick_factor[i]); timer_cycles[i] -= timer_tick_cycles[i] * cnt; cnt += PREG8(pregs, 0x81); -- 2.39.5