From: notaz Date: Thu, 16 Oct 2014 01:15:17 +0000 (+0300) Subject: fix some races for recording X-Git-Url: https://notaz.gp2x.de/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=72ef318cfcacd741d1f8fff31b76c31f52a6b0f3;p=megadrive.git fix some races for recording --- diff --git a/main.c b/main.c index 0cae7e6..0a52e57 100644 --- a/main.c +++ b/main.c @@ -22,11 +22,16 @@ static struct { uint8_t fixed_state[4]; uint32_t fixed_state32; }; + union { + uint8_t pending_state[4]; + uint32_t pending_state32; + }; uint32_t stream_enable_to:1; uint32_t stream_enable_from:1; uint32_t stream_started:1; uint32_t stream_ended:1; uint32_t use_readinc:1; + uint32_t use_pending:1; uint32_t frame_cnt; uint32_t edge_cnt; uint32_t t_i; @@ -53,6 +58,7 @@ void yield(void) { } +/* portb handles TH */ static void portb_isr_fixed(void) { uint32_t isfr, th; @@ -128,6 +134,7 @@ static noinline void do_from_step(void) // should hopefully give atomic fixed_state read.. s = g.fixed_state32; + g.fixed_state32 = g.pending_state32; g.stream_from[g.f_i][0] = s; g.stream_from[g.f_i][1] = s >> 8; g.f_i = (g.f_i + 1) & STREAM_BUF_MASK; @@ -252,6 +259,7 @@ static void do_start_seq(void) } } else if (g.stream_enable_from) { + g.use_pending = 1; if (g.use_readinc) { attachInterruptVector(IRQ_PORTB, portb_isr_fixed_do_from); @@ -262,9 +270,6 @@ static void do_start_seq(void) attachInterruptVector(IRQ_PORTC, portc_isr_frameinc_do_from); } - - // prep first frame already - do_from_step(); } __enable_irq(); } @@ -274,9 +279,10 @@ static void clear_state(void) { g.stream_enable_to = 0; g.stream_enable_from = 0; - g.use_readinc = 0; g.stream_started = 0; g.stream_ended = 0; + g.use_readinc = 0; + g.use_pending = 0; g.t_i = g.t_o = 0; g.f_i = g.f_o = 0; g.frame_cnt = 0; @@ -302,7 +308,11 @@ static void do_usb(void *buf) switch (pkt->type) { case PKT_FIXED_STATE: - memcpy(g.fixed_state, pkt->data, sizeof(g.fixed_state)); + memcpy(&i, pkt->data, sizeof(i)); + if (g.use_pending) + g.pending_state32 = i; + else + g.fixed_state32 = i; break; case PKT_STREAM_ENABLE: __disable_irq();