From 2cae1dae1c2c56eb5fe903df67472483edb26ded Mon Sep 17 00:00:00 2001 From: Jens Arnold Date: Tue, 4 May 2004 06:29:41 +0000 Subject: Unified & assembler optimized recording transfer routines: Smaller & 50% faster git-svn-id: svn://svn.rockbox.org/rockbox/trunk@4576 a1c6a512-1295-4272-9138-f99709370657 --- firmware/mpeg.c | 177 +++++++++++++++++++++++++++----------------------------- 1 file changed, 86 insertions(+), 91 deletions(-) (limited to 'firmware/mpeg.c') diff --git a/firmware/mpeg.c b/firmware/mpeg.c index 814217f26b..bf0512dfc2 100644 --- a/firmware/mpeg.c +++ b/firmware/mpeg.c @@ -460,47 +460,40 @@ static int get_unsaved_space(void) static long timing_info_index = 0; static long timing_info[1024]; #endif /* #ifdef DEBUG */ -static bool inverted_pr; static unsigned long num_rec_bytes; static unsigned long num_recorded_frames; static void drain_dma_buffer(void) { - if(inverted_pr) - { - while((*((volatile unsigned char *)PBDR_ADDR) & 0x40)) - { - or_b(0x08, &PADRH); - - while(*((volatile unsigned char *)PBDR_ADDR) & 0x80); - - /* It must take at least 5 cycles before - the data is read */ - asm(" nop\n nop\n nop\n"); - asm(" nop\n nop\n nop\n"); - and_b(~0x08, &PADRH); - - while(!(*((volatile unsigned char *)PBDR_ADDR) & 0x80)); - } - } - else - { - while((*((volatile unsigned char *)PBDR_ADDR) & 0x40)) - { - and_b(~0x08, &PADRH); - - while(*((volatile unsigned char *)PBDR_ADDR) & 0x80); + asm ( + "mov #0x40,r2 \n" /* mask for EOD check */ + "bra .d_start \n" + "mov.b @%0,r1 \n" /* read PBDR (first time) */ + + ".d_loop: \n" + "xor.b #0x08,@(r0,gbr) \n" /* set PR active */ + ".d_wait1: \n" + "mov.b @%0,r1 \n" /* read PBDR */ + "cmp/pz r1 \n" /* and wait for PRTW */ + "bf .d_wait1 \n" + + "xor.b #0x08,@(r0,gbr) \n" /* reset PR to inactive */ + ".d_wait2: \n" + "mov.b @%0,r1 \n" /* read PBDR */ + "cmp/pz r1 \n" /* and wait for /PRTW */ + "bt .d_wait2 \n" - /* It must take at least 5 cycles before - the data is read */ - asm(" nop\n nop\n nop\n"); - asm(" nop\n nop\n nop\n"); - - or_b(0x08, &PADRH); - - while(!(*((volatile unsigned char *)PBDR_ADDR) & 0x80)); - } - } + ".d_start: \n" + "tst r1,r2 \n" /* EOD low? */ + "bf .d_loop \n" /* no: next pass */ + + : /* outputs */ + : /* inputs */ + /* %0 */ "r"(PBDR_ADDR), + /* %1 = r0 */ "z"(&PADRH) + : /* clobbers */ + "r1","r2" + ); } #endif /* #ifdef HAVE_MAS3587F */ @@ -517,59 +510,61 @@ void rec_tick(void) timing_info[timing_info_index++] = current_tick; TCNT2 = 0; #endif /* #ifdef DEBUG */ - /* We read as long as EOD is high, but max 30 bytes. - This code is optimized, and should probably be - written in assembler instead. */ - if(inverted_pr) - { - i = 0; - while((*((volatile unsigned char *)PBDR_ADDR) & 0x40) - && i < 30) - { - or_b(0x08, &PADRH); - - while(*((volatile unsigned char *)PBDR_ADDR) & 0x80); - - /* It must take at least 5 cycles before - the data is read */ - asm(" nop\n nop\n nop\n"); - mp3buf[mp3buf_write++] = *(unsigned char *)0x4000000; - - if(mp3buf_write >= mp3buflen) - mp3buf_write = 0; - - i++; - - and_b(~0x08, &PADRH); - - /* No wait for /RTW, cause it's not necessary */ - } - } - else /* !inverted_pr */ - { - i = 0; - while((*((volatile unsigned char *)PBDR_ADDR) & 0x40) - && i < 30) - { - and_b(~0x08, &PADRH); - - while(*((volatile unsigned char *)PBDR_ADDR) & 0x80); - - /* It must take at least 5 cycles before - the data is read */ - asm(" nop\n nop\n nop\n"); - mp3buf[mp3buf_write++] = *(unsigned char *)0x4000000; - - if(mp3buf_write >= mp3buflen) - mp3buf_write = 0; - - i++; - - or_b(0x08, &PADRH); - - /* No wait for /RTW, cause it's not necessary */ - } - } + /* We read as long as EOD is high, but max 30 bytes. */ + asm ( + "mov #30,r3 \n" /* i_max = 30 */ + "mov #0x40,r2 \n" /* mask for EOD check */ + "mov #0,%0 \n" /* i = 0; */ + "add %2,%1 \n" /* mp3buf_write -> cur_addr */ + "add %2,%3 \n" /* mp3buflen -> end_addr */ + "bra .r_start \n" + "mov.b @%4,r1 \n" /* read PBDR (first time) */ + + ".align 2 \n" + + ".r_loop: \n" + "xor.b #0x08,@(r0,gbr) \n" /* set PR active */ + ".r_wait1: \n" + "mov.b @%4,r1 \n" /* read PBDR */ + "cmp/pz r1 \n" /* and wait for PRTW */ + "bf .r_wait1 \n" + + "mov.b @%6,r1 \n" /* read byte from mas */ + "add #1,%0 \n" /* i++; */ + "mov.b r1,@%1 \n" /* store byte */ + "add #1,%1 \n" /* increment current address */ + + "cmp/hi %1,%3 \n" /* end address reached? */ + "bt .r_nowrap \n" /* no: do nothing */ + "mov %2,%1 \n" /* yes: reset to start address */ + ".r_nowrap: \n" + + "xor.b #0x08,@(r0,gbr) \n" /* set PR inactive again */ + ".r_wait2: \n" + "mov.b @%4,r1 \n" /* read PBDR */ + "cmp/pz r1 \n" /* and wait for /PRTW */ + "bt .r_wait2 \n" + + ".r_start: \n" + "tst r2,r1 \n" /* EOD low? */ + "bt .r_end \n" /* yes: end of transfer */ + "cmp/hi %0,r3 \n" /* i < i_max? */ + "bt .r_loop \n" /* yes: next pass */ + + ".r_end: \n" + "sub %2,%1 \n" /* cur_addr -> mp3buf_write */ + : /* outputs */ + /* %0 */ "=&r"(i), + /* %1, in & out */ "+r"(mp3buf_write) + : /* inputs */ + /* %2 */ "r"(mp3buf), + /* %3 */ "r"(mp3buflen), + /* %4 */ "r"(PBDR_ADDR), + /* %5 = r0 */ "z"(&PADRH), + /* %6 */ "r"(0x4000000) + : /* clobbers */ + "r1","r2","r3" + ); #ifdef DEBUG timing_info[timing_info_index++] = TCNT2 + (i << 16); timing_info_index &= 0x3ff; @@ -2631,11 +2626,11 @@ void mpeg_init(void) #ifdef HAVE_MAS3587F if(read_hw_mask() & PR_ACTIVE_HIGH) - inverted_pr = true; + and_b(~0x08, &PADRH); else - inverted_pr = false; + or_b(0x08, &PADRH); #endif /* #ifdef HAVE_MAS3587F */ - + #ifdef DEBUG dbg_timer_start(); dbg_cnt2us(0); -- cgit v1.2.3