/*************************************************************************** * __________ __ ___. * Open \______ \ ____ ____ | | _\_ |__ _______ ___ * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ / * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < < * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \ * \/ \/ \/ \/ \/ * $Id$ * * Copyright (C) 2006 Thom Johansen * Portions Copyright (C) 2007 Michael Sevakis * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version 2 * of the License, or (at your option) any later version. * * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY * KIND, either express or implied. * ****************************************************************************/ #include "config.h" /**************************************************************************** * void pga_process(struct dsp_proc_entry *this, struct dsp_buffer **buf_p) */ .section .text .align 2 .global pga_process pga_process: | input: 4(sp) = this, 8(sp) = buf_p movem.l 4(%sp), %a0-%a1 | %a0 = this, %a1 = buf_p move.l (%a0), %a0 | %a0 = this->data = &pga_data move.l (%a0), %a0 | %a0 = data->gain move.l (%a1), %a1 | %a1 = buf = *buf_p lea.l -20(%sp), %sp | save registers movem.l %d2-%d4/%a2-%a3, (%sp) | clr.l %d1 | %d1 = buf->format.num_channels move.b 17(%a1), %d1 | 10: | channel loop | move.l (%a1), %d0 | %d0 = buf->remcount move.l (%a1, %d1.l*4), %a2 | %a2 = s = buf->p32[ch-1] move.l %a2, %a3 | %a3 = d = s move.l (%a2)+, %d2 | %d2 = *s++, mac.l %a0, %d2, (%a2)+, %d2, %acc0 | %acc0 = S(n)*gain, load S(n+1) subq.l #1, %d0 | --count > 0 ? : effectively n++ ble.b 30f | loop done | no? finish up 20: | loop | move.l %accext01, %d4 | fetch S(n-1)[7:0] movclr.l %acc0, %d3 | fetch S(n-1)[40:8] in %d5[31:0] asl.l #8, %d3 | *s++ = (S(n-1)[40:8] << 8) | S(n-1)[7:0] mac.l %a0, %d2, (%a2)+, %d2, %acc0 | %acc0 = S(n)*gain, load S(n+1) move.b %d4, %d3 | move.l %d3, (%a3)+ | subq.l #1, %d0 | --count > 0 ? : effectively n++ bgt.b 20b | loop | yes? do more samples 30: | loop done | move.l %accext01, %d4 | fetch S(n-1)[7:0] movclr.l %acc0, %d3 | fetch S(n-1)[40:8] in %d5[31:0] asl.l #8, %d3 | *s = (S(n-1)[40:8] << 8) | S(n-1)[7:0] move.b %d4, %d3 | move.l %d3, (%a3) | subq.l #1, %d1 | next channel bgt.b 10b | channel loop | movem.l (%sp), %d2-%d4/%a2-%a3 | restore registers lea.l 20(%sp), %sp | cleanup stack rts | .size pga_process, .-pga_process /**************************************************************************** * void crossfeed_process(struct dsp_proc_entry *this, * struct dsp_buffer **buf_p) */ .section .text .align 2 .global crossfeed_process crossfeed_process: | input: 4(sp) = this, 8(sp) = buf_p lea.l -44(%sp), %sp | movem.l %d2-%d7/%a2-%a6, (%sp) | save all regs movem.l 48(%sp), %a1/%a4 | %a1 = this, %a4 = buf_p move.l (%a4), %a4 | %a4 = buf = *buf_p movem.l (%a4), %d7/%a4-%a5 | %d7 = buf->remcount, %a4 = buf->p32[0], | %a5 = buf->p32[1] move.l (%a1), %a1 | %a1 = &crossfeed_state move.l (%a1)+, %d6 | %d6 = direct gain movem.l 12(%a1), %d0-%d3 | fetch filter history samples lea.l 132(%a1), %a6 | %a6 = delay line wrap limit move.l (%a6), %a0 | fetch delay line address movem.l (%a1), %a1-%a3 | load filter coefs bra.b 20f | loop start | go to loop start point /* Register usage in loop: * %a0 = delay_p, %a1..%a3 = b0, b1, a1 (filter coefs), * %a4 = buf[0], %a5 = buf[1], * %a6 = delay line pointer wrap limit, * %d0..%d3 = history * %d4..%d5 = temp. * %d6 = direct gain, * %d7 = count */ 10: | loop | movclr.l %acc0, %d4 | write outputs move.l %d4, (%a4)+ | . movclr.l %acc1, %d5 | . move.l %d5, (%a5)+ | . 20: | loop start | mac.l %a2, %d0, (%a0)+, %d0, %acc0 | %acc0 = b1*dl[n - 1], %d0 = dl[n] mac.l %a1, %d0 , %acc0 | %acc0 += b0*dl[n] mac.l %a3, %d1, (%a5), %d5, %acc0 | %acc0 += a1*y_r[n - 1], load R mac.l %a2, %d2, (%a0)+, %d2, %acc1 | %acc1 = b1*dr[n - 1], %d2 = dr[n] mac.l %a1, %d2 , %acc1 | %acc1 += b0*dr[n] mac.l %a3, %d3, (%a4), %d4, %acc1 | %acc1 += a1*y_l[n - 1], load L movem.l %d4-%d5, -8(%a0) | save left & right inputs to delay line move.l %acc0, %d3 | get filtered delayed left sample (y_l[n]) move.l %acc1, %d1 | get filtered delayed right sample (y_r[n]) mac.l %d6, %d4, %acc0 | %acc0 += gain*x_l[n] mac.l %d6, %d5, %acc1 | %acc1 += gain*x_r[n] cmp.l %a6, %a0 | wrap %a0 if passed end bhs.b 30f | wrap buffer | tpf.l | trap the buffer wrap 30: | wrap buffer | ...fwd taken branches more costly lea.l -104(%a6), %a0 | wrap it up subq.l #1, %d7 | --count > 0 ? bgt.b 10b | loop | yes? do more movclr.l %acc0, %d4 | write last outputs move.l %d4, (%a4) | . movclr.l %acc1, %d5 | . move.l %d5, (%a5) | . movem.l %d0-%d3, -120(%a6) | ...history move.l %a0, (%a6) | ...delay_p movem.l (%sp), %d2-%d7/%a2-%a6 | restore all regs lea.l 44(%sp), %sp | rts | .size crossfeed_process,.-crossfeed_process /**************************************************************************** * int lin_resample_resample(struct resample_data *data, * struct dsp_buffer *src, * struct dsp_buffer *dst) */ .section .text .align 2 .global lin_resample_resample lin_resample_resample: | input: 4(sp) = data, 8(sp) = src, 12(sp) = dst lea.l -44(%sp), %sp | save non-volatiles movem.l %d2-%d7/%a2-%a6, (%sp) | movem.l 48(%sp), %a0-%a2 | %a0 = data | %a1 = src | %a2 = dst clr.l %d1 | %d1 = ch = src->format.num_channels move.b 17(%a1), %d1 | moveq.l #16, %d7 | %d7 = shift .lrs_channel_loop: | movem.l (%a0), %d2-%d3 | %d2 = delta = data->delta, | %d3 = phase = data->phase move.l (%a1), %d4 | %d4 = srcrem = src->remcount move.l 12(%a2), %d5 | %d5 = dstrem = dst->bufcount cmp.l #0x8000, %d4 | %d4 = MIN(srcrem, 0x8000) ble.b 10f | move.l #0x8000, %d4 | 10: | move.l (%a1, %d1.l*4), %a3 | %a3 = s = src->p32[ch] move.l (%a2, %d1.l*4), %a4 | %a4 = d = dst->p32[ch] move.l %d3, %d0 | %d0 = pos lsr.l %d7, %d0 | ... beq.b 11f | pos == 0? cmp.l %d4, %d0 | pos = MIN(pos, srcrem) blt.b 12f | move.l %d4, %d0 | pos = srcrem move.l -4(%a3, %d0.l*4), %d6 | %d6 = last = s[pos - 1] bra.w .lrs_channel_complete | at limit; nothing to do but next 11: | move.l 4(%a0, %d1.l*4), %d6 | %d6 = last = last_sample[ch] tpf.l | trap next move.l (last = s[pos - 1]) 12: | move.l -4(%a3, %d0.l*4), %d6 | %d6 = last = s[pos - 1] cmp.l #0x10000, %d2 | delta >= 1.0? bhs.b .lrs_downsample | yes? downsampling | /** Upsampling **/ | lea.l (%a3, %d0.l*4), %a3 | %a3 = &s[pos] sub.l %d4, %d0 | %d0 = pos - srcrem = -dte lsl.l %d7, %d2 | move delta to bits 30..15 lsr.l #1, %d2 | lsl.l %d7, %d3 | move phase to bits 30..15 lsr.l #1, %d3 | move.l (%a3)+, %a5 | %a5 = s[pos] move.l %a5, %a6 | %a6 = diff = s[pos] - last sub.l %d6, %a6 | bra.b 22f | /* Funky loop structure is to avoid emac latency stalls */ 20: | move.l (%a3)+, %a5 | %a5 = s[pos] move.l %a5, %a6 | %a6 = diff = s[pos] - last sub.l %d6, %a6 | 21: | movclr.l %acc0, %d7 | *d++ = %d7 = result move.l %d7, (%a4)+ | 22: | move.l %d6, %acc0 | %acc0 = last mac.l %d3, %a6, %acc0 | %acc0 += frac * diff subq.l #1, %d5 | dstrem <= 0? ble.b 23f | yes? stop add.l %d2, %d3 | phase += delta bpl.b 21b | load next values? move.l %a5, %d6 | bclr.l #31, %d3 | clear sign bit addq.l #1, %d0 | dte > 0? bmi.b 20b | yes? continue resampling tpf.w | trap next add.l (phase += delta) 23: | add.l %d2, %d3 | phase += delta lsl.l #1, %d3 | frac -> phase bcs.b 24f | was sign bit set? tpf.l | 24: | move.l %a5, %d6 | yes? was going to move to new s[pos] addq.l #1, %d0 | movclr.l %acc0, %d7 | *d = %d7 = result move.l %d7, (%a4) | add.l %d4, %d0 | %d0 = -dte + srcrem = pos or.l %d0, %d3 | restore phase swap.w %d3 | moveq.l #16, %d7 | %d7 = shift bra.b .lrs_channel_complete | | /** Downsampling **/ | .lrs_downsample: | move.l (%a3, %d0.l*4), %a5 | %a5 = s[pos] bra.b 31f | 30: | lea.l -4(%a3, %d0.l*4), %a5 | %d6 = s[pos - 1], %a5 = s[pos] movem.l (%a5), %d6/%a5 | 31: | move.l %d6, %acc0 | %acc0 = last sub.l %d6, %a5 | %a5 = diff = s[pos] - s[pos - 1] move.l %d3, %d0 | frac = (phase << 16) >> 1 lsl.l %d7, %d0 | lsr.l #1, %d0 | mac.l %d0, %a5, %acc0 | %acc0 += frac * diff add.l %d2, %d3 | phase += delta move.l %d3, %d0 | pos = phase >> 16 lsr.l %d7, %d0 | movclr.l %acc0, %a5 | move.l %a5, (%a4)+ | *d++ = %d0 subq.l #1, %d5 | dst full? ble.b 32f | yes? stop cmp.l %d4, %d0 | pos < srcrem? blt.b 30b | yes? continue resampling tpf.l | trap cmp.l and ble.b 32: | cmp.l %d4, %d0 | pos = MIN(pos, srcrem) ble.b 33f | move.l %d4, %d0 | 33: | move.l -4(%a3, %d0.l*4), %d6 | %d6 = s[pos - 1] | .lrs_channel_complete: | move.l %d6, 4(%a0, %d1.l*4) | last_sample[ch] = last subq.l #1, %d1 | ch > 0? bgt.w .lrs_channel_loop | yes? process next channel | move.l 12(%a2), %d1 | %d1 = dst->bufcount sub.l %d5, %d1 | written = dst->bufcount - dstrem move.l %d1, (%a2) | dst->remcount = written move.l %d0, %d1 | wrap phase to position in next frame lsl.l %d7, %d1 | data->phase = phase - (pos << 16) sub.l %d1, %d3 | ... move.l %d3, 4(%a0) | ... movem.l (%sp), %d2-%d7/%a2-%a6 | restore non-volatiles lea.l 44(%sp), %sp | cleanup stack rts | buh-bye .size lin_resample_resample, .-lin_resample_resample /**************************************************************************** * void channel_mode_proc_mono(struct dsp_proc_entry *this, * struct dsp_buffer **buf_p) * * Mix left and right channels 50/50 into a center channel. */ .section .text .align 2 .global channel_mode_proc_mono channel_mode_proc_mono: | input: 4(sp) = this, 8(sp) = buf_p move.l 8(%sp), %a0 | %a0 = buf_p move.l (%a0), %a0 | %a0 = buf = *buf_p lea.l -20(%sp), %sp | save registers movem.l %d2-%d4/%a2-%a3, (%sp) | movem.l (%a0), %d0/%a0-%a1 | %d0 = buf->remcount, %a0 = buf->p32[0], | %a1 = buf->p32[1] move.l %a0, %a2 | use separate dst pointers since read move.l %a1, %a3 | pointers run one ahead of write move.l #0x40000000, %d3 | %d3 = 0.5 move.l (%a0)+, %d1 | prime the input registers move.l (%a1)+, %d2 | mac.l %d1, %d3, (%a0)+, %d1, %acc0 | mac.l %d2, %d3, (%a1)+, %d2, %acc0 | subq.l #1, %d0 | ble.s 20f | loop done | 10: | loop | movclr.l %acc0, %d4 | L = R = l/2 + r/2 mac.l %d1, %d3, (%a0)+, %d1, %acc0 | mac.l %d2, %d3, (%a1)+, %d2, %acc0 | move.l %d4, (%a2)+ | output to original buffer move.l %d4, (%a3)+ | subq.l #1, %d0 | bgt.s 10b | loop | 20: | loop done | movclr.l %acc0, %d4 | output last sample move.l %d4, (%a2) | move.l %d4, (%a3) | movem.l (%sp), %d2-%d4/%a2-%a3 | restore registers lea.l 20(%sp), %sp | cleanup rts | .size channel_mode_proc_mono, .-channel_mode_proc_mono /**************************************************************************** * void channel_mode_proc_custom(struct dsp_proc_entry *this, * struct dsp_buffer **buf_p) * * Apply stereo width (narrowing/expanding) effect. */ .section .text .align 2 .global channel_mode_proc_custom channel_mode_proc_custom: | input: 4(sp) = this, 8(sp) = buf_p lea.l -28(%sp), %sp | save registers movem.l %d2-%d6/%a2-%a3, (%sp) | movem.l 32(%sp), %a0-%a1 | %a0 = this, %a1 = buf_p move.l (%a1), %a1 | %a1 = buf = *buf_p move.l (%a0), %a2 | %a2 = this->data = &channel_mode_data movem.l (%a1), %d0/%a0-%a1 | %d0 = buf->remcount, %a0 = buf->p32[0], | %a1 = buf->p32[1] movem.l (%a2), %d3-%d4 | %d3 = sw_gain, %d4 = sw_cross move.l %a0, %a2 | use separate dst pointers since read move.l %a1, %a3 | pointers run one ahead of write move.l (%a0)+, %d1 | prime the input registers move.l (%a1)+, %d2 | mac.l %d1, %d3 , %acc0 | L = l*gain + r*cross mac.l %d1, %d4, (%a0)+, %d1, %acc1 | R = r*gain + l*cross mac.l %d2, %d4 , %acc0 | mac.l %d2, %d3, (%a1)+, %d2, %acc1 | subq.l #1, %d0 | ble.b 20f | loop done | 10: | loop | movclr.l %acc0, %d5 | movclr.l %acc1, %d6 | mac.l %d1, %d3 , %acc0 | L = l*gain + r*cross mac.l %d1, %d4, (%a0)+, %d1, %acc1 | R = r*gain + l*cross mac.l %d2, %d4 , %acc0 | mac.l %d2, %d3, (%a1)+, %d2, %acc1 | move.l %d5, (%a2)+ | move.l %d6, (%a3)+ | subq.l #1, %d0 | bgt.s 10b | loop | 20: | loop done | movclr.l %acc0, %d5 | output last sample movclr.l %acc1, %d6 | move.l %d5, (%a2) | move.l %d6, (%a3) | movem.l (%sp), %d2-%d6/%a2-%a3 | restore registers lea.l 28(%sp), %sp | cleanup rts | .size channel_mode_proc_custom, .-channel_mode_proc_custom /**************************************************************************** * void channel_mode_proc_karaoke(struct dsp_proc_entry *this, * struct dsp_buffer **buf_p) * * Separate channels into side channels. */ .section .text .align 2 .global channel_mode_proc_karaoke channel_mode_proc_karaoke: | input: 4(sp) = this, 8(sp) = buf_p move.l 8(%sp), %a0 | %a0 = buf_p move.l (%a0), %a0 | %a0 = buf = *buf_p lea.l -20(%sp), %sp | save registers movem.l %d2-%d4/%a2-%a3, (%sp) | movem.l (%a0), %d0/%a0-%a1 | %d0 = buf->remcount, %a0 = buf->p32[0], | %a1 = buf->p32[1] move.l %a0, %a2 | use separate dst pointers since read move.l %a1, %a3 | pointers run one ahead of write move.l #0x40000000, %d3 | %d3 = 0.5 move.l (%a0)+, %d1 | prime the input registers move.l (%a1)+, %d2 | mac.l %d1, %d3, (%a0)+, %d1, %acc0 | L = l/2 - r/2 msac.l %d2, %d3, (%a1)+, %d2, %acc0 | subq.l #1, %d0 | ble.b 20f | loop done | 10: | loop | movclr.l %acc0, %d4 | mac.l %d1, %d3, (%a0)+, %d1, %acc0 | L = l/2 - r/2 msac.l %d2, %d3, (%a1)+, %d2, %acc0 | move.l %d4, (%a2)+ | neg.l %d4 | R = -L = -(l/2 - r/2) = r/2 - l/2 move.l %d4, (%a3)+ | subq.l #1, %d0 | bgt.s 10b | loop | 20: | loop done | movclr.l %acc0, %d4 | output last sample move.l %d4, (%a2) | neg.l %d4 | R = -L = -(l/2 - r/2) = r/2 - l/2 move.l %d4, (%a3) | movem.l (%sp), %d2-%d4/%a2-%a3 | restore registers lea.l 20(%sp), %sp | cleanup rts | .size channel_mode_proc_karaoke, .-channel_mode_proc_karaoke /**************************************************************************** * void filter_process(struct dsp_filter *f, int32_t *buf[], int count, * unsigned int channels) * * define HIGH_PRECISION as '1' to make filtering calculate lower bits after * shifting. without this, "shift" - 1 of the lower bits will be lost here. */ #define HIGH_PRECISION 0 .text .global filter_process filter_process: | input: 4(sp) = f, 8(sp) = buf, 12(sp) = count, 16(sp) = channels lea.l -44(%sp), %sp | save clobbered regs #if HIGH_PRECISION movem.l %d2-%d7/%a2-%a6, (%sp) | . #else movem.l %d2-%d6/%a2-%a6, (%sp) | #endif move.l 48(%sp), %a5 | fetch filter structure address clr.l %d6 | load shift count move.b 52(%a5), %d6 | . subq.l #1, %d6 | EMAC gives us one free shift #if HIGH_PRECISION moveq.l #8, %d7 sub.l %d6, %d7 | shift for lower part of accumulator #endif movem.l (%a5), %a0-%a4 | load coefs lea.l 20(%a5), %a5 | point to filter history 10: | channel loop move.l 52(%sp), %a6 | load input channel pointer addq.l #4, 52(%sp) | point x to next channel move.l (%a6), %a6 | move.l 56(%sp), %d5 | number of samples movem.l (%a5), %d0-%d3 | load filter history | d0-d3 = history, d4 = temp, d5 = sample count, d6 = upper shift amount, | d7 = lower shift amount,a0-a4 = coefs, a5 = history pointer, a6 = buf[ch] 20: | loop | Direct form 1 filtering code. We assume DSP has put EMAC in frac mode. | y[n] = b0*x[i] + b1*x[i - 1] + b2*x[i - 2] + a1*y[i - 1] + a2*y[i - 2], | where y[] is output and x[] is input. This is performed out of order | to do parallel load of input value. mac.l %a2, %d1, %acc0 | acc = b2*x[i - 2] move.l %d0, %d1 | fix input history mac.l %a1, %d0, (%a6), %d0, %acc0 | acc += b1*x[i - 1], x[i] -> d0 mac.l %a0, %d0, %acc0 | acc += b0*x[i] mac.l %a3, %d2, %acc0 | acc += a1*y[i - 1] mac.l %a4, %d3, %acc0 | acc += a2*y[i - 2] move.l %d2, %d3 | fix output history #if HIGH_PRECISION move.l %accext01, %d2 | fetch lower part of accumulator move.b %d2, %d4 | clear upper three bytes lsr.l %d7, %d4 | shift lower bits #endif movclr.l %acc0, %d2 | fetch upper part of result asl.l %d6, %d2 | restore fixed point format #if HIGH_PRECISION or.l %d2, %d4 | combine lower and upper parts #endif move.l %d2, (%a6)+ | save result subq.l #1, %d5 | are we done with this channel? bgt 20b | loop movem.l %d0-%d3, (%a5) | save history back to struct lea.l 16(%a5), %a5 | point to next channel's history subq.l #1, 60(%sp) | have we processed both channels? bhi 10b | channel loop #if HIGH_PRECISION movem.l (%sp), %d2-%d7/%a2-%a6 #else movem.l (%sp), %d2-%d6/%a2-%a6 #endif lea.l 44(%sp), %sp rts .size filter_process, .-filter_process /**************************************************************************** * void sample_output_stereo(struct sample_io_data *this, * struct dsp_buffer *src, * struct dsp_buffer *dst) * * Framework based on the ubiquitous Rockbox line transfer logic for * Coldfire CPUs. * * Does emac clamping and scaling (which proved faster than the usual * checks and branches - even single test clamping) and writes using * line burst transfers. Also better than writing a single L-R pair per * loop but a good deal more code. * * Attemping bursting during reads is rather futile since the source and * destination alignments rarely agree and too much complication will * slow us up. The parallel loads seem to do a bit better at least until * a pcm buffer can always give line aligned chunk and then aligning the * dest can then imply the source is aligned if the source buffers are. * For now longword alignment is assumed of both the source and dest. * */ .section .text .align 2 .global sample_output_stereo sample_output_stereo: | input: 4(sp) = count, 8(sp) = src, 12(sp) = dst lea.l -48(%sp), %sp | save registers move.l %macsr, %d1 | do it now as at many lines will movem.l %d1-%d7/%a2-%a6, (%sp) | be the far more common condition move.l #0x80, %macsr | put emac unit in signed int mode movem.l 52(%sp), %a0-%a2 | %a0 = this, %a1 = src, %a2 = dst move.l (%a0), %a0 | %a0 = this->outcount move.l 4(%a2), %a4 | %a4 = dst->p16out lea.l (%a4, %a0.l*4), %a0 | %a0 = count -> end address movem.l 4(%a1), %a2-%a3 | %a2 = src->p32[0], %a3 = src->p32[1] clr.l %d1 | %a1 = multiplier: (1 << (16 - scale)) move.b 19(%a1), %d1 | %d1 = src->format.output_scale sub.l #16, %d1 | neg.l %d1 | moveq.l #1, %d0 | asl.l %d1, %d0 | move.l %d0, %a1 | move.l #0x8000, %a6 | %a6 = rounding term moveq.l #28, %d0 | %d0 = second line bound add.l %a4, %d0 | and.l #0xfffffff0, %d0 | cmp.l %a0, %d0 | at least a full line? bhi.w 40f | long loop 1 start | no? do as trailing longwords sub.l #16, %d0 | %d1 = first line bound cmp.l %a4, %d0 | any leading longwords? bls.b 20f | line loop start | no? start line loop 10: | long loop 0 | move.l (%a2)+, %d1 | read longword from L and R move.l %a6, %acc0 | move.l %acc0, %acc1 | mac.l %d1, %a1, (%a3)+, %d2, %acc0 | shift L to high word mac.l %d2, %a1, %acc1 | shift R to high word movclr.l %acc0, %d1 | get possibly saturated results movclr.l %acc1, %d2 | swap.w %d2 | move R to low word move.w %d2, %d1 | interleave MS 16 bits of each move.l %d1, (%a4)+ | ...and write both cmp.l %a4, %d0 | bhi.b 10b | long loop 0 | 20: | line loop start | lea.l -12(%a0), %a5 | %a5 = at or just before last line bound 30: | line loop | move.l (%a3)+, %d4 | get next 4 R samples and scale move.l %a6, %acc0 | move.l %acc0, %acc1 | move.l %acc1, %acc2 | move.l %acc2, %acc3 | mac.l %d4, %a1, (%a3)+, %d5, %acc0 | with saturation mac.l %d5, %a1, (%a3)+, %d6, %acc1 | mac.l %d6, %a1, (%a3)+, %d7, %acc2 | mac.l %d7, %a1, (%a2)+, %d0, %acc3 | lea.l 16(%a4), %a4 | increment dest here, mitigate stalls movclr.l %acc0, %d4 | obtain R results movclr.l %acc1, %d5 | movclr.l %acc2, %d6 | movclr.l %acc3, %d7 | move.l %a6, %acc0 | move.l %acc0, %acc1 | move.l %acc1, %acc2 | move.l %acc2, %acc3 | mac.l %d0, %a1, (%a2)+, %d1, %acc0 | get next 4 L samples and scale mac.l %d1, %a1, (%a2)+, %d2, %acc1 | with saturation mac.l %d2, %a1, (%a2)+, %d3, %acc2 | mac.l %d3, %a1 , %acc3 | swap.w %d4 | a) interleave most significant... swap.w %d5 | swap.w %d6 | swap.w %d7 | movclr.l %acc0, %d0 | obtain L results movclr.l %acc1, %d1 | movclr.l %acc2, %d2 | movclr.l %acc3, %d3 | move.w %d4, %d0 | a) ... 16 bits of L and R move.w %d5, %d1 | move.w %d6, %d2 | move.w %d7, %d3 | movem.l %d0-%d3, -16(%a4) | write four stereo samples cmp.l %a4, %a5 | bhi.b 30b | line loop | 40: | long loop 1 start | cmp.l %a4, %a0 | any longwords left? bls.b 60f | output end | no? stop 50: | long loop 1 | move.l (%a2)+, %d1 | handle trailing longwords move.l %a6, %acc0 | move.l %acc0, %acc1 | mac.l %d1, %a1, (%a3)+, %d2, %acc0 | the same way as leading ones mac.l %d2, %a1, %acc1 | movclr.l %acc0, %d1 | movclr.l %acc1, %d2 | swap.w %d2 | move.w %d2, %d1 | move.l %d1, (%a4)+ | cmp.l %a4, %a0 | bhi.b 50b | long loop 1 60: | output end | movem.l (%sp), %d1-%d7/%a2-%a6 | restore registers move.l %d1, %macsr | lea.l 48(%sp), %sp | cleanup rts | .size sample_output_stereo, .-sample_output_stereo /**************************************************************************** * void sample_output_mono(struct sample_io_data *this, * struct dsp_buffer *src, * struct dsp_buffer *dst) * * Same treatment as sample_output_stereo but for one channel. */ .section .text .align 2 .global sample_output_mono sample_output_mono: | input: 4(sp) = count, 8(sp) = src, 12(sp) = dst lea.l -32(%sp), %sp | save registers move.l %macsr, %d1 | do it now as at many lines will movem.l %d1-%d5/%a2-%a4, (%sp) | be the far more common condition move.l #0x80, %macsr | put emac unit in signed int mode movem.l 36(%sp), %a0-%a2 | %a0 = this, %a1 = src, %a2 = dst move.l (%a0), %a0 | %a0 = this->outcount move.l 4(%a2), %a3 | %a3 = dst->p16out movem.l 4(%a1), %a2 | %a2 = src->p32[0] lea.l (%a3, %a0.l*4), %a0 | %a0 = count -> end address clr.l %d1 | %d5 = multiplier: (1 << (16 - scale)) move.b 19(%a1), %d1 | %d1 = src->format.output_scale sub.l #16, %d1 | neg.l %d1 | moveq.l #1, %d5 | asl.l %d1, %d5 | move.l #0x8000, %a4 | %a4 = rounding term moveq.l #28, %d0 | %d0 = second line bound add.l %a3, %d0 | and.l #0xfffffff0, %d0 | cmp.l %a0, %d0 | at least a full line? bhi.w 40f | long loop 1 start | no? do as trailing longwords sub.l #16, %d0 | %d1 = first line bound cmp.l %a3, %d0 | any leading longwords? bls.b 20f | line loop start | no? start line loop 10: | long loop 0 | move.l (%a2)+, %d1 | read longword from L and R move.l %a4, %acc0 | mac.l %d1, %d5, %acc0 | shift L to high word movclr.l %acc0, %d1 | get possibly saturated results move.l %d1, %d2 | swap.w %d2 | move R to low word move.w %d2, %d1 | duplicate single channel into move.l %d1, (%a3)+ | L and R cmp.l %a3, %d0 | bhi.b 10b | long loop 0 | 20: | line loop start | lea.l -12(%a0), %a1 | %a1 = at or just before last line bound 30: | line loop | move.l (%a2)+, %d0 | get next 4 L samples and scale move.l %a4, %acc0 | move.l %acc0, %acc1 | move.l %acc1, %acc2 | move.l %acc2, %acc3 | mac.l %d0, %d5, (%a2)+, %d1, %acc0 | with saturation mac.l %d1, %d5, (%a2)+, %d2, %acc1 | mac.l %d2, %d5, (%a2)+, %d3, %acc2 | mac.l %d3, %d5 , %acc3 | lea.l 16(%a3), %a3 | increment dest here, mitigate stalls movclr.l %acc0, %d0 | obtain results movclr.l %acc1, %d1 | movclr.l %acc2, %d2 | movclr.l %acc3, %d3 | move.l %d0, %d4 | duplicate single channel swap.w %d4 | into L and R move.w %d4, %d0 | move.l %d1, %d4 | swap.w %d4 | move.w %d4, %d1 | move.l %d2, %d4 | swap.w %d4 | move.w %d4, %d2 | move.l %d3, %d4 | swap.w %d4 | move.w %d4, %d3 | movem.l %d0-%d3, -16(%a3) | write four stereo samples cmp.l %a3, %a1 | bhi.b 30b | line loop | 40: | long loop 1 start | cmp.l %a3, %a0 | any longwords left? bls.b 60f | output end | no? stop 50: | loop loop 1 | move.l (%a2)+, %d1 | handle trailing longwords move.l %a4, %acc0 | mac.l %d1, %d5, %acc0 | the same way as leading ones movclr.l %acc0, %d1 | move.l %d1, %d2 | swap.w %d2 | move.w %d2, %d1 | move.l %d1, (%a3)+ | cmp.l %a3, %a0 | bhi.b 50b | long loop 1 | 60: | output end | movem.l (%sp), %d1-%d5/%a2-%a4 | restore registers move.l %d1, %macsr | lea.l 32(%sp), %sp | cleanup rts | .size sample_output_mono, .-sample_output_mono