devs/foxbox
1
0
Fork 0
forked from len0rd/rockbox
Code Pull requests Activity

Enable setting of global output samplerate on certain targets.

Browse source 
Replaces the NATIVE_FREQUENCY constant with a configurable frequency.

The user may select 48000Hz if the hardware supports it. The default is
still 44100Hz and the minimum is 44100Hz. The setting is located in the
playback settings, under "Frequency".

"Frequency" was duplicated in english.lang for now to avoid having to
fix every .lang file for the moment and throwing everything out of sync
because of the new play_frequency feature in features.txt. The next
cleanup should combine it with the one included for recording and
generalize the ID label.

If the hardware doesn't support 48000Hz, no setting will be available.

On particular hardware where very high rates are practical and desireable,
the upper bound can be extended by patching.

The PCM mixer can be configured to play at the full hardware frequency
range. The DSP core can configure to the hardware minimum up to the
maximum playback setting (some buffers must be reserved according to
the maximum rate).

If only 44100Hz is supported or possible on a given target for playback,
using the DSP and mixer at other samperates is possible if the hardware
offers them.

Change-Id: I6023cf0c0baa8bc6292b6919b4dd3618a6a25622
Reviewed-on: http://gerrit.rockbox.org/479
Reviewed-by: Michael Sevakis <jethead71@rockbox.org>
Tested-by: Michael Sevakis <jethead71@rockbox.org>
This commit is contained in:
Michael Sevakis 2013-05-23 13:58:51 -04:00
parent 00faabef5e
commit d37bf24d90
44 changed files with 677 additions and 230 deletions
Download patch file Download diff file Expand all files Collapse all files

82
lib/rbcodec/dsp/dsp_arm.S
View file

@ -196,55 +196,56 @@ crossfeed_process:
@ to keep the count on the stack :/
ldr r1, [r1] @ r1 = buf = *buf_p;
stmfd sp!, { r4-r11, lr } @ stack modified regs
ldr r12, [r1] @ r12 = buf->remcount
ldr r14, [r0] @ r14 = this->data = &crossfeed_state
ldmib r1, { r2-r3 } @ r2 = buf->p32[0], r3 = buf->p32[1]
ldmia r14!, { r4-r11 } @ load direct gain and filter data
add r0, r14, #13*2*4 @ calculate end of delay
stmfd sp!, { r0, r12 } @ stack end of delay adr, count and state
ldr r0, [r0] @ fetch current delay line address
ldr r0, [r0] @ r0 = this->data = &crossfeed_state
ldmia r1, { r1-r3 } @ r1 = buf->remcount, r2 = buf->p32[0],
@ r3 = buf->p32[1]
ldmia r0, { r4-r12, r14 } @ r4 = gain, r5-r7 = coeffs,
@ r8-r11 = history, r12 = index,
@ r14 = index_max
add r0, r0, #0x28 @ r0 = state->delay
stmfd sp!, { r0-r1, r14 } @ stack state->delay, count, index_max
/* Register usage in loop:
* r0 = &delay[index][0], r1 = accumulator high, r2 = buf->p32[0],
/* Register usage in loop:
* r0 = acc low/count, r1 = acc high, r2 = buf->p32[0],
* r3 = buf->p32[1], r4 = direct gain, r5-r7 = b0, b1, a1 (filter coefs),
* r8-r11 = filter history, r12 = temp, r14 = accumulator low
* r8 = dr[n-1], r9 = y_r[n-1], r10 = dl[n-1], r11 = y_l[n-1],
* r12 = index, r14 = scratch/index_max
*/
.cfloop:
smull r14, r1, r6, r8 @ acc = b1*dr[n - 1]
smlal r14, r1, r7, r9 @ acc += a1*y_l[n - 1]
ldr r8, [r0, #4] @ r8 = dr[n]
smlal r14, r1, r5, r8 @ acc += b0*dr[n]
mov r9, r1, lsl #1 @ fix format for filter history
ldr r12, [r2] @ load left input
smlal r14, r1, r4, r12 @ acc += gain*x_l[n]
mov r1, r1, lsl #1 @ fix format
smull r0, r1, r6, r8 @ acc = b1*dr[n - 1]
ldr r8, [r12, #4] @ r8 = dr[n]
smlal r0, r1, r7, r9 @ acc += a1*y_r[n - 1]
smlal r0, r1, r5, r8 @ acc += b0*dr[n]
ldr r14, [r2] @ load left input: x_l[n]
mov r9, r1, asl #1 @ fix format for filter history
smlal r0, r1, r4, r14 @ acc += gain*x_l[n]
mov r1, r1, asl #1 @ fix format
str r1, [r2], #4 @ save result
smull r14, r1, r6, r10 @ acc = b1*dl[n - 1]
smlal r14, r1, r7, r11 @ acc += a1*y_r[n - 1]
ldr r10, [r0] @ r10 = dl[n]
str r12, [r0], #4 @ save left input to delay line
smlal r14, r1, r5, r10 @ acc += b0*dl[n]
mov r11, r1, lsl #1 @ fix format for filter history
ldr r12, [r3] @ load right input
smlal r14, r1, r4, r12 @ acc += gain*x_r[n]
str r12, [r0], #4 @ save right input to delay line
mov r1, r1, lsl #1 @ fix format
ldmia sp, { r12, r14 } @ fetch delay line end addr and count from stack
smull r0, r1, r6, r10 @ acc = b1*dl[n - 1]
ldr r10, [r12] @ r10 = dl[n]
smlal r0, r1, r7, r11 @ acc += a1*y_l[n - 1]
smlal r0, r1, r5, r10 @ acc += b0*dl[n]
str r14, [r12], #4 @ save left input to delay line
ldr r14, [r3] @ load right input: x_r[n]
mov r11, r1, asl #1 @ fix format for filter history
smlal r0, r1, r4, r14 @ acc += gain*x_r[n]
str r14, [r12], #4 @ save right input to delay line
ldmib sp, { r0, r14 } @ fetch count and delay end
mov r1, r1, asl #1 @ fix format
str r1, [r3], #4 @ save result
cmp r0, r12 @ need to wrap to start of delay?
subhs r0, r12, #13*2*4 @ wrap back delay line ptr to start
cmp r12, r14 @ need to wrap to start of delay?
ldrhs r12, [sp] @ wrap delay index
subs r14, r14, #1 @ are we finished?
strgt r14, [sp, #4] @ nope, save count back to stack
subs r0, r0, #1 @ are we finished?
strgt r0, [sp, #4] @ save count to stack
bgt .cfloop
@ save data back to struct
str r0, [r12] @ save delay line index
sub r12, r12, #13*2*4 + 4*4 @ r12 = data->history
stmia r12, { r8-r11 } @ save filter history
add sp, sp, #8 @ remove temp variables from stack
ldr r0, [sp] @ fetch state->delay
sub r0, r0, #0x18 @ save filter history and delay index
stmia r0, { r8-r12 } @
add sp, sp, #12 @ remove temp variables from stack
ldmpc regs=r4-r11
.size crossfeed_process, .-crossfeed_process
@ -260,8 +261,7 @@ crossfeed_meier_process:
ldr r0, [r0] @ r0 = this->data = &crossfeed_state
stmfd sp!, { r4-r10, lr } @ stack non-volatile context
ldmia r1, { r1-r3 } @ r1 = buf->remcout, r2=p32[0], r3=p32[1]
add r0, r0, #16 @ r0 = &state->vcl
ldmia r0, { r4-r8 } @ r4 = vcl, r5 = vcr, r6 = vdiff
ldmib r0, { r4-r8 } @ r4 = vcl, r5 = vcr, r6 = vdiff
@ r7 = coef1, r8 = coef2
.cfm_loop:
ldr r12, [r2] @ r12 = lout
@ -285,7 +285,7 @@ crossfeed_meier_process:
sub r5, r5, r12 @ r5 = vcr -= res2
bgt .cfm_loop @ more samples?
stmia r0, { r4-r6 } @ save vcl, vcr, vdiff
stmib r0, { r4-r6 } @ save vcl, vcr, vdiff
ldmpc regs=r4-r10 @ restore non-volatile context, return
.size crossfeed_meier_process, .-crossfeed_meier_process