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misc: Remove Blackfin DSP echo support

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Remove Blackfin DSP echo support

Signed-off-by: Aaron Wu <aaron.wu@analog.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
This commit is contained in:
Aaron Wu 2018-03-15 18:50:11 +08:00 committed by Arnd Bergmann
parent 64f5fdd951
commit dabad54949
2 changed files with 0 additions and 123 deletions
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73
drivers/misc/echo/echo.c
View File

@ -115,78 +115,6 @@
/* adapting coeffs using the traditional stochastic descent (N)LMS algorithm */
#ifdef __bfin__
static inline void lms_adapt_bg(struct oslec_state *ec, int clean, int shift)
{
int i;
int offset1;
int offset2;
int factor;
int exp;
int16_t *phist;
int n;
if (shift > 0)
factor = clean << shift;
else
factor = clean >> -shift;
/* Update the FIR taps */
offset2 = ec->curr_pos;
offset1 = ec->taps - offset2;
phist = &ec->fir_state_bg.history[offset2];
/* st: and en: help us locate the assembler in echo.s */
/* asm("st:"); */
n = ec->taps;
for (i = 0; i < n; i++) {
exp = *phist++ * factor;
ec->fir_taps16[1][i] += (int16_t) ((exp + (1 << 14)) >> 15);
}
/* asm("en:"); */
/* Note the asm for the inner loop above generated by Blackfin gcc
4.1.1 is pretty good (note even parallel instructions used):
R0 = W [P0++] (X);
R0 *= R2;
R0 = R0 + R3 (NS) ||
R1 = W [P1] (X) ||
nop;
R0 >>>= 15;
R0 = R0 + R1;
W [P1++] = R0;
A block based update algorithm would be much faster but the
above can't be improved on much. Every instruction saved in
the loop above is 2 MIPs/ch! The for loop above is where the
Blackfin spends most of it's time - about 17 MIPs/ch measured
with speedtest.c with 256 taps (32ms). Write-back and
Write-through cache gave about the same performance.
*/
}
/*
IDEAS for further optimisation of lms_adapt_bg():
1/ The rounding is quite costly. Could we keep as 32 bit coeffs
then make filter pluck the MS 16-bits of the coeffs when filtering?
However this would lower potential optimisation of filter, as I
think the dual-MAC architecture requires packed 16 bit coeffs.
2/ Block based update would be more efficient, as per comments above,
could use dual MAC architecture.
3/ Look for same sample Blackfin LMS code, see if we can get dual-MAC
packing.
4/ Execute the whole e/c in a block of say 20ms rather than sample
by sample. Processing a few samples every ms is inefficient.
*/
#else
static inline void lms_adapt_bg(struct oslec_state *ec, int clean, int shift)
{
int i;
@ -215,7 +143,6 @@ static inline void lms_adapt_bg(struct oslec_state *ec, int clean, int shift)
ec->fir_taps16[1][i] += (int16_t) ((exp + (1 << 14)) >> 15);
}
}
#endif
static inline int top_bit(unsigned int bits)
{

50
drivers/misc/echo/fir.h
View File

@ -27,14 +27,6 @@
#define _FIR_H_
/*
Blackfin NOTES & IDEAS:
A simple dot product function is used to implement the filter. This performs
just one MAC/cycle which is inefficient but was easy to implement as a first
pass. The current Blackfin code also uses an unrolled form of the filter
history to avoid 0 length hardware loop issues. This is wasteful of
memory.
Ideas for improvement:
1/ Rewrite filter for dual MAC inner loop. The issue here is handling
@ -94,21 +86,13 @@ static inline const int16_t *fir16_create(struct fir16_state_t *fir,
fir->taps = taps;
fir->curr_pos = taps - 1;
fir->coeffs = coeffs;
#if defined(__bfin__)
fir->history = kcalloc(2 * taps, sizeof(int16_t), GFP_KERNEL);
#else
fir->history = kcalloc(taps, sizeof(int16_t), GFP_KERNEL);
#endif
return fir->history;
}
static inline void fir16_flush(struct fir16_state_t *fir)
{
#if defined(__bfin__)
memset(fir->history, 0, 2 * fir->taps * sizeof(int16_t));
#else
memset(fir->history, 0, fir->taps * sizeof(int16_t));
#endif
}
static inline void fir16_free(struct fir16_state_t *fir)
@ -116,42 +100,9 @@ static inline void fir16_free(struct fir16_state_t *fir)
kfree(fir->history);
}
#ifdef __bfin__
static inline int32_t dot_asm(short *x, short *y, int len)
{
int dot;
len--;
__asm__("I0 = %1;\n\t"
"I1 = %2;\n\t"
"A0 = 0;\n\t"
"R0.L = W[I0++] || R1.L = W[I1++];\n\t"
"LOOP dot%= LC0 = %3;\n\t"
"LOOP_BEGIN dot%=;\n\t"
"A0 += R0.L * R1.L (IS) || R0.L = W[I0++] || R1.L = W[I1++];\n\t"
"LOOP_END dot%=;\n\t"
"A0 += R0.L*R1.L (IS);\n\t"
"R0 = A0;\n\t"
"%0 = R0;\n\t"
: "=&d"(dot)
: "a"(x), "a"(y), "a"(len)
: "I0", "I1", "A1", "A0", "R0", "R1"
);
return dot;
}
#endif
static inline int16_t fir16(struct fir16_state_t *fir, int16_t sample)
{
int32_t y;
#if defined(__bfin__)
fir->history[fir->curr_pos] = sample;
fir->history[fir->curr_pos + fir->taps] = sample;
y = dot_asm((int16_t *) fir->coeffs, &fir->history[fir->curr_pos],
fir->taps);
#else
int i;
int offset1;
int offset2;
@ -165,7 +116,6 @@ static inline int16_t fir16(struct fir16_state_t *fir, int16_t sample)
y += fir->coeffs[i] * fir->history[i - offset1];
for (; i >= 0; i--)
y += fir->coeffs[i] * fir->history[i + offset2];
#endif
if (fir->curr_pos <= 0)
fir->curr_pos = fir->taps;
fir->curr_pos--;