diff options
Diffstat (limited to 'drivers/misc')
-rw-r--r-- | drivers/misc/echo/echo.c | 73 | ||||
-rw-r--r-- | drivers/misc/echo/fir.h | 50 |
2 files changed, 0 insertions, 123 deletions
diff --git a/drivers/misc/echo/echo.c b/drivers/misc/echo/echo.c index 9597e9523cac..8a5adc0d2e88 100644 --- a/drivers/misc/echo/echo.c +++ b/drivers/misc/echo/echo.c @@ -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) { diff --git a/drivers/misc/echo/fir.h b/drivers/misc/echo/fir.h index 7b9fabf1fea5..4e0f365f0577 100644 --- a/drivers/misc/echo/fir.h +++ b/drivers/misc/echo/fir.h @@ -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--; |