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-rw-r--r--drivers/misc/echo/echo.c73
1 files changed, 0 insertions, 73 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)
{