From 4328e3e5ef1ae3427a4f6863aa65916a68ec2dd9 Mon Sep 17 00:00:00 2001 From: Mike Frysinger Date: Thu, 11 Jun 2009 13:37:11 +0100 Subject: [PATCH] Blackfin SPORT UART: rewrite inline assembly Hopefuly the new version is easier to read, but in the process it declares proper clobber lists and better constraints so that GCC can do a better job at allocating free registers. Signed-off-by: Mike Frysinger Signed-off-by: Bryan Wu Signed-off-by: Alan Cox Signed-off-by: Linus Torvalds --- drivers/serial/bfin_sport_uart.c | 54 +++++++++++++++++++++------------------- 1 file changed, 29 insertions(+), 25 deletions(-) diff --git a/drivers/serial/bfin_sport_uart.c b/drivers/serial/bfin_sport_uart.c index 6687ccd..34b4ae0 100644 --- a/drivers/serial/bfin_sport_uart.c +++ b/drivers/serial/bfin_sport_uart.c @@ -101,15 +101,16 @@ static inline void tx_one_byte(struct sport_uart_port *up, unsigned int value) { pr_debug("%s value:%x\n", __func__, value); /* Place a Start and Stop bit */ - __asm__ volatile ( - "R2 = b#01111111100;\n\t" - "R3 = b#10000000001;\n\t" - "%0 <<= 2;\n\t" - "%0 = %0 & R2;\n\t" - "%0 = %0 | R3;\n\t" - :"=r"(value) - :"0"(value) - :"R2", "R3"); + __asm__ __volatile__ ( + "R2 = b#01111111100;" + "R3 = b#10000000001;" + "%0 <<= 2;" + "%0 = %0 & R2;" + "%0 = %0 | R3;" + : "=d"(value) + : "d"(value) + : "ASTAT", "R2", "R3" + ); pr_debug("%s value:%x\n", __func__, value); SPORT_PUT_TX(up, value); @@ -118,27 +119,30 @@ static inline void tx_one_byte(struct sport_uart_port *up, unsigned int value) static inline unsigned int rx_one_byte(struct sport_uart_port *up) { unsigned int value, extract; + u32 tmp_mask1, tmp_mask2, tmp_shift, tmp; value = SPORT_GET_RX32(up); pr_debug("%s value:%x\n", __func__, value); /* Extract 8 bits data */ - __asm__ volatile ( - "R5 = 0;\n\t" - "P0 = 8;\n\t" - "R1 = 0x1801(Z);\n\t" - "R3 = 0x0300(Z);\n\t" - "R4 = 0;\n\t" - "LSETUP(loop_s, loop_e) LC0 = P0;\nloop_s:\t" - "R2 = extract(%1, R1.L)(Z);\n\t" - "R2 <<= R4;\n\t" - "R5 = R5 | R2;\n\t" - "R1 = R1 - R3;\nloop_e:\t" - "R4 += 1;\n\t" - "%0 = R5;\n\t" - :"=r"(extract) - :"r"(value) - :"P0", "R1", "R2","R3","R4", "R5"); + __asm__ __volatile__ ( + "%[extr] = 0;" + "%[mask1] = 0x1801(Z);" + "%[mask2] = 0x0300(Z);" + "%[shift] = 0;" + "LSETUP(.Lloop_s, .Lloop_e) LC0 = %[lc];" + ".Lloop_s:" + "%[tmp] = extract(%[val], %[mask1].L)(Z);" + "%[tmp] <<= %[shift];" + "%[extr] = %[extr] | %[tmp];" + "%[mask1] = %[mask1] - %[mask2];" + ".Lloop_e:" + "%[shift] += 1;" + : [val]"=d"(value), [extr]"=d"(extract), [shift]"=d"(tmp_shift), [tmp]"=d"(tmp), + [mask1]"=d"(tmp_mask1), [mask2]"=d"(tmp_mask2) + : "d"(value), [lc]"a"(8) + : "ASTAT", "LB0", "LC0", "LT0" + ); pr_debug(" extract:%x\n", extract); return extract; -- 2.7.4