Jean-Christophe PLAGNIOL-VILLARD wrote:
common/cmd_ide.c | 52 ++++++++++++++++++++++++++++++++++++++++++++++++++++ include/ata.h | 4 +++- 2 files changed, 55 insertions(+), 1 deletions(-)
diff --git a/common/cmd_ide.c b/common/cmd_ide.c index b4d9719..0e435a7 100644 --- a/common/cmd_ide.c +++ b/common/cmd_ide.c @@ -167,6 +167,10 @@ static void input_data(int dev, ulong *sect_buf, int words); static void output_data(int dev, ulong *sect_buf, int words); static void ident_cpy (unsigned char *dest, unsigned char *src, unsigned int len);
+#ifdef CONFIG_TUNE_PIO +int inline ide_set_piomode(int pio_mode); +#endif
#ifndef CFG_ATA_PORT_ADDR #define CFG_ATA_PORT_ADDR(port) (port) #endif @@ -838,6 +842,16 @@ __ide_inb(int dev, int port) unsigned char inline ide_inb(int dev, int port) __attribute__((weak, alias("__ide_inb")));
why not do this?
int inline ide_set_piomode(int pio_mode) __attribute__((weak));
#ifdef __PPC__ # ifdef CONFIG_AMIGAONEG3SE static void @@ -1054,6 +1068,10 @@ static void ide_ident (block_dev_desc_t *dev_desc) int do_retry = 0; #endif
+#ifdef CONFIG_TUNE_PIO
- int pio_mode;
+#endif
#if 0 int mode, cycle_time; #endif @@ -1169,6 +1187,40 @@ static void ide_ident (block_dev_desc_t *dev_desc) else dev_desc->removable = 0;
+#ifdef CONFIG_TUNE_PIO
- /* Mode 0 - 2 only, are directly determined by word 51. */
- pio_mode = iop->tPIO;
- if(pio_mode > 2) {
printf("WARNING: Invalid PIO (word 51 = %d).\n", pio_mode);pio_mode = 0; /* Force it to dead slow, and hope for the best... */- }
- /* Any CompactFlash Storage Card that supports PIO mode 3 or above
* shall set bit 1 of word 53 to one and support the fields contained* in words 64 through 70.*/- if(iop->field_valid & 0x02) {
/* Mode 3 and above are possible. Check in order from slow* to fast, so we wind up with the highest mode allowed.*/if(iop->eide_pio_modes & 0x01) {pio_mode = 3;}if(iop->eide_pio_modes & 0x02) {pio_mode = 4;}if((iop->cf_advanced_caps & 0x07) == 0x01) {pio_mode = 5;}if((iop->cf_advanced_caps & 0x07) == 0x02) {pio_mode = 6;}- }
- /* System-specific, depends on bus speeds, etc. */
if(ide_set_piomode) ide_set_piomode(pio_mode);
if no ide_set_piomode implementation is present gcc will drop it at compile time IIRC.
Best Regards, J.
At least on the x86, this generates an explicit test, even with -O2. The generated code looks something like this:
80483cd: b8 00 00 00 00 mov $0x0,%eax 80483d2: 85 c0 test %eax,%eax 80483d4: 74 0c je 80483e2 <main+0x32> 80483d6: c7 04 24 0a 00 00 00 movl $0xa,(%esp) 80483dd: e8 1e 7c fb f7 call 0 <_init-0x8048250>
Is there some explicit optimization flag that causes gcc to drop it at compile time?
I basically was following the style of the existing code regarding weak linkage. See for example the ide_outb() implementation. Also, I don't think your approach eliminates any ifdefs, because we still would not want to perform the pio_mode calculation unless we intended to use the result.
Steve