On Tue, 14 Dec 2021 12:12:34 +0100 Pali Rohár pali@kernel.org wrote:
On Tuesday 14 December 2021 10:45:15 Marek Behún wrote:
On Tue, 14 Dec 2021 10:36:00 +0100 Pali Rohár pali@kernel.org wrote:
On Friday 26 November 2021 15:37:37 Marek Behún wrote:
@@ -340,17 +333,17 @@ void board_init_f(ulong dummy) timer_init();
/* Armada 375 does not support SerDes and DDR3 init yet */ -#if !defined(CONFIG_ARMADA_375)
- /* First init the serdes PHY's */
- serdes_phy_config();
- /* Setup DDR */
- ret = ddr3_init();
- if (ret) {
debug("ddr3_init() failed: %d\n", ret);hang();
- if (!IS_ENABLED(CONFIG_ARMADA_375)) {
/* First init the serdes PHY's */serdes_phy_config();/* Setup DDR */ret = ddr3_init();if (ret) {debug("ddr3_init() failed: %d\n", ret);hang();}-#endif
As written in comment above there is no SerDes and DDR3 support for Armada 375 and therefore there is no serdes_phy_config() or ddr3_init() function. So this code needs not to be compiled at all and usage of #ifdef is correct here.
#ifdefs are almost never correct in C-files, for the parts of the code they guard isn't put through syntactic analysis, and can therefore contain bugs which we are not warned about.
Using if (IS_ENABLED()) almost never producess a different binary, because the code is optimized away.
Marek
There is no function serdes_phy_config() for Armada 375, so if you put it outside of #ifdef you will get compile error.
The function is always declared in arch/arm/mach-mvebu/include/mach/cpu.h regardless of architecture.
Thus an error will be raised only when linking, and the compliation was done with -O0, which I don't think anyone does.
Anyway, if we want to support -O0, this can and should be solved via defining serdes_phy_config() as empty static inline function in the cpu.h header, guarded by #ifdef. In header files #ifdefs are allowed, in this manner: #if X declare function #else define that function as empty static inline #endif
So if you think we should support -O0, I can do this.
But the #ifdefs should really go away from real C code, that is the way both Linux and U-Boot are trying to go for the last couple of years, if I understand it correctly.
Marek