On Thu, 3 Apr 2014, Geert Uytterhoeven wrote:
On Thu, Apr 3, 2014 at 2:41 PM, Greg Ungerer <gregungerer00@xxxxxxxxx> wrote:-#ifdef CONFIG_PILOT +#if defined(CONFIG_PILOT) movew #0x2410, 0xfffff200 /* PLLCR */ +#elif defined(CONFIG_M68VZ328) + movew #0x2493, 0xfffff200 /* PLLCR */Would it be cleaner to have a defined value here instead? This moves the #ifdef'ery to just the PLLCR value, and keeps the code instructions here cleaner. So something like this at the top of this head.S: #if defined(CONFIG_PILOT) #define PLLCR 0x2410 #elif defined(CONFIG_M68VZ328) #define PLLCR 0x2493 #else #define PLLCR 0x2400 #endif and then just movew #PLLCR, 0xfffff200 /* PLLCR */
In this case, the #ifdef ... #elif ... #else ... #endif cascade is already present, so I wonder whether your way is in fact better here.
While I like this advice in general, I prefer to use a different name than "PLLCR" for this definition. One day someone may want to put "#define PLLCR 0xfffff200" in a header file...
It's defined in asm/MC68328.h: #define PLLCR_ADDR 0xfffff200 ... #define PLLCR_DISPLL 0x0008 /* Disable PLL */ #define PLLCR_CLKEN 0x0010 /* Clock (CLKO pin) enable */ #define PLLCR_SYSCLK_SEL_MASK 0x0700 /* System Clock Selection */ #define PLLCR_SYSCLK_SEL_SHIFT 8 #define PLLCR_PIXCLK_SEL_MASK 0x3800 /* LCD Clock Selection */ #define PLLCR_PIXCLK_SEL_SHIFT 11 Some bit name definitions are missing, i.e. #define PLLCR_PRESC1 0x0080 -- -- To unsubscribe from this list: send the line "unsubscribe linux-m68k" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
