From 66ed6cca3f340f7a8a06d9272ae2ef8e96f0273d Mon Sep 17 00:00:00 2001 From: Andy Fleming Date: Mon, 23 Apr 2007 02:37:47 -0500 Subject: [PATCH] Reworked 85xx speed detection code Changed the code to read the registers and calculate the clock rates, rather than using a "switch" statement. Idea from Andrew Klossner Signed-off-by: Andy Fleming --- cpu/mpc85xx/speed.c | 44 ++++++++------------------------------------ 1 file changed, 8 insertions(+), 36 deletions(-) diff --git a/cpu/mpc85xx/speed.c b/cpu/mpc85xx/speed.c index ca81ee7352..12359a2d64 100644 --- a/cpu/mpc85xx/speed.c +++ b/cpu/mpc85xx/speed.c @@ -37,49 +37,21 @@ void get_sys_info (sys_info_t * sysInfo) { volatile immap_t *immap = (immap_t *)CFG_IMMR; volatile ccsr_gur_t *gur = &immap->im_gur; - uint plat_ratio,e500_ratio; + uint plat_ratio,e500_ratio,half_freqSystemBus; plat_ratio = (gur->porpllsr) & 0x0000003e; plat_ratio >>= 1; - switch(plat_ratio) { - case 0x02: - case 0x03: - case 0x04: - case 0x05: - case 0x06: - case 0x08: - case 0x09: - case 0x0a: - case 0x0c: - case 0x10: - sysInfo->freqSystemBus = plat_ratio * CONFIG_SYS_CLK_FREQ; - break; - default: - sysInfo->freqSystemBus = 0; - break; - } - + sysInfo->freqSystemBus = plat_ratio * CONFIG_SYS_CLK_FREQ; e500_ratio = (gur->porpllsr) & 0x003f0000; e500_ratio >>= 16; - switch(e500_ratio) { - case 0x04: - sysInfo->freqProcessor = 2*sysInfo->freqSystemBus; - break; - case 0x05: - sysInfo->freqProcessor = 5*sysInfo->freqSystemBus/2; - break; - case 0x06: - sysInfo->freqProcessor = 3*sysInfo->freqSystemBus; - break; - case 0x07: - sysInfo->freqProcessor = 7*sysInfo->freqSystemBus/2; - break; - default: - sysInfo->freqProcessor = 0; - break; - } + + /* Divide before multiply to avoid integer + * overflow for processor speeds above 2GHz */ + half_freqSystemBus = sysInfo->freqSystemBus/2; + sysInfo->freqProcessor = e500_ratio*half_freqSystemBus; } + int get_clocks (void) { sys_info_t sys_info; -- 2.25.1