/* * (C) Copyright 2003 * Wolfgang Denk, DENX Software Engineering, wd@denx.de. * * See file CREDITS for list of people who contributed to this * project. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation; either version 2 of * the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, * MA 02111-1307 USA */ #include <common.h> #include <asm/inca-ip.h> /******************************************************************************* * * get_cpuclk - returns the frequency of the CPU. * * Gets the value directly from the INCA-IP hardware. * * RETURNS: * 150.000.000 for 150 MHz * 133.333.333 for 133 MHz (= 400MHz/3) * 100.000.000 for 100 MHz (= 400MHz/4) * NOTE: * This functions should be used by the hardware driver to get the correct * frequency of the CPU. Don't use the macros, which are set to init the CPU * frequency in the ROM code. */ uint incaip_get_cpuclk (void) { /*-------------------------------------------------------------------------*/ /* CPU Clock Input Multiplexer (MUX I) */ /* Multiplexer MUX I selects the maximum input clock to the CPU. */ /*-------------------------------------------------------------------------*/ if (*((volatile ulong *) INCA_IP_CGU_CGU_MUXCR) & INCA_IP_CGU_CGU_MUXCR_MUXI) { /* MUX I set to 150 MHz clock */ return 150000000; } else { /* MUX I set to 100/133 MHz clock */ if (*((volatile ulong *) INCA_IP_CGU_CGU_DIVCR) & 0x40) { /* Division value is 1/3, maximum CPU operating */ /* frequency is 133.3 MHz */ return 133333333; } else { /* Division value is 1/4, maximum CPU operating */ /* frequency is 100 MHz */ return 100000000; } } } /******************************************************************************* * * get_fpiclk - returns the frequency of the FPI bus. * * Gets the value directly from the INCA-IP hardware. * * RETURNS: Frquency in Hz * * NOTE: * This functions should be used by the hardware driver to get the correct * frequency of the CPU. Don't use the macros, which are set to init the CPU * frequency in the ROM code. * The calculation for the */ uint incaip_get_fpiclk (void) { uint clkCPU; clkCPU = incaip_get_cpuclk (); switch (*((volatile ulong *) INCA_IP_CGU_CGU_DIVCR) & 0xC) { case 0x4: return clkCPU >> 1; /* devided by 2 */ break; case 0x8: return clkCPU >> 2; /* devided by 4 */ break; default: return clkCPU; break; } } int incaip_set_cpuclk (void) { extern void ebu_init(long); extern void cgu_init(long); extern void sdram_init(long); char tmp[64]; ulong cpuclk; if (getenv_r ("cpuclk", tmp, sizeof (tmp)) > 0) { cpuclk = simple_strtoul (tmp, NULL, 10) * 1000000; cgu_init (cpuclk); ebu_init (cpuclk); sdram_init (cpuclk); } return 0; }