/* * (C) Copyright 2001 * Wolfgang Denk, DENX Software Engineering, wd@denx.de. * * (C) Copyright 2002 * Gregory E. Allen, gallen@arlut.utexas.edu * Applied Research Laboratories, The University of Texas at Austin * * 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 <mpc824x.h> #include <asm/processor.h> DECLARE_GLOBAL_DATA_PTR; /* ------------------------------------------------------------------------- */ /* NOTE: This describes the proper use of this file. * * CONFIG_SYS_CLK_FREQ should be defined as the input frequency on * PCI_SYNC_IN . * * CONFIG_PLL_PCI_TO_MEM_MULTIPLIER is only required on MPC8240 * boards. It should be defined as the PCI to Memory Multiplier as * documented in the MPC8240 Hardware Specs. * * Other mpc824x boards don't need CONFIG_PLL_PCI_TO_MEM_MULTIPLIER * because they can determine it from the PCR. * * Gary Milliorn <gary.milliorn@motorola.com> (who should know since * he designed the Sandpoint) told us that the PCR is not in all revs * of the MPC8240 CPU, so it's not guaranteeable and we cannot do * away with CONFIG_PLL_PCI_TO_MEM_MULTIPLIER altogether. */ /* ------------------------------------------------------------------------- */ /* This gives the PCI to Memory multiplier times 10 */ /* The index is the value of PLL_CFG[0:4] */ /* This is documented in the MPC8240/5 Hardware Specs */ short pll_pci_to_mem_multiplier[] = { #if defined(CONFIG_MPC8240) 30, 30, 10, 10, 20, 10, 0, 10, 10, 0, 20, 0, 20, 0, 20, 0, 30, 0, 15, 0, 20, 0, 20, 0, 25, 0, 10, 0, 15, 15, 0, 0, #elif defined(CONFIG_MPC8245) 30, 30, 10, 10, 20, 10, 10, 10, 10, 20, 20, 15, 20, 15, 20, 30, 30, 40, 15, 40, 20, 25, 20, 40, 25, 20, 10, 20, 15, 15, 15, 0, #else #error Specific type of MPC824x must be defined (i.e. CONFIG_MPC8240) #endif }; #define CU824_PLL_STATE_REG 0xFE80002F #define PCR 0x800000E2 /* ------------------------------------------------------------------------- */ /* compute the memory bus clock frequency */ ulong get_bus_freq (ulong dummy) { unsigned char pll_cfg; #if defined(CONFIG_MPC8240) && !defined(CONFIG_CU824) return (CONFIG_SYS_CLK_FREQ) * (CONFIG_PLL_PCI_TO_MEM_MULTIPLIER); #elif defined(CONFIG_CU824) pll_cfg = *(volatile unsigned char *) (CU824_PLL_STATE_REG); pll_cfg &= 0x1f; #else CONFIG_READ_BYTE(PCR, pll_cfg); pll_cfg = (pll_cfg >> 3) & 0x1f; #endif return ((CONFIG_SYS_CLK_FREQ) * pll_pci_to_mem_multiplier[pll_cfg] + 5) / 10; } /* ------------------------------------------------------------------------- */ /* This gives the Memory to CPU Core multiplier times 10 */ /* The index is the value of PLLRATIO in HID1 */ /* This is documented in the MPC8240 Hardware Specs */ /* This is not documented for MPC8245 ? FIXME */ short pllratio_to_factor[] = { 0, 0, 0, 10, 20, 20, 25, 45, 30, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 10, 0, 0, 0, 45, 30, 0, 40, 0, 0, 0, 35, 0, }; /* compute the CPU and memory bus clock frequencies */ int get_clocks (void) { uint hid1 = mfspr(HID1); hid1 = (hid1 >> (32-5)) & 0x1f; gd->cpu_clk = (pllratio_to_factor[hid1] * get_bus_freq(0) + 5) / 10; gd->bus_clk = get_bus_freq(0); return (0); }