android_kernel_xiaomi_sm8350/arch/powerpc/boot/treeboot-walnut.c
Josh Boyer 094624fa66 [POWERPC] 4xx: Fix timebase clock selection on Walnut
The current bootwrapper fails to set the timebase clock to the CPU clock
which causes the time to increment incorrectly.  This fixes it by using the
correct #define for the CPC0_CR1 register.

Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
2007-10-19 16:18:31 -05:00

132 lines
3.3 KiB
C

/*
* Old U-boot compatibility for Walnut
*
* Author: Josh Boyer <jwboyer@linux.vnet.ibm.com>
*
* Copyright 2007 IBM Corporation
* Based on cuboot-83xx.c, which is:
* Copyright (c) 2007 Freescale Semiconductor, Inc.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published
* by the Free Software Foundation.
*/
#include "ops.h"
#include "stdio.h"
#include "dcr.h"
#include "4xx.h"
#include "io.h"
BSS_STACK(4096);
void ibm405gp_fixup_clocks(unsigned int sysclk, unsigned int ser_clk)
{
u32 pllmr = mfdcr(DCRN_CPC0_PLLMR);
u32 cpc0_cr0 = mfdcr(DCRN_405_CPC0_CR0);
u32 cpc0_cr1 = mfdcr(DCRN_405_CPC0_CR1);
u32 cpu, plb, opb, ebc, tb, uart0, uart1, m;
u32 fwdv, fbdv, cbdv, opdv, epdv, udiv;
fwdv = (8 - ((pllmr & 0xe0000000) >> 29));
fbdv = (pllmr & 0x1e000000) >> 25;
cbdv = ((pllmr & 0x00060000) >> 17) + 1;
opdv = ((pllmr & 0x00018000) >> 15) + 1;
epdv = ((pllmr & 0x00001800) >> 13) + 2;
udiv = ((cpc0_cr0 & 0x3e) >> 1) + 1;
m = fwdv * fbdv * cbdv;
cpu = sysclk * m / fwdv;
plb = cpu / cbdv;
opb = plb / opdv;
ebc = plb / epdv;
if (cpc0_cr0 & 0x80) {
/* uart0 uses the external clock */
uart0 = ser_clk;
} else {
uart0 = cpu / udiv;
}
if (cpc0_cr0 & 0x40) {
/* uart1 uses the external clock */
uart1 = ser_clk;
} else {
uart1 = cpu / udiv;
}
/* setup the timebase clock to tick at the cpu frequency */
cpc0_cr1 = cpc0_cr1 & ~0x00800000;
mtdcr(DCRN_405_CPC0_CR1, cpc0_cr1);
tb = cpu;
dt_fixup_cpu_clocks(cpu, tb, 0);
dt_fixup_clock("/plb", plb);
dt_fixup_clock("/plb/opb", opb);
dt_fixup_clock("/plb/ebc", ebc);
dt_fixup_clock("/plb/opb/serial@ef600300", uart0);
dt_fixup_clock("/plb/opb/serial@ef600400", uart1);
}
static void walnut_flashsel_fixup(void)
{
void *devp, *sram;
u32 reg_flash[3] = {0x0, 0x0, 0x80000};
u32 reg_sram[3] = {0x0, 0x0, 0x80000};
u8 *fpga;
u8 fpga_brds1 = 0x0;
devp = finddevice("/plb/ebc/fpga");
if (!devp)
fatal("Couldn't locate FPGA node\n\r");
if (getprop(devp, "virtual-reg", &fpga, sizeof(fpga)) != sizeof(fpga))
fatal("no virtual-reg property\n\r");
fpga_brds1 = in_8(fpga);
devp = finddevice("/plb/ebc/flash");
if (!devp)
fatal("Couldn't locate flash node\n\r");
if (getprop(devp, "reg", reg_flash, sizeof(reg_flash)) != sizeof(reg_flash))
fatal("flash reg property has unexpected size\n\r");
sram = finddevice("/plb/ebc/sram");
if (!sram)
fatal("Couldn't locate sram node\n\r");
if (getprop(sram, "reg", reg_sram, sizeof(reg_sram)) != sizeof(reg_sram))
fatal("sram reg property has unexpected size\n\r");
if (fpga_brds1 & 0x1) {
reg_flash[1] ^= 0x80000;
reg_sram[1] ^= 0x80000;
}
setprop(devp, "reg", reg_flash, sizeof(reg_flash));
setprop(sram, "reg", reg_sram, sizeof(reg_sram));
}
static void walnut_fixups(void)
{
ibm4xx_fixup_memsize();
ibm405gp_fixup_clocks(33330000, 0xa8c000);
ibm4xx_quiesce_eth((u32 *)0xef600800, NULL);
ibm4xx_fixup_ebc_ranges("/plb/ebc");
walnut_flashsel_fixup();
}
void platform_init(void)
{
unsigned long end_of_ram = 0x2000000;
unsigned long avail_ram = end_of_ram - (unsigned long) _end;
simple_alloc_init(_end, avail_ram, 32, 32);
platform_ops.fixups = walnut_fixups;
platform_ops.exit = ibm40x_dbcr_reset;
ft_init(_dtb_start, _dtb_end - _dtb_start, 32);
serial_console_init();
}