diff options
Diffstat (limited to 'arch/powerpc/boot/ebony.c')
| -rw-r--r-- | arch/powerpc/boot/ebony.c | 129 |
1 files changed, 129 insertions, 0 deletions
diff --git a/arch/powerpc/boot/ebony.c b/arch/powerpc/boot/ebony.c new file mode 100644 index 000000000000..b1251ee7a102 --- /dev/null +++ b/arch/powerpc/boot/ebony.c @@ -0,0 +1,129 @@ +/* + * Copyright 2007 David Gibson, IBM Corporation. + * + * Based on earlier code: + * Copyright (C) Paul Mackerras 1997. + * + * Matt Porter <mporter@kernel.crashing.org> + * Copyright 2002-2005 MontaVista Software Inc. + * + * Eugene Surovegin <eugene.surovegin@zultys.com> or <ebs@ebshome.net> + * Copyright (c) 2003, 2004 Zultys Technologies + * + * 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. + */ +#include <stdarg.h> +#include <stddef.h> +#include "types.h" +#include "elf.h" +#include "string.h" +#include "stdio.h" +#include "page.h" +#include "ops.h" +#include "reg.h" +#include "dcr.h" +#include "44x.h" + +extern char _dtb_start[]; +extern char _dtb_end[]; + +static u8 *ebony_mac0, *ebony_mac1; + +/* Calculate 440GP clocks */ +void ibm440gp_fixup_clocks(unsigned int sysclk, unsigned int ser_clk) +{ + u32 sys0 = mfdcr(DCRN_CPC0_SYS0); + u32 cr0 = mfdcr(DCRN_CPC0_CR0); + u32 cpu, plb, opb, ebc, tb, uart0, uart1, m; + u32 opdv = CPC0_SYS0_OPDV(sys0); + u32 epdv = CPC0_SYS0_EPDV(sys0); + + if (sys0 & CPC0_SYS0_BYPASS) { + /* Bypass system PLL */ + cpu = plb = sysclk; + } else { + if (sys0 & CPC0_SYS0_EXTSL) + /* PerClk */ + m = CPC0_SYS0_FWDVB(sys0) * opdv * epdv; + else + /* CPU clock */ + m = CPC0_SYS0_FBDV(sys0) * CPC0_SYS0_FWDVA(sys0); + cpu = sysclk * m / CPC0_SYS0_FWDVA(sys0); + plb = sysclk * m / CPC0_SYS0_FWDVB(sys0); + } + + opb = plb / opdv; + ebc = opb / epdv; + + /* FIXME: Check if this is for all 440GP, or just Ebony */ + if ((mfpvr() & 0xf0000fff) == 0x40000440) + /* Rev. B 440GP, use external system clock */ + tb = sysclk; + else + /* Rev. C 440GP, errata force us to use internal clock */ + tb = cpu; + + if (cr0 & CPC0_CR0_U0EC) + /* External UART clock */ + uart0 = ser_clk; + else + /* Internal UART clock */ + uart0 = plb / CPC0_CR0_UDIV(cr0); + + if (cr0 & CPC0_CR0_U1EC) + /* External UART clock */ + uart1 = ser_clk; + else + /* Internal UART clock */ + uart1 = plb / CPC0_CR0_UDIV(cr0); + + printf("PPC440GP: SysClk = %dMHz (%x)\n\r", + (sysclk + 500000) / 1000000, sysclk); + + dt_fixup_cpu_clocks(cpu, tb, 0); + + dt_fixup_clock("/plb", plb); + dt_fixup_clock("/plb/opb", opb); + dt_fixup_clock("/plb/opb/ebc", ebc); + dt_fixup_clock("/plb/opb/serial@40000200", uart0); + dt_fixup_clock("/plb/opb/serial@40000300", uart1); +} + +static void ebony_fixups(void) +{ + // FIXME: sysclk should be derived by reading the FPGA registers + unsigned long sysclk = 33000000; + + ibm440gp_fixup_clocks(sysclk, 6 * 1843200); + ibm44x_fixup_memsize(); + dt_fixup_mac_addresses(ebony_mac0, ebony_mac1); +} + +#define SPRN_DBCR0 0x134 +#define DBCR0_RST_SYSTEM 0x30000000 + +static void ebony_exit(void) +{ + unsigned long tmp; + + asm volatile ( + "mfspr %0,%1\n" + "oris %0,%0,%2@h\n" + "mtspr %1,%0" + : "=&r"(tmp) : "i"(SPRN_DBCR0), "i"(DBCR0_RST_SYSTEM) + ); + +} + +void ebony_init(void *mac0, void *mac1) +{ + platform_ops.fixups = ebony_fixups; + platform_ops.exit = ebony_exit; + ebony_mac0 = mac0; + ebony_mac1 = mac1; + ft_init(_dtb_start, _dtb_end - _dtb_start, 32); + serial_console_init(); +} |