aboutsummaryrefslogtreecommitdiff
path: root/arch/powerpc/boot/ebony.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/powerpc/boot/ebony.c')
-rw-r--r--arch/powerpc/boot/ebony.c129
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 00000000000..b1251ee7a10
--- /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();
+}