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authorJosh Boyer <jwboyer@linux.vnet.ibm.com>2008-09-03 21:01:39 -0400
committerJosh Boyer <jwboyer@linux.vnet.ibm.com>2008-10-17 10:31:19 -0400
commit94c73a8f97907116e294aa27a58151cc4500e6fa (patch)
tree84a9283b007fd0c783958d6df7d6a3e81d5c998f /arch/powerpc/boot/cuboot-acadia.c
parent8105fa88593c87f8aba0e7e829d7dc0ee94fe2cf (diff)
powerpc/40x: Add cuboot wrapper for Acadia board
This adds a cuboot wrapper for the AMCC PowerPC 405EZ Acadia board. The clocking code is derived from U-Boot, originally written by Stefan Roese. Signed-off-by: Josh Boyer <jwboyer@linux.ibm.com>
Diffstat (limited to 'arch/powerpc/boot/cuboot-acadia.c')
-rw-r--r--arch/powerpc/boot/cuboot-acadia.c174
1 files changed, 174 insertions, 0 deletions
diff --git a/arch/powerpc/boot/cuboot-acadia.c b/arch/powerpc/boot/cuboot-acadia.c
new file mode 100644
index 000000000000..0634aba6348a
--- /dev/null
+++ b/arch/powerpc/boot/cuboot-acadia.c
@@ -0,0 +1,174 @@
+/*
+ * Old U-boot compatibility for Acadia
+ *
+ * Author: Josh Boyer <jwboyer@linux.vnet.ibm.com>
+ *
+ * Copyright 2008 IBM Corporation
+ *
+ * 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 "io.h"
+#include "dcr.h"
+#include "stdio.h"
+#include "4xx.h"
+#include "44x.h"
+#include "cuboot.h"
+
+#define TARGET_4xx
+#include "ppcboot.h"
+
+static bd_t bd;
+
+#define CPR_PERD0_SPIDV_MASK 0x000F0000 /* SPI Clock Divider */
+
+#define PLLC_SRC_MASK 0x20000000 /* PLL feedback source */
+
+#define PLLD_FBDV_MASK 0x1F000000 /* PLL feedback divider value */
+#define PLLD_FWDVA_MASK 0x000F0000 /* PLL forward divider A value */
+#define PLLD_FWDVB_MASK 0x00000700 /* PLL forward divider B value */
+
+#define PRIMAD_CPUDV_MASK 0x0F000000 /* CPU Clock Divisor Mask */
+#define PRIMAD_PLBDV_MASK 0x000F0000 /* PLB Clock Divisor Mask */
+#define PRIMAD_OPBDV_MASK 0x00000F00 /* OPB Clock Divisor Mask */
+#define PRIMAD_EBCDV_MASK 0x0000000F /* EBC Clock Divisor Mask */
+
+#define PERD0_PWMDV_MASK 0xFF000000 /* PWM Divider Mask */
+#define PERD0_SPIDV_MASK 0x000F0000 /* SPI Divider Mask */
+#define PERD0_U0DV_MASK 0x0000FF00 /* UART 0 Divider Mask */
+#define PERD0_U1DV_MASK 0x000000FF /* UART 1 Divider Mask */
+
+static void get_clocks(void)
+{
+ unsigned long sysclk, cpr_plld, cpr_pllc, cpr_primad, plloutb, i;
+ unsigned long pllFwdDiv, pllFwdDivB, pllFbkDiv, pllPlbDiv, pllExtBusDiv;
+ unsigned long pllOpbDiv, freqEBC, freqUART, freqOPB;
+ unsigned long div; /* total divisor udiv * bdiv */
+ unsigned long umin; /* minimum udiv */
+ unsigned short diff; /* smallest diff */
+ unsigned long udiv; /* best udiv */
+ unsigned short idiff; /* current diff */
+ unsigned short ibdiv; /* current bdiv */
+ unsigned long est; /* current estimate */
+ unsigned long baud;
+ void *np;
+
+ /* read the sysclk value from the CPLD */
+ sysclk = (in_8((unsigned char *)0x80000000) == 0xc) ? 66666666 : 33333000;
+
+ /*
+ * Read PLL Mode registers
+ */
+ cpr_plld = CPR0_READ(DCRN_CPR0_PLLD);
+ cpr_pllc = CPR0_READ(DCRN_CPR0_PLLC);
+
+ /*
+ * Determine forward divider A
+ */
+ pllFwdDiv = ((cpr_plld & PLLD_FWDVA_MASK) >> 16);
+
+ /*
+ * Determine forward divider B
+ */
+ pllFwdDivB = ((cpr_plld & PLLD_FWDVB_MASK) >> 8);
+ if (pllFwdDivB == 0)
+ pllFwdDivB = 8;
+
+ /*
+ * Determine FBK_DIV.
+ */
+ pllFbkDiv = ((cpr_plld & PLLD_FBDV_MASK) >> 24);
+ if (pllFbkDiv == 0)
+ pllFbkDiv = 256;
+
+ /*
+ * Read CPR_PRIMAD register
+ */
+ cpr_primad = CPR0_READ(DCRN_CPR0_PRIMAD);
+
+ /*
+ * Determine PLB_DIV.
+ */
+ pllPlbDiv = ((cpr_primad & PRIMAD_PLBDV_MASK) >> 16);
+ if (pllPlbDiv == 0)
+ pllPlbDiv = 16;
+
+ /*
+ * Determine EXTBUS_DIV.
+ */
+ pllExtBusDiv = (cpr_primad & PRIMAD_EBCDV_MASK);
+ if (pllExtBusDiv == 0)
+ pllExtBusDiv = 16;
+
+ /*
+ * Determine OPB_DIV.
+ */
+ pllOpbDiv = ((cpr_primad & PRIMAD_OPBDV_MASK) >> 8);
+ if (pllOpbDiv == 0)
+ pllOpbDiv = 16;
+
+ /* There is a bug in U-Boot that prevents us from using
+ * bd.bi_opbfreq because U-Boot doesn't populate it for
+ * 405EZ. We get to calculate it, yay!
+ */
+ freqOPB = (sysclk *pllFbkDiv) /pllOpbDiv;
+
+ freqEBC = (sysclk * pllFbkDiv) / pllExtBusDiv;
+
+ plloutb = ((sysclk * ((cpr_pllc & PLLC_SRC_MASK) ?
+ pllFwdDivB : pllFwdDiv) *
+ pllFbkDiv) / pllFwdDivB);
+
+ np = find_node_by_alias("serial0");
+ if (getprop(np, "current-speed", &baud, sizeof(baud)) != sizeof(baud))
+ fatal("no current-speed property\n\r");
+
+ udiv = 256; /* Assume lowest possible serial clk */
+ div = plloutb / (16 * baud); /* total divisor */
+ umin = (plloutb / freqOPB) << 1; /* 2 x OPB divisor */
+ diff = 256; /* highest possible */
+
+ /* i is the test udiv value -- start with the largest
+ * possible (256) to minimize serial clock and constrain
+ * search to umin.
+ */
+ for (i = 256; i > umin; i--) {
+ ibdiv = div / i;
+ est = i * ibdiv;
+ idiff = (est > div) ? (est-div) : (div-est);
+ if (idiff == 0) {
+ udiv = i;
+ break; /* can't do better */
+ } else if (idiff < diff) {
+ udiv = i; /* best so far */
+ diff = idiff; /* update lowest diff*/
+ }
+ }
+ freqUART = plloutb / udiv;
+
+ dt_fixup_cpu_clocks(bd.bi_procfreq, bd.bi_intfreq, bd.bi_plb_busfreq);
+ dt_fixup_clock("/plb/ebc", freqEBC);
+ dt_fixup_clock("/plb/opb", freqOPB);
+ dt_fixup_clock("/plb/opb/serial@ef600300", freqUART);
+ dt_fixup_clock("/plb/opb/serial@ef600400", freqUART);
+}
+
+static void acadia_fixups(void)
+{
+ dt_fixup_memory(bd.bi_memstart, bd.bi_memsize);
+ get_clocks();
+ dt_fixup_mac_address_by_alias("ethernet0", bd.bi_enetaddr);
+}
+
+void platform_init(unsigned long r3, unsigned long r4, unsigned long r5,
+ unsigned long r6, unsigned long r7)
+{
+ CUBOOT_INIT();
+ platform_ops.fixups = acadia_fixups;
+ platform_ops.exit = ibm40x_dbcr_reset;
+ fdt_init(_dtb_start);
+ serial_console_init();
+}