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>

diff --git a/arch/powerpc/boot/Makefile b/arch/powerpc/boot/Makefile
index aac1406..4760365 100644 (file)
--- a/arch/powerpc/boot/Makefile
+++ b/arch/powerpc/boot/Makefile
@@ -68,7 +68,8 @@ src-plat := of.c cuboot-52xx.c cuboot-824x.c cuboot-83xx.c cuboot-85xx.c holly.c
                fixed-head.S ep88xc.c ep405.c cuboot-c2k.c \
                cuboot-katmai.c cuboot-rainier.c redboot-8xx.c ep8248e.c \
                cuboot-warp.c cuboot-85xx-cpm2.c cuboot-yosemite.c simpleboot.c \
-               virtex405-head.S virtex.c redboot-83xx.c cuboot-sam440ep.c
+               virtex405-head.S virtex.c redboot-83xx.c cuboot-sam440ep.c \
+               cuboot-acadia.c
 src-boot := $(src-wlib) $(src-plat) empty.c
 
 src-boot := $(addprefix $(obj)/, $(src-boot))
@@ -211,6 +212,7 @@ image-$(CONFIG_DEFAULT_UIMAGE)              += uImage
 # Board ports in arch/powerpc/platform/40x/Kconfig
 image-$(CONFIG_EP405)                  += dtbImage.ep405
 image-$(CONFIG_WALNUT)                 += treeImage.walnut
+image-$(CONFIG_ACADIA)                 += cuImage.acadia
 
 # Board ports in arch/powerpc/platform/44x/Kconfig
 image-$(CONFIG_EBONY)                  += treeImage.ebony cuImage.ebony

diff --git a/arch/powerpc/boot/cuboot-acadia.c b/arch/powerpc/boot/cuboot-acadia.c
new file mode 100644 (file)
index 0000000..0634aba
--- /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();
+}