Add PIXIS FPGA support for MPC8641HPCN board.

Move the 8641HPCN's PIXIS code to the new directory
board/freescale/common/ as it will be shared by
future boards not in the same processor family.

Write a "pixis_reset" command that utilizes the FPGA
reset sequencer to support alternate soft-reset options
such as using the "alternate" flash bank, enabling
the watch dog, or choosing different CPU frequencies.

Add documentation for the pixis_reset to README.mpc8641hpcn.

Signed-off-by: Haiying Wang <haiying.wang@freescale.com>
Signed-off-by: Jon Loeliger <jdl@freescale.com>

2 files changed, 503 insertions, 0 deletions

diff --git a/board/freescale/common/pixis.c b/board/freescale/common/pixis.c
new file mode 100644
index 0000000..af98157
--- /dev/null
+++ b/board/freescale/common/pixis.c
@@ -0,0 +1,472 @@
+/*
+ * Copyright 2006 Freescale Semiconductor
+ * Jeff Brown
+ * Srikanth Srinivasan (srikanth.srinivasan@freescale.com)
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <common.h>
+#include <command.h>
+#include <watchdog.h>
+#include <asm/cache.h>
+
+#include "pixis.h"
+
+
+static ulong strfractoint(uchar *strptr);
+
+
+/*
+ * Simple board reset.
+ */
+void pixis_reset(void)
+{
+    out8(PIXIS_BASE + PIXIS_RST, 0);
+}
+
+
+/*
+ * Per table 27, page 58 of MPC8641HPCN spec.
+ */
+int set_px_sysclk(ulong sysclk)
+{
+	u8 sysclk_s, sysclk_r, sysclk_v, vclkh, vclkl, sysclk_aux;
+
+	switch (sysclk) {
+	case 33:
+		sysclk_s = 0x04;
+		sysclk_r = 0x04;
+		sysclk_v = 0x07;
+		sysclk_aux = 0x00;
+		break;
+	case 40:
+		sysclk_s = 0x01;
+		sysclk_r = 0x1F;
+		sysclk_v = 0x20;
+		sysclk_aux = 0x01;
+		break;
+	case 50:
+		sysclk_s = 0x01;
+		sysclk_r = 0x1F;
+		sysclk_v = 0x2A;
+		sysclk_aux = 0x02;
+		break;
+	case 66:
+		sysclk_s = 0x01;
+		sysclk_r = 0x04;
+		sysclk_v = 0x04;
+		sysclk_aux = 0x03;
+		break;
+	case 83:
+		sysclk_s = 0x01;
+		sysclk_r = 0x1F;
+		sysclk_v = 0x4B;
+		sysclk_aux = 0x04;
+		break;
+	case 100:
+		sysclk_s = 0x01;
+		sysclk_r = 0x1F;
+		sysclk_v = 0x5C;
+		sysclk_aux = 0x05;
+		break;
+	case 134:
+		sysclk_s = 0x06;
+		sysclk_r = 0x1F;
+		sysclk_v = 0x3B;
+		sysclk_aux = 0x06;
+		break;
+	case 166:
+		sysclk_s = 0x06;
+		sysclk_r = 0x1F;
+		sysclk_v = 0x4B;
+		sysclk_aux = 0x07;
+		break;
+	default:
+		printf("Unsupported SYSCLK frequency.\n");
+		return 0;
+	}
+
+	vclkh = (sysclk_s << 5) | sysclk_r;
+	vclkl = sysclk_v;
+
+	out8(PIXIS_BASE + PIXIS_VCLKH, vclkh);
+	out8(PIXIS_BASE + PIXIS_VCLKL, vclkl);
+
+	out8(PIXIS_BASE + PIXIS_AUX, sysclk_aux);
+
+	return 1;
+}
+
+
+int set_px_mpxpll(ulong mpxpll)
+{
+	u8 tmp;
+	u8 val;
+
+	switch (mpxpll) {
+	case 2:
+	case 4:
+	case 6:
+	case 8:
+	case 10:
+	case 12:
+	case 14:
+	case 16:
+		val = (u8) mpxpll;
+		break;
+	default:
+		printf("Unsupported MPXPLL ratio.\n");
+		return 0;
+	}
+
+	tmp = in8(PIXIS_BASE + PIXIS_VSPEED1);
+	tmp = (tmp & 0xF0) | (val & 0x0F);
+	out8(PIXIS_BASE + PIXIS_VSPEED1, tmp);
+
+	return 1;
+}
+
+
+int set_px_corepll(ulong corepll)
+{
+	u8 tmp;
+	u8 val;
+
+	switch ((int)corepll) {
+	case 20:
+		val = 0x08;
+		break;
+	case 25:
+		val = 0x0C;
+		break;
+	case 30:
+		val = 0x10;
+		break;
+	case 35:
+		val = 0x1C;
+		break;
+	case 40:
+		val = 0x14;
+		break;
+	case 45:
+		val = 0x0E;
+		break;
+	default:
+		printf("Unsupported COREPLL ratio.\n");
+		return 0;
+	}
+
+	tmp = in8(PIXIS_BASE + PIXIS_VSPEED0);
+	tmp = (tmp & 0xE0) | (val & 0x1F);
+	out8(PIXIS_BASE + PIXIS_VSPEED0, tmp);
+
+	return 1;
+}
+
+
+void read_from_px_regs(int set)
+{
+	u8 mask = 0x1C;
+	u8 tmp = in8(PIXIS_BASE + PIXIS_VCFGEN0);
+
+	if (set)
+		tmp = tmp | mask;
+	else
+		tmp = tmp & ~mask;
+	out8(PIXIS_BASE + PIXIS_VCFGEN0, tmp);
+}
+
+
+void read_from_px_regs_altbank(int set)
+{
+	u8 mask = 0x04;
+	u8 tmp = in8(PIXIS_BASE + PIXIS_VCFGEN1);
+
+	if (set)
+		tmp = tmp | mask;
+	else
+		tmp = tmp & ~mask;
+	out8(PIXIS_BASE + PIXIS_VCFGEN1, tmp);
+}
+
+
+void set_altbank(void)
+{
+	u8 tmp;
+
+	tmp = in8(PIXIS_BASE + PIXIS_VBOOT);
+	tmp ^= 0x40;
+
+	out8(PIXIS_BASE + PIXIS_VBOOT, tmp);
+}
+
+
+void set_px_go(void)
+{
+	u8 tmp;
+
+	tmp = in8(PIXIS_BASE + PIXIS_VCTL);
+	tmp = tmp & 0x1E;
+	out8(PIXIS_BASE + PIXIS_VCTL, tmp);
+
+	tmp = in8(PIXIS_BASE + PIXIS_VCTL);
+	tmp = tmp | 0x01;
+	out8(PIXIS_BASE + PIXIS_VCTL, tmp);
+}
+
+
+void set_px_go_with_watchdog(void)
+{
+	u8 tmp;
+
+	tmp = in8(PIXIS_BASE + PIXIS_VCTL);
+	tmp = tmp & 0x1E;
+	out8(PIXIS_BASE + PIXIS_VCTL, tmp);
+
+	tmp = in8(PIXIS_BASE + PIXIS_VCTL);
+	tmp = tmp | 0x09;
+	out8(PIXIS_BASE + PIXIS_VCTL, tmp);
+}
+
+
+int pixis_disable_watchdog_cmd(cmd_tbl_t *cmdtp,
+			       int flag, int argc, char *argv[])
+{
+	u8 tmp;
+
+	tmp = in8(PIXIS_BASE + PIXIS_VCTL);
+	tmp = tmp & 0x1E;
+	out8(PIXIS_BASE + PIXIS_VCTL, tmp);
+
+	/* setting VCTL[WDEN] to 0 to disable watch dog */
+	tmp = in8(PIXIS_BASE + PIXIS_VCTL);
+	tmp &= ~0x08;
+	out8(PIXIS_BASE + PIXIS_VCTL, tmp);
+
+	return 0;
+}
+
+U_BOOT_CMD(
+	   diswd, 1, 0, pixis_disable_watchdog_cmd,
+	   "diswd	- Disable watchdog timer \n",
+	   NULL);
+
+/*
+ * This function takes the non-integral cpu:mpx pll ratio
+ * and converts it to an integer that can be used to assign
+ * FPGA register values.
+ * input: strptr i.e. argv[2]
+ */
+
+static ulong strfractoint(uchar *strptr)
+{
+	int i, j, retval;
+	int mulconst;
+	int intarr_len = 0, decarr_len = 0, no_dec = 0;
+	ulong intval = 0, decval = 0;
+	uchar intarr[3], decarr[3];
+
+	/* Assign the integer part to intarr[]
+	 * If there is no decimal point i.e.
+	 * if the ratio is an integral value
+	 * simply create the intarr.
+	 */
+	i = 0;
+	while (strptr[i] != 46) {
+		if (strptr[i] == 0) {
+			no_dec = 1;
+			break;
+		}
+		intarr[i] = strptr[i];
+		i++;
+	}
+
+	/* Assign length of integer part to intarr_len. */
+	intarr_len = i;
+	intarr[i] = '\0';
+
+	if (no_dec) {
+		/* Currently needed only for single digit corepll ratios */
+		mulconst = 10;
+		decval = 0;
+	} else {
+		j = 0;
+		i++;		/* Skipping the decimal point */
+		while ((strptr[i] > 47) && (strptr[i] < 58)) {
+			decarr[j] = strptr[i];
+			i++;
+			j++;
+		}
+
+		decarr_len = j;
+		decarr[j] = '\0';
+
+		mulconst = 1;
+		for (i = 0; i < decarr_len; i++)
+			mulconst *= 10;
+		decval = simple_strtoul(decarr, NULL, 10);
+	}
+
+	intval = simple_strtoul(intarr, NULL, 10);
+	intval = intval * mulconst;
+
+	retval = intval + decval;
+
+	return retval;
+}
+
+
+int
+pixis_reset_cmd(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
+{
+	ulong val;
+	ulong corepll;
+
+	/*
+	 * No args is a simple reset request.
+	 */
+	if (argc <= 1) {
+		pixis_reset();
+		/* not reached */
+	}
+
+	if (strcmp(argv[1], "cf") == 0) {
+
+		/*
+		 * Reset with frequency changed:
+		 *    cf <SYSCLK freq> <COREPLL ratio> <MPXPLL ratio>
+		 */
+		if (argc < 5) {
+			puts(cmdtp->usage);
+			return 1;
+		}
+
+		read_from_px_regs(0);
+
+		val = set_px_sysclk(simple_strtoul(argv[2], NULL, 10));
+
+		corepll = strfractoint(argv[3]);
+		val = val + set_px_corepll(corepll);
+		val = val + set_px_mpxpll(simple_strtoul(argv[4], NULL, 10));
+		if (val == 3) {
+			puts("Setting registers VCFGEN0 and VCTL\n");
+			read_from_px_regs(1);
+			puts("Resetting board with values from ");
+			puts("VSPEED0, VSPEED1, VCLKH, and VCLKL \n");
+			set_px_go();
+		} else {
+			puts(cmdtp->usage);
+			return 1;
+		}
+
+		while (1) ;	/* Not reached */
+
+	} else if (strcmp(argv[1], "altbank") == 0) {
+
+		/*
+		 * Reset using alternate flash bank:
+		 */
+		if (argv[2] == 0) {
+			/*
+			 * Reset from alternate bank without changing
+			 * frequency and without watchdog timer enabled.
+			 *	altbank
+			 */
+			read_from_px_regs(0);
+			read_from_px_regs_altbank(0);
+			if (argc > 2) {
+				puts(cmdtp->usage);
+				return 1;
+			}
+			puts("Setting registers VCFGNE1, VBOOT, and VCTL\n");
+			set_altbank();
+			read_from_px_regs_altbank(1);
+			puts("Resetting board to boot from the other bank.\n");
+			set_px_go();
+
+		} else if (strcmp(argv[2], "cf") == 0) {
+			/*
+			 * Reset with frequency changed
+			 *    altbank cf <SYSCLK freq> <COREPLL ratio>
+			 *				<MPXPLL ratio>
+			 */
+			read_from_px_regs(0);
+			read_from_px_regs_altbank(0);
+			val = set_px_sysclk(simple_strtoul(argv[3], NULL, 10));
+			corepll = strfractoint(argv[4]);
+			val = val + set_px_corepll(corepll);
+			val = val + set_px_mpxpll(simple_strtoul(argv[5],
+								 NULL, 10));
+			if (val == 3) {
+				puts("Setting registers VCFGEN0, VCFGEN1, VBOOT, and VCTL\n");
+				set_altbank();
+				read_from_px_regs(1);
+				read_from_px_regs_altbank(1);
+				puts("Enabling watchdog timer on the FPGA\n");
+				puts("Resetting board with values from ");
+				puts("VSPEED0, VSPEED1, VCLKH and VCLKL ");
+				puts("to boot from the other bank.\n");
+				set_px_go_with_watchdog();
+			} else {
+				puts(cmdtp->usage);
+				return 1;
+			}
+
+			while (1) ;	/* Not reached */
+
+		} else if (strcmp(argv[2], "wd") == 0) {
+			/*
+			 * Reset from alternate bank without changing
+			 * frequencies but with watchdog timer enabled:
+			 *    altbank wd
+			 */
+			read_from_px_regs(0);
+			read_from_px_regs_altbank(0);
+			puts("Setting registers VCFGEN1, VBOOT, and VCTL\n");
+			set_altbank();
+			read_from_px_regs_altbank(1);
+			puts("Enabling watchdog timer on the FPGA\n");
+			puts("Resetting board to boot from the other bank.\n");
+			set_px_go_with_watchdog();
+			while (1) ;	/* Not reached */
+
+		} else {
+			puts(cmdtp->usage);
+			return 1;
+		}
+
+	} else {
+		puts(cmdtp->usage);
+		return 1;
+	}
+
+	return 0;
+}
+
+
+U_BOOT_CMD(
+	pixis_reset, CFG_MAXARGS, 1, pixis_reset_cmd,
+	"pixis_reset - Reset the board using the FPGA sequencer\n",
+	"    pixis_reset\n"
+	"    pixis_reset [altbank]\n"
+	"    pixis_reset altbank wd\n"
+	"    pixis_reset altbank cf <SYSCLK freq> <COREPLL ratio> <MPXPLL ratio>\n"
+	"    pixis_reset cf <SYSCLK freq> <COREPLL ratio> <MPXPLL ratio>\n"
+	);
diff --git a/board/freescale/common/pixis.h b/board/freescale/common/pixis.h
new file mode 100644
index 0000000..ff62a62
--- /dev/null
+++ b/board/freescale/common/pixis.h
@@ -0,0 +1,31 @@
+/*
+ * Copyright 2006 Freescale Semiconductor
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+extern void pixis_reset(void);
+extern int set_px_sysclk(ulong sysclk);
+extern int set_px_mpxpll(ulong mpxpll);
+extern int set_px_corepll(ulong corepll);
+extern void read_from_px_regs(int set);
+extern void read_from_px_regs_altbank(int set);
+extern void set_altbank(void);
+extern void set_px_go(void);
+extern void set_px_go_with_watchdog(void);