sh: mach-sdk7786: Handle baseboard NMI source selection.

The on-board NMI switch is routed through and mangled by the FPGA prior
to its delivery to the NMI pin, so add some glue for the various
configuration options. The default is to unmask it and enable all input
sources.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

arch/sh/boards/mach-sdk7786/Makefile

-obj-y	:= fpga.o irq.o setup.o
+obj-y	:= fpga.o irq.o nmi.o setup.o
 
 obj-$(CONFIG_GENERIC_GPIO)	+= gpio.o
 obj-$(CONFIG_HAVE_SRAM_POOL)	+= sram.o

arch/sh/boards/mach-sdk7786/nmi.c

+/*
+ * SDK7786 FPGA NMI Support.
+ *
+ * Copyright (C) 2010  Paul Mundt
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <mach/fpga.h>
+
+enum {
+	NMI_MODE_MANUAL,
+	NMI_MODE_AUX,
+	NMI_MODE_MASKED,
+	NMI_MODE_ANY,
+	NMI_MODE_UNKNOWN,
+};
+
+/*
+ * Default to the manual NMI switch.
+ */
+static unsigned int __initdata nmi_mode = NMI_MODE_ANY;
+
+static int __init nmi_mode_setup(char *str)
+{
+	if (!str)
+		return 0;
+
+	if (strcmp(str, "manual") == 0)
+		nmi_mode = NMI_MODE_MANUAL;
+	else if (strcmp(str, "aux") == 0)
+		nmi_mode = NMI_MODE_AUX;
+	else if (strcmp(str, "masked") == 0)
+		nmi_mode = NMI_MODE_MASKED;
+	else if (strcmp(str, "any") == 0)
+		nmi_mode = NMI_MODE_ANY;
+	else {
+		nmi_mode = NMI_MODE_UNKNOWN;
+		pr_warning("Unknown NMI mode %s\n", str);
+	}
+
+	printk("Set NMI mode to %d\n", nmi_mode);
+	return 0;
+}
+early_param("nmi_mode", nmi_mode_setup);
+
+void __init sdk7786_nmi_init(void)
+{
+	unsigned int source, mask, tmp;
+
+	switch (nmi_mode) {
+	case NMI_MODE_MANUAL:
+		source = NMISR_MAN_NMI;
+		mask = NMIMR_MAN_NMIM;
+		break;
+	case NMI_MODE_AUX:
+		source = NMISR_AUX_NMI;
+		mask = NMIMR_AUX_NMIM;
+		break;
+	case NMI_MODE_ANY:
+		source = NMISR_MAN_NMI | NMISR_AUX_NMI;
+		mask = NMIMR_MAN_NMIM | NMIMR_AUX_NMIM;
+		break;
+	case NMI_MODE_MASKED:
+	case NMI_MODE_UNKNOWN:
+	default:
+		source = mask = 0;
+		break;
+	}
+
+	/* Set the NMI source */
+	tmp = fpga_read_reg(NMISR);
+	tmp &= ~NMISR_MASK;
+	tmp |= source;
+	fpga_write_reg(tmp, NMISR);
+
+	/* And the IRQ masking */
+	fpga_write_reg(NMIMR_MASK ^ mask, NMIMR);
+}

arch/sh/boards/mach-sdk7786/setup.c

@@ -237,6 +237,7 @@ static void __init sdk7786_setup(char **cmdline_p)
 	pr_info("Renesas Technology Europe SDK7786 support:\n");
 
 	sdk7786_fpga_init();
+	sdk7786_nmi_init();
 
 	pr_info("\tPCB revision:\t%d\n", fpga_read_reg(PCBRR) & 0xf);
 

arch/sh/include/mach-sdk7786/mach/fpga.h

@@ -14,11 +14,16 @@
 #define INTTESTR	0x040
 #define SYSSR		0x050
 #define NRGPR		0x060
+
 #define NMISR		0x070
+#define  NMISR_MAN_NMI	BIT(0)
+#define  NMISR_AUX_NMI	BIT(1)
+#define  NMISR_MASK	(NMISR_MAN_NMI | NMISR_AUX_NMI)
 
 #define NMIMR		0x080
 #define  NMIMR_MAN_NMIM	BIT(0)	/* Manual NMI mask */
 #define  NMIMR_AUX_NMIM	BIT(1)	/* Auxiliary NMI mask */
+#define  NMIMR_MASK	(NMIMR_MAN_NMIM | NMIMR_AUX_NMIM)
 
 #define INTBSR		0x090
 #define INTBMR		0x0a0
@@ -126,6 +131,9 @@
 extern void __iomem *sdk7786_fpga_base;
 extern void sdk7786_fpga_init(void);
 
+/* arch/sh/boards/mach-sdk7786/nmi.c */
+extern void sdk7786_nmi_init(void);
+
 #define SDK7786_FPGA_REGADDR(reg)	(sdk7786_fpga_base + (reg))
 
 /*