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>

1 files changed, 83 insertions, 0 deletions

diff --git a/arch/sh/boards/mach-sdk7786/nmi.c b/arch/sh/boards/mach-sdk7786/nmi.c
new file mode 100644
index 000000000000..edcfa1f568ba
--- /dev/null
+++ b/arch/sh/boards/mach-sdk7786/nmi.c
@@ -0,0 +1,83 @@
+/*
+ * 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);
+}