csky: Exception handling and mm-fault

This patch adds exception handling code, cpuinfo and mm-fault code.

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>

1 files changed, 79 insertions, 0 deletions

diff --git a/arch/csky/kernel/cpu-probe.c b/arch/csky/kernel/cpu-probe.c
new file mode 100644
index 000000000000..5f15ca31d3e8
--- /dev/null
+++ b/arch/csky/kernel/cpu-probe.c
@@ -0,0 +1,79 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#include <linux/of.h>
+#include <linux/init.h>
+#include <linux/seq_file.h>
+#include <linux/memblock.h>
+
+#include <abi/reg_ops.h>
+
+static void percpu_print(void *arg)
+{
+	struct seq_file *m = (struct seq_file *)arg;
+	unsigned int cur, next, i;
+
+	seq_printf(m, "processor       : %d\n", smp_processor_id());
+	seq_printf(m, "C-SKY CPU model : %s\n", CSKYCPU_DEF_NAME);
+
+	/* read processor id, max is 100 */
+	cur  = mfcr("cr13");
+	for (i = 0; i < 100; i++) {
+		seq_printf(m, "product info[%d] : 0x%08x\n", i, cur);
+
+		next = mfcr("cr13");
+
+		/* some CPU only has one id reg */
+		if (cur == next)
+			break;
+
+		cur = next;
+
+		/* cpid index is 31-28, reset */
+		if (!(next >> 28)) {
+			while ((mfcr("cr13") >> 28) != i);
+			break;
+		}
+	}
+
+	/* CPU feature regs, setup by bootloader or gdbinit */
+	seq_printf(m, "hint (CPU funcs): 0x%08x\n", mfcr_hint());
+	seq_printf(m, "ccr  (L1C & MMU): 0x%08x\n", mfcr("cr18"));
+	seq_printf(m, "ccr2 (L2C)      : 0x%08x\n", mfcr_ccr2());
+	seq_printf(m, "\n");
+}
+
+static int c_show(struct seq_file *m, void *v)
+{
+	int cpu;
+
+	for_each_online_cpu(cpu)
+		smp_call_function_single(cpu, percpu_print, m, true);
+
+#ifdef CSKY_ARCH_VERSION
+	seq_printf(m, "arch-version : %s\n", CSKY_ARCH_VERSION);
+	seq_printf(m, "\n");
+#endif
+
+	return 0;
+}
+
+static void *c_start(struct seq_file *m, loff_t *pos)
+{
+	return *pos < 1 ? (void *)1 : NULL;
+}
+
+static void *c_next(struct seq_file *m, void *v, loff_t *pos)
+{
+	++*pos;
+	return NULL;
+}
+
+static void c_stop(struct seq_file *m, void *v) {}
+
+const struct seq_operations cpuinfo_op = {
+	.start	= c_start,
+	.next	= c_next,
+	.stop	= c_stop,
+	.show	= c_show,
+};