From d3b41b6bb49ecbf74b6bda63e00bf17fdb4d3c47 Mon Sep 17 00:00:00 2001
From: Finn Thain <fthain@telegraphics.com.au>
Date: Tue, 15 Jan 2019 15:18:56 +1100
Subject: m68k: Dispatch nvram_ops calls to Atari or Mac functions

A multi-platform kernel binary has to decide at run-time how to dispatch
the arch_nvram_ops calls. Add a platform-independent arch_nvram_ops
struct for this, to replace the atari-specific one.

Enable CONFIG_HAVE_ARCH_NVRAM_OPS for Macs.

Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/m68k/kernel/setup_mm.c | 82 ++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 81 insertions(+), 1 deletion(-)

(limited to 'arch/m68k/kernel')

diff --git a/arch/m68k/kernel/setup_mm.c b/arch/m68k/kernel/setup_mm.c
index ad0195cbe042..528484feff80 100644
--- a/arch/m68k/kernel/setup_mm.c
+++ b/arch/m68k/kernel/setup_mm.c
@@ -24,6 +24,7 @@
 #include <linux/proc_fs.h>
 #include <linux/seq_file.h>
 #include <linux/module.h>
+#include <linux/nvram.h>
 #include <linux/initrd.h>
 
 #include <asm/bootinfo.h>
@@ -37,13 +38,14 @@
 #ifdef CONFIG_AMIGA
 #include <asm/amigahw.h>
 #endif
-#ifdef CONFIG_ATARI
 #include <asm/atarihw.h>
+#ifdef CONFIG_ATARI
 #include <asm/atari_stram.h>
 #endif
 #ifdef CONFIG_SUN3X
 #include <asm/dvma.h>
 #endif
+#include <asm/macintosh.h>
 #include <asm/natfeat.h>
 
 #if !FPSTATESIZE || !NR_IRQS
@@ -547,3 +549,81 @@ static int __init adb_probe_sync_enable (char *str) {
 
 __setup("adb_sync", adb_probe_sync_enable);
 #endif /* CONFIG_ADB */
+
+#if IS_ENABLED(CONFIG_NVRAM)
+#ifdef CONFIG_MAC
+static unsigned char m68k_nvram_read_byte(int addr)
+{
+	if (MACH_IS_MAC)
+		return mac_pram_read_byte(addr);
+	return 0xff;
+}
+
+static void m68k_nvram_write_byte(unsigned char val, int addr)
+{
+	if (MACH_IS_MAC)
+		mac_pram_write_byte(val, addr);
+}
+#endif /* CONFIG_MAC */
+
+#ifdef CONFIG_ATARI
+static ssize_t m68k_nvram_read(char *buf, size_t count, loff_t *ppos)
+{
+	if (MACH_IS_ATARI)
+		return atari_nvram_read(buf, count, ppos);
+	else if (MACH_IS_MAC)
+		return nvram_read_bytes(buf, count, ppos);
+	return -EINVAL;
+}
+
+static ssize_t m68k_nvram_write(char *buf, size_t count, loff_t *ppos)
+{
+	if (MACH_IS_ATARI)
+		return atari_nvram_write(buf, count, ppos);
+	else if (MACH_IS_MAC)
+		return nvram_write_bytes(buf, count, ppos);
+	return -EINVAL;
+}
+
+static long m68k_nvram_set_checksum(void)
+{
+	if (MACH_IS_ATARI)
+		return atari_nvram_set_checksum();
+	return -EINVAL;
+}
+
+static long m68k_nvram_initialize(void)
+{
+	if (MACH_IS_ATARI)
+		return atari_nvram_initialize();
+	return -EINVAL;
+}
+#endif /* CONFIG_ATARI */
+
+static ssize_t m68k_nvram_get_size(void)
+{
+	if (MACH_IS_ATARI)
+		return atari_nvram_get_size();
+	else if (MACH_IS_MAC)
+		return mac_pram_get_size();
+	return -ENODEV;
+}
+
+/* Atari device drivers call .read (to get checksum validation) whereas
+ * Mac and PowerMac device drivers just use .read_byte.
+ */
+const struct nvram_ops arch_nvram_ops = {
+#ifdef CONFIG_MAC
+	.read_byte      = m68k_nvram_read_byte,
+	.write_byte     = m68k_nvram_write_byte,
+#endif
+#ifdef CONFIG_ATARI
+	.read           = m68k_nvram_read,
+	.write          = m68k_nvram_write,
+	.set_checksum   = m68k_nvram_set_checksum,
+	.initialize     = m68k_nvram_initialize,
+#endif
+	.get_size       = m68k_nvram_get_size,
+};
+EXPORT_SYMBOL(arch_nvram_ops);
+#endif /* CONFIG_NVRAM */
-- 
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