1 files changed, 173 insertions, 0 deletions
diff --git a/arch/ppc/kernel/prep_nvram.c b/arch/ppc/kernel/prep_nvram.c
new file mode 100644
index 000000000..e69563c8a
--- /dev/null
+++ b/arch/ppc/kernel/prep_nvram.c
@@ -0,0 +1,173 @@
+/*
+ *  linux/arch/ppc/kernel/prep_nvram.c
+ *
+ *  Copyright (C) 1998  Corey Minyard
+ *
+ */
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/malloc.h>
+#include <linux/ioport.h>
+
+#include <asm/segment.h>
+#include <asm/io.h>
+#include <asm/processor.h>
+#include <asm/machdep.h>
+#include <asm/prep_nvram.h>
+
+/*
+ * Allow for a maximum of 32K of PReP NvRAM data
+ */
+#define MAX_PREP_NVRAM 0x8000
+static char nvramData[MAX_PREP_NVRAM];
+static NVRAM_MAP *nvram=(NVRAM_MAP *)&nvramData[0];
+
+#define PREP_NVRAM_AS0	0x74
+#define PREP_NVRAM_AS1	0x75
+#define PREP_NVRAM_DATA	0x77
+
+unsigned char *rs_pcNvRAM;
+
+unsigned char prep_nvram_read_val(int addr)
+{
+	outb(addr, PREP_NVRAM_AS0);
+	outb(addr>>8, PREP_NVRAM_AS1);
+	return inb(PREP_NVRAM_DATA);
+}
+  
+void prep_nvram_write_val(int           addr,
+			  unsigned char val)
+{
+	outb(addr, PREP_NVRAM_AS0);
+	outb(addr>>8, PREP_NVRAM_AS1);
+   	outb(val, PREP_NVRAM_DATA);
+}
+  
+/*
+ * Most Radstone boards have NvRAM memory mapped at offset 8M in ISA space
+ */
+unsigned char rs_nvram_read_val(int addr)
+{
+	return rs_pcNvRAM[addr];
+}
+  
+void rs_nvram_write_val(int addr,
+			unsigned char val)
+{
+	rs_pcNvRAM[addr]=val;
+}
+  
+__initfunc(void init_prep_nvram(void))
+{
+	unsigned char *nvp;
+	int  i;
+	int  nvramSize;
+
+	/*
+	 * I'm making the assumption that 32k will always cover the
+	 * nvramsize.  If this isn't the case please let me know and we can
+	 * map the header, then get the size from the header, then map
+	 * the whole size. -- Cort
+	 */
+	if ( _prep_type == _PREP_Radstone )
+		rs_pcNvRAM = (unsigned char *)ioremap(_ISA_MEM_BASE+0x00800000,
+						      32<<10);
+	request_region(PREP_NVRAM_AS0, 0x8, "PReP NVRAM");
+	/*
+	 * The following could fail if the NvRAM were corrupt but
+	 * we expect the boot firmware to have checked its checksum
+	 * before boot
+	 */
+	nvp = (char *) &nvram->Header;
+	for (i=0; i<sizeof(HEADER); i++)
+	{
+		*nvp = ppc_md.nvram_read_val(i);
+		nvp++;
+	}
+	
+	/*
+	 * The PReP NvRAM may be any size so read in the header to
+	 * determine how much we must read in order to get the complete
+	 * GE area
+	 */
+	nvramSize=(int)nvram->Header.GEAddress+nvram->Header.GELength;
+	if(nvramSize>MAX_PREP_NVRAM)
+	{
+		/*
+		 * NvRAM is too large
+		 */
+		nvram->Header.GELength=0;
+		return;
+	}
+
+	/*
+	 * Read the remainder of the PReP NvRAM
+	 */
+	nvp = (char *) &nvram->GEArea[0];
+	for (i=sizeof(HEADER); i<nvramSize; i++)
+	{
+		*nvp = ppc_md.nvram_read_val(i);
+		nvp++;
+	}
+}
+
+__prep
+char *prep_nvram_get_var(const char *name)
+{
+	char *cp;
+	int  namelen;
+
+	namelen = strlen(name);
+	cp = prep_nvram_first_var();
+	while (cp != NULL) {
+		if ((strncmp(name, cp, namelen) == 0)
+		    && (cp[namelen] == '='))
+		{
+			return cp+namelen+1;
+		}
+		cp = prep_nvram_next_var(cp);
+	}
+
+	return NULL;
+}
+
+__prep
+char *prep_nvram_first_var(void)
+{
+        if (nvram->Header.GELength == 0) {
+		return NULL;
+	} else {
+		return (((char *)nvram)
+			+ ((unsigned int) nvram->Header.GEAddress));
+	}
+}
+
+__prep
+char *prep_nvram_next_var(char *name)
+{
+	char *cp;
+
+
+	cp = name;
+	while (((cp - ((char *) nvram->GEArea)) < nvram->Header.GELength)
+	       && (*cp != '\0'))
+	{
+		cp++;
+	}
+
+	/* Skip over any null characters. */
+	while (((cp - ((char *) nvram->GEArea)) < nvram->Header.GELength)
+	       && (*cp == '\0'))
+	{
+		cp++;
+	}
+
+	if ((cp - ((char *) nvram->GEArea)) < nvram->Header.GELength) {
+		return cp;
+	} else {
+		return NULL;
+	}
+}
+
+
+