[POWERPC] Start arch/powerpc/boot code reorganization

This abstracts the operations used in the bootwrapper, and defines
the operations needed for the bootwrapper to run on an OF platform.

The operations have been divided up into platform ops (platform_ops),
firmware ops (fw_ops), device tree ops (dt_ops), and console ops
(console_ops).

The proper operations will be hooked up at runtime to provide the
functionality that you need.

Signed-off-by: Mark A. Greer <mgreer@mvista.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 129 insertions, 121 deletions

diff --git a/arch/powerpc/boot/main.c b/arch/powerpc/boot/main.c
index b66634c..d719bb9 100644
--- a/arch/powerpc/boot/main.c
+++ b/arch/powerpc/boot/main.c
@@ -14,17 +14,12 @@
 #include "page.h"
 #include "string.h"
 #include "stdio.h"
-#include "prom.h"
 #include "zlib.h"
+#include "ops.h"
+#include "flatdevtree.h"
 
 extern void flush_cache(void *, unsigned long);
 
-
-/* Value picked to match that used by yaboot */
-#define PROG_START	0x01400000	/* only used on 64-bit systems */
-#define RAM_END		(512<<20)	/* Fixme: use OF */
-#define	ONE_MB		0x100000
-
 extern char _start[];
 extern char __bss_start[];
 extern char _end[];
@@ -33,14 +28,6 @@ extern char _vmlinux_end[];
 extern char _initrd_start[];
 extern char _initrd_end[];
 
-/* A buffer that may be edited by tools operating on a zImage binary so as to
- * edit the command line passed to vmlinux (by setting /chosen/bootargs).
- * The buffer is put in it's own section so that tools may locate it easier.
- */
-static char builtin_cmdline[512]
-	__attribute__((section("__builtin_cmdline")));
-
-
 struct addr_range {
 	unsigned long addr;
 	unsigned long size;
@@ -51,21 +38,16 @@ static struct addr_range vmlinuz;
 static struct addr_range initrd;
 
 static unsigned long elfoffset;
+static int is_64bit;
 
-static char scratch[46912];	/* scratch space for gunzip, from zlib_inflate_workspacesize() */
+/* scratch space for gunzip; 46912 is from zlib_inflate_workspacesize() */
+static char scratch[46912];
 static char elfheader[256];
 
-
-typedef void (*kernel_entry_t)( unsigned long,
-                                unsigned long,
-                                void *,
-				void *);
-
+typedef void (*kernel_entry_t)(unsigned long, unsigned long, void *);
 
 #undef DEBUG
 
-static unsigned long claim_base;
-
 #define HEAD_CRC	2
 #define EXTRA_FIELD	4
 #define ORIG_NAME	8
@@ -123,24 +105,6 @@ static void gunzip(void *dst, int dstlen, unsigned char *src, int *lenp)
 	zlib_inflateEnd(&s);
 }
 
-static unsigned long try_claim(unsigned long size)
-{
-	unsigned long addr = 0;
-
-	for(; claim_base < RAM_END; claim_base += ONE_MB) {
-#ifdef DEBUG
-		printf("    trying: 0x%08lx\n\r", claim_base);
-#endif
-		addr = (unsigned long)claim(claim_base, size, 0);
-		if ((void *)addr != (void *)-1)
-			break;
-	}
-	if (addr == 0)
-		return 0;
-	claim_base = PAGE_ALIGN(claim_base + size);
-	return addr;
-}
-
 static int is_elf64(void *hdr)
 {
 	Elf64_Ehdr *elf64 = hdr;
@@ -169,16 +133,7 @@ static int is_elf64(void *hdr)
 	vmlinux.size = (unsigned long)elf64ph->p_filesz + elfoffset;
 	vmlinux.memsize = (unsigned long)elf64ph->p_memsz + elfoffset;
 
-#if defined(PROG_START)
-	/*
-	 * Maintain a "magic" minimum address. This keeps some older
-	 * firmware platforms running.
-	 */
-
-	if (claim_base < PROG_START)
-		claim_base = PROG_START;
-#endif
-
+	is_64bit = 1;
 	return 1;
 }
 
@@ -212,47 +167,9 @@ static int is_elf32(void *hdr)
 	return 1;
 }
 
-void export_cmdline(void* chosen_handle)
-{
-        int len;
-        char cmdline[2] = { 0, 0 };
-
-	if (builtin_cmdline[0] == 0)
-		return;
-
-        len = getprop(chosen_handle, "bootargs", cmdline, sizeof(cmdline));
-        if (len > 0 && cmdline[0] != 0)
-		return;
-
-	setprop(chosen_handle, "bootargs", builtin_cmdline,
-		strlen(builtin_cmdline) + 1);
-}
-
-
-void start(unsigned long a1, unsigned long a2, void *promptr, void *sp)
+static void prep_kernel(unsigned long *a1, unsigned long *a2)
 {
 	int len;
-	kernel_entry_t kernel_entry;
-
-	memset(__bss_start, 0, _end - __bss_start);
-
-	prom = (int (*)(void *)) promptr;
-	chosen_handle = finddevice("/chosen");
-	if (chosen_handle == (void *) -1)
-		exit();
-	if (getprop(chosen_handle, "stdout", &stdout, sizeof(stdout)) != 4)
-		exit();
-
-	printf("\n\rzImage starting: loaded at 0x%p (sp: 0x%p)\n\r", _start, sp);
-
-	/*
-	 * The first available claim_base must be above the end of the
-	 * the loaded kernel wrapper file (_start to _end includes the
-	 * initrd image if it is present) and rounded up to a nice
-	 * 1 MB boundary for good measure.
-	 */
-
-	claim_base = _ALIGN_UP((unsigned long)_end, ONE_MB);
 
 	vmlinuz.addr = (unsigned long)_vmlinux_start;
 	vmlinuz.size = (unsigned long)(_vmlinux_end - _vmlinux_start);
@@ -263,43 +180,51 @@ void start(unsigned long a1, unsigned long a2, void *promptr, void *sp)
 		gunzip(elfheader, sizeof(elfheader),
 				(unsigned char *)vmlinuz.addr, &len);
 	} else
-		memcpy(elfheader, (const void *)vmlinuz.addr, sizeof(elfheader));
+		memcpy(elfheader, (const void *)vmlinuz.addr,
+		       sizeof(elfheader));
 
 	if (!is_elf64(elfheader) && !is_elf32(elfheader)) {
 		printf("Error: not a valid PPC32 or PPC64 ELF file!\n\r");
 		exit();
 	}
+	if (platform_ops.image_hdr)
+		platform_ops.image_hdr(elfheader);
 
-	/* We need to claim the memsize plus the file offset since gzip
+	/* We need to alloc the memsize plus the file offset since gzip
 	 * will expand the header (file offset), then the kernel, then
 	 * possible rubbish we don't care about. But the kernel bss must
 	 * be claimed (it will be zero'd by the kernel itself)
 	 */
 	printf("Allocating 0x%lx bytes for kernel ...\n\r", vmlinux.memsize);
-	vmlinux.addr = try_claim(vmlinux.memsize);
+	vmlinux.addr = (unsigned long)malloc(vmlinux.memsize);
 	if (vmlinux.addr == 0) {
 		printf("Can't allocate memory for kernel image !\n\r");
 		exit();
 	}
 
 	/*
-	 * Now we try to claim memory for the initrd (and copy it there)
+	 * Now we try to alloc memory for the initrd (and copy it there)
 	 */
 	initrd.size = (unsigned long)(_initrd_end - _initrd_start);
 	initrd.memsize = initrd.size;
 	if ( initrd.size > 0 ) {
-		printf("Allocating 0x%lx bytes for initrd ...\n\r", initrd.size);
-		initrd.addr = try_claim(initrd.size);
+		printf("Allocating 0x%lx bytes for initrd ...\n\r",
+		       initrd.size);
+		initrd.addr = (unsigned long)malloc((u32)initrd.size);
 		if (initrd.addr == 0) {
-			printf("Can't allocate memory for initial ramdisk !\n\r");
+			printf("Can't allocate memory for initial "
+					"ramdisk !\n\r");
 			exit();
 		}
-		a1 = initrd.addr;
-		a2 = initrd.size;
-		printf("initial ramdisk moving 0x%lx <- 0x%lx (0x%lx bytes)\n\r",
-		       initrd.addr, (unsigned long)_initrd_start, initrd.size);
-		memmove((void *)initrd.addr, (void *)_initrd_start, initrd.size);
-		printf("initrd head: 0x%lx\n\r", *((unsigned long *)initrd.addr));
+		*a1 = initrd.addr;
+		*a2 = initrd.size;
+		printf("initial ramdisk moving 0x%lx <- 0x%lx "
+			"(0x%lx bytes)\n\r", initrd.addr,
+			(unsigned long)_initrd_start, initrd.size);
+		memmove((void *)initrd.addr, (void *)_initrd_start,
+			initrd.size);
+		printf("initrd head: 0x%lx\n\r",
+				*((unsigned long *)initrd.addr));
 	}
 
 	/* Eventually gunzip the kernel */
@@ -311,11 +236,10 @@ void start(unsigned long a1, unsigned long a2, void *promptr, void *sp)
 			(unsigned char *)vmlinuz.addr, &len);
 		printf("done 0x%lx bytes\n\r", len);
 	} else {
-		memmove((void *)vmlinux.addr,(void *)vmlinuz.addr,vmlinuz.size);
+		memmove((void *)vmlinux.addr,(void *)vmlinuz.addr,
+			vmlinuz.size);
 	}
 
-	export_cmdline(chosen_handle);
-
 	/* Skip over the ELF header */
 #ifdef DEBUG
 	printf("... skipping 0x%lx bytes of ELF header\n\r",
@@ -324,23 +248,107 @@ void start(unsigned long a1, unsigned long a2, void *promptr, void *sp)
 	vmlinux.addr += elfoffset;
 
 	flush_cache((void *)vmlinux.addr, vmlinux.size);
+}
 
-	kernel_entry = (kernel_entry_t)vmlinux.addr;
-#ifdef DEBUG
-	printf( "kernel:\n\r"
-		"        entry addr = 0x%lx\n\r"
-		"        a1         = 0x%lx,\n\r"
-		"        a2         = 0x%lx,\n\r"
-		"        prom       = 0x%lx,\n\r"
-		"        bi_recs    = 0x%lx,\n\r",
-		(unsigned long)kernel_entry, a1, a2,
-		(unsigned long)prom, NULL);
-#endif
+void __attribute__ ((weak)) ft_init(void *dt_blob)
+{
+}
 
-	kernel_entry(a1, a2, prom, NULL);
+/* A buffer that may be edited by tools operating on a zImage binary so as to
+ * edit the command line passed to vmlinux (by setting /chosen/bootargs).
+ * The buffer is put in it's own section so that tools may locate it easier.
+ */
+static char builtin_cmdline[COMMAND_LINE_SIZE]
+	__attribute__((__section__("__builtin_cmdline")));
 
-	printf("Error: Linux kernel returned to zImage bootloader!\n\r");
+static void get_cmdline(char *buf, int size)
+{
+	void *devp;
+	int len = strlen(builtin_cmdline);
 
-	exit();
+	buf[0] = '\0';
+
+	if (len > 0) { /* builtin_cmdline overrides dt's /chosen/bootargs */
+		len = min(len, size-1);
+		strncpy(buf, builtin_cmdline, len);
+		buf[len] = '\0';
+	}
+	else if ((devp = finddevice("/chosen")))
+		getprop(devp, "bootargs", buf, size);
+}
+
+static void set_cmdline(char *buf)
+{
+	void *devp;
+
+	if ((devp = finddevice("/chosen")))
+		setprop(devp, "bootargs", buf, strlen(buf) + 1);
 }
 
+/* Section where ft can be tacked on after zImage is built */
+union blobspace {
+	struct boot_param_header hdr;
+	char space[8*1024];
+} dt_blob __attribute__((__section__("__builtin_ft")));
+
+struct platform_ops platform_ops;
+struct dt_ops dt_ops;
+struct console_ops console_ops;
+
+void start(unsigned long a1, unsigned long a2, void *promptr, void *sp)
+{
+	int have_dt = 0;
+	kernel_entry_t kentry;
+	char cmdline[COMMAND_LINE_SIZE];
+
+	memset(__bss_start, 0, _end - __bss_start);
+	memset(&platform_ops, 0, sizeof(platform_ops));
+	memset(&dt_ops, 0, sizeof(dt_ops));
+	memset(&console_ops, 0, sizeof(console_ops));
+
+	/* Override the dt_ops and device tree if there was an flat dev
+	 * tree attached to the zImage.
+	 */
+	if (dt_blob.hdr.magic == OF_DT_HEADER) {
+		have_dt = 1;
+		ft_init(&dt_blob);
+	}
+
+	if (platform_init(promptr))
+		exit();
+	if (console_ops.open && (console_ops.open() < 0))
+		exit();
+	if (platform_ops.fixups)
+		platform_ops.fixups();
+
+	printf("\n\rzImage starting: loaded at 0x%p (sp: 0x%p)\n\r",
+	       _start, sp);
+
+	prep_kernel(&a1, &a2);
+
+	/* If cmdline came from zimage wrapper or if we can edit the one
+	 * in the dt, print it out and edit it, if possible.
+	 */
+	if ((strlen(builtin_cmdline) > 0) || console_ops.edit_cmdline) {
+		get_cmdline(cmdline, COMMAND_LINE_SIZE);
+		printf("\n\rLinux/PowerPC load: %s", cmdline);
+		if (console_ops.edit_cmdline)
+			console_ops.edit_cmdline(cmdline, COMMAND_LINE_SIZE);
+		printf("\n\r");
+		set_cmdline(cmdline);
+	}
+
+	if (console_ops.close)
+		console_ops.close();
+
+	kentry = (kernel_entry_t) vmlinux.addr;
+	if (have_dt)
+		kentry(dt_ops.ft_addr(), 0, NULL);
+	else
+		/* XXX initrd addr/size should be passed in properties */
+		kentry(a1, a2, promptr);
+
+	/* console closed so printf below may not work */
+	printf("Error: Linux kernel returned to zImage boot wrapper!\n\r");
+	exit();
+}