fix modules_install via NFS

Rafael reported:

I get the following error from 'make modules_install' on my test boxes:

  HOSTCC  firmware/ihex2fw
/home/rafael/src/linux-2.6/firmware/ihex2fw.c:268: fatal error: opening dependency file firmware/.ihex2fw.d: Read-only file system
compilation terminated.
make[3]: *** [firmware/ihex2fw] Error 1
make[2]: *** [_modinst_post] Error 2
make[1]: *** [sub-make] Error 2
make: *** [all] Error 2

where the configuration is that the kernel is compiled on a build box
with 'make O=<destdir> -j5' and then <destdir> is mounted over NFS read-only by
each test box (full path to this directory is the same on the build box and on
the test boxes).  Then, I cd into <destdir>, run 'make modules_install' and get
the error above.

The issue turns out to be that we when we install firmware pick
up the list of firmware blobs from firmware/Makefile.
And this triggers the Makefile rules to update ihex2fw.

There were two solutions for this issue:
1) Move the list of firmware blobs to a separate file
2) Avoid ihex2fw rebuild by moving it to scripts

As I seriously beleive that the list of firmware blobs should be
done in a fundamental different way solution 2) was selected.

Reported-and-tested-by: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: David Woodhouse <dwmw2@infradead.org>

3 files changed, 4 insertions, 275 deletions

diff --git a/firmware/.gitignore b/firmware/.gitignore
index d9c69017bc9a..f89a21fffbf1 100644
--- a/firmware/.gitignore
+++ b/firmware/.gitignore
@@ -3,4 +3,3 @@
 *.bin
 *.csp
 *.dsp
-ihex2fw
diff --git a/firmware/Makefile b/firmware/Makefile
index d872b7942a30..55d3082ea13e 100644
--- a/firmware/Makefile
+++ b/firmware/Makefile
@@ -99,10 +99,10 @@ quiet_cmd_ihex  = IHEX    $@
       cmd_ihex  = $(OBJCOPY) -Iihex -Obinary $< $@
 
 quiet_cmd_ihex2fw  = IHEX2FW $@
-      cmd_ihex2fw  = $(objtree)/$(obj)/ihex2fw $< $@
+      cmd_ihex2fw  = $(objtree)/scripts/ihex2fw $< $@
 
 quiet_cmd_h16tofw  = H16TOFW $@
-      cmd_h16tofw  = $(objtree)/$(obj)/ihex2fw -w $< $@
+      cmd_h16tofw  = $(objtree)/scripts/ihex2fw -w $< $@
 
 quiet_cmd_fwbin = MK_FW   $@
       cmd_fwbin = FWNAME="$(patsubst firmware/%.gen.S,%,$@)";		     \
@@ -165,11 +165,11 @@ $(obj)/%: $(obj)/%.ihex | $(objtree)/$(obj)/$$(dir %)
 # is actually meaningful, because the firmware has to be loaded in a certain
 # order rather than as a single binary blob. Thus, we convert them into our
 # more compact binary representation of ihex records (<linux/ihex.h>)
-$(obj)/%.fw: $(obj)/%.HEX $(obj)/ihex2fw | $(objtree)/$(obj)/$$(dir %)
+$(obj)/%.fw: $(obj)/%.HEX  | $(objtree)/$(obj)/$$(dir %)
 	$(call cmd,ihex2fw)
 
 # .H16 is our own modified form of Intel HEX, with 16-bit length for records.
-$(obj)/%.fw: $(obj)/%.H16 $(obj)/ihex2fw | $(objtree)/$(obj)/$$(dir %)
+$(obj)/%.fw: $(obj)/%.H16 | $(objtree)/$(obj)/$$(dir %)
 	$(call cmd,h16tofw)
 
 $(firmware-dirs):
@@ -186,5 +186,3 @@ targets := $(fw-shipped-) $(patsubst $(obj)/%,%, \
 # Without this, built-in.o won't be created when it's empty, and the
 # final vmlinux link will fail.
 obj-n := dummy
-
-hostprogs-y := ihex2fw
diff --git a/firmware/ihex2fw.c b/firmware/ihex2fw.c
deleted file mode 100644
index 8f7fdaa9e010..000000000000
--- a/firmware/ihex2fw.c
+++ /dev/null
@@ -1,268 +0,0 @@
-/*
- * Parser/loader for IHEX formatted data.
- *
- * Copyright © 2008 David Woodhouse <dwmw2@infradead.org>
- * Copyright © 2005 Jan Harkes <jaharkes@cs.cmu.edu>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- */
-
-#include <stdint.h>
-#include <arpa/inet.h>
-#include <stdio.h>
-#include <errno.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <sys/mman.h>
-#include <fcntl.h>
-#include <string.h>
-#include <unistd.h>
-#include <stdlib.h>
-#define _GNU_SOURCE
-#include <getopt.h>
-
-
-struct ihex_binrec {
-	struct ihex_binrec *next; /* not part of the real data structure */
-        uint32_t addr;
-        uint16_t len;
-        uint8_t data[];
-};
-
-/**
- * nybble/hex are little helpers to parse hexadecimal numbers to a byte value
- **/
-static uint8_t nybble(const uint8_t n)
-{
-       if      (n >= '0' && n <= '9') return n - '0';
-       else if (n >= 'A' && n <= 'F') return n - ('A' - 10);
-       else if (n >= 'a' && n <= 'f') return n - ('a' - 10);
-       return 0;
-}
-
-static uint8_t hex(const uint8_t *data, uint8_t *crc)
-{
-       uint8_t val = (nybble(data[0]) << 4) | nybble(data[1]);
-       *crc += val;
-       return val;
-}
-
-static int process_ihex(uint8_t *data, ssize_t size);
-static void file_record(struct ihex_binrec *record);
-static int output_records(int outfd);
-
-static int sort_records = 0;
-static int wide_records = 0;
-
-int usage(void)
-{
-	fprintf(stderr, "ihex2fw: Convert ihex files into binary "
-		"representation for use by Linux kernel\n");
-	fprintf(stderr, "usage: ihex2fw [<options>] <src.HEX> <dst.fw>\n");
-	fprintf(stderr, "       -w: wide records (16-bit length)\n");
-	fprintf(stderr, "       -s: sort records by address\n");
-	return 1;
-}
-
-int main(int argc, char **argv)
-{
-	int infd, outfd;
-	struct stat st;
-	uint8_t *data;
-	int opt;
-
-	while ((opt = getopt(argc, argv, "ws")) != -1) {
-		switch (opt) {
-		case 'w':
-			wide_records = 1;
-			break;
-		case 's':
-			sort_records = 1;
-			break;
-		default:
-			return usage();
-		}
-	}
-
-	if (optind + 2 != argc)
-		return usage();
-
-	if (!strcmp(argv[optind], "-"))
-	    infd = 0;
-	else
-		infd = open(argv[optind], O_RDONLY);
-	if (infd == -1) {
-		fprintf(stderr, "Failed to open source file: %s",
-			strerror(errno));
-		return usage();
-	}
-	if (fstat(infd, &st)) {
-		perror("stat");
-		return 1;
-	}
-	data = mmap(NULL, st.st_size, PROT_READ, MAP_SHARED, infd, 0);
-	if (data == MAP_FAILED) {
-		perror("mmap");
-		return 1;
-	}
-
-	if (!strcmp(argv[optind+1], "-"))
-	    outfd = 1;
-	else
-		outfd = open(argv[optind+1], O_TRUNC|O_CREAT|O_WRONLY, 0644);
-	if (outfd == -1) {
-		fprintf(stderr, "Failed to open destination file: %s",
-			strerror(errno));
-		return usage();
-	}
-	if (process_ihex(data, st.st_size))
-		return 1;
-
-	output_records(outfd);
-	return 0;
-}
-
-static int process_ihex(uint8_t *data, ssize_t size)
-{
-	struct ihex_binrec *record;
-	uint32_t offset = 0;
-	uint8_t type, crc = 0, crcbyte = 0;
-	int i, j;
-	int line = 1;
-	int len;
-
-	i = 0;
-next_record:
-	/* search for the start of record character */
-	while (i < size) {
-		if (data[i] == '\n') line++;
-		if (data[i++] == ':') break;
-	}
-
-	/* Minimum record length would be about 10 characters */
-	if (i + 10 > size) {
-		fprintf(stderr, "Can't find valid record at line %d\n", line);
-		return -EINVAL;
-	}
-
-	len = hex(data + i, &crc); i += 2;
-	if (wide_records) {
-		len <<= 8;
-		len += hex(data + i, &crc); i += 2;
-	}
-	record = malloc((sizeof (*record) + len + 3) & ~3);
-	if (!record) {
-		fprintf(stderr, "out of memory for records\n");
-		return -ENOMEM;
-	}
-	memset(record, 0, (sizeof(*record) + len + 3) & ~3);
-	record->len = len;
-
-	/* now check if we have enough data to read everything */
-	if (i + 8 + (record->len * 2) > size) {
-		fprintf(stderr, "Not enough data to read complete record at line %d\n",
-			line);
-		return -EINVAL;
-	}
-
-	record->addr  = hex(data + i, &crc) << 8; i += 2;
-	record->addr |= hex(data + i, &crc); i += 2;
-	type = hex(data + i, &crc); i += 2;
-
-	for (j = 0; j < record->len; j++, i += 2)
-		record->data[j] = hex(data + i, &crc);
-
-	/* check CRC */
-	crcbyte = hex(data + i, &crc); i += 2;
-	if (crc != 0) {
-		fprintf(stderr, "CRC failure at line %d: got 0x%X, expected 0x%X\n",
-			line, crcbyte, (unsigned char)(crcbyte-crc));
-		return -EINVAL;
-	}
-
-	/* Done reading the record */
-	switch (type) {
-	case 0:
-		/* old style EOF record? */
-		if (!record->len)
-			break;
-
-		record->addr += offset;
-		file_record(record);
-		goto next_record;
-
-	case 1: /* End-Of-File Record */
-		if (record->addr || record->len) {
-			fprintf(stderr, "Bad EOF record (type 01) format at line %d",
-				line);
-			return -EINVAL;
-		}
-		break;
-
-	case 2: /* Extended Segment Address Record (HEX86) */
-	case 4: /* Extended Linear Address Record (HEX386) */
-		if (record->addr || record->len != 2) {
-			fprintf(stderr, "Bad HEX86/HEX386 record (type %02X) at line %d\n",
-				type, line);
-			return -EINVAL;
-		}
-
-		/* We shouldn't really be using the offset for HEX86 because
-		 * the wraparound case is specified quite differently. */
-		offset = record->data[0] << 8 | record->data[1];
-		offset <<= (type == 2 ? 4 : 16);
-		goto next_record;
-
-	case 3: /* Start Segment Address Record */
-	case 5: /* Start Linear Address Record */
-		if (record->addr || record->len != 4) {
-			fprintf(stderr, "Bad Start Address record (type %02X) at line %d\n",
-				type, line);
-			return -EINVAL;
-		}
-
-		/* These records contain the CS/IP or EIP where execution
-		 * starts. Don't really know what to do with them. */
-		goto next_record;
-
-	default:
-		fprintf(stderr, "Unknown record (type %02X)\n", type);
-		return -EINVAL;
-	}
-
-	return 0;
-}
-
-static struct ihex_binrec *records;
-
-static void file_record(struct ihex_binrec *record)
-{
-	struct ihex_binrec **p = &records;
-
-	while ((*p) && (!sort_records || (*p)->addr < record->addr))
-		p = &((*p)->next);
-
-	record->next = *p;
-	*p = record;
-}
-
-static int output_records(int outfd)
-{
-	unsigned char zeroes[6] = {0, 0, 0, 0, 0, 0};
-	struct ihex_binrec *p = records;
-
-	while (p) {
-		uint16_t writelen = (p->len + 9) & ~3;
-
-		p->addr = htonl(p->addr);
-		p->len = htons(p->len);
-		write(outfd, &p->addr, writelen);
-		p = p->next;
-	}
-	/* EOF record is zero length, since we don't bother to represent
-	   the type field in the binary version */
-	write(outfd, zeroes, 6);
-	return 0;
-}