bcm47xx: add support for kernel 5.4

Ethernet, switch, LEDs, buttons, USB, sysupgrade & LuCI were
successfully tested on BCM4706.

WARNING: Hack for BCM4710 adding BCM4710_PROTECTED_FILL_TLB() to the
local_r4k_flush_cache_sigtramp() could not be ported. That function has
been dropped in:
commit adcc81f148d7 ("MIPS: math-emu: Write-protect delay slot emulation pages")
commit 3315b6b336c8 ("MIPS: Delete unused flush_cache_sigtramp()")
it's unsure if that chipset will still work reliably.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>

1 files changed, 34 insertions, 0 deletions

diff --git a/target/linux/bcm47xx/patches-5.4/400-mtd-bcm47xxpart-get-nvram.patch b/target/linux/bcm47xx/patches-5.4/400-mtd-bcm47xxpart-get-nvram.patch
new file mode 100644
index 0000000000..17abe89d1d
--- /dev/null
+++ b/target/linux/bcm47xx/patches-5.4/400-mtd-bcm47xxpart-get-nvram.patch
@@ -0,0 +1,34 @@
+--- a/drivers/mtd/parsers/bcm47xxpart.c
++++ b/drivers/mtd/parsers/bcm47xxpart.c
+@@ -98,6 +98,7 @@ static int bcm47xxpart_parse(struct mtd_
+ 	int trx_num = 0; /* Number of found TRX partitions */
+ 	int possible_nvram_sizes[] = { 0x8000, 0xF000, 0x10000, };
+ 	int err;
++	bool found_nvram = false;
+ 
+ 	/*
+ 	 * Some really old flashes (like AT45DB*) had smaller erasesize-s, but
+@@ -279,12 +280,23 @@ static int bcm47xxpart_parse(struct mtd_
+ 		if (buf[0] == NVRAM_HEADER) {
+ 			bcm47xxpart_add_part(&parts[curr_part++], "nvram",
+ 					     master->size - blocksize, 0);
++			found_nvram = true;
+ 			break;
+ 		}
+ 	}
+ 
+ 	kfree(buf);
+ 
++	if (!found_nvram) {
++		pr_err("can not find a nvram partition reserve last block\n");
++		bcm47xxpart_add_part(&parts[curr_part++], "nvram_guess",
++				     master->size - blocksize * 2, MTD_WRITEABLE);
++		for (i = 0; i < curr_part; i++) {
++			if (parts[i].size + parts[i].offset == master->size)
++				parts[i].offset -= blocksize * 2;
++		}
++	}
++
+ 	/*
+ 	 * Assume that partitions end at the beginning of the one they are
+ 	 * followed by.