brcm47xx: add support for the kernel 4.19

One patch that wasn't ported due to a lot of conflict is:
901-Revert-bcma-switch-GPIO-portions-to-use-GPIOLIB_IRQC.patch

Hopefully a correct/real fix will get developed before we switch
brcm47xx to the 4.14.

This IS NOT ready for switching/trying/using 4.19 yet due to some DMA
regression affecting bgmac:
[    0.945472] bgmac_bcma bcma0:2: Found PHY addr: 25
[    0.954565] libphy: bcma_mdio mii bus: probed
[    0.959486] ------------[ cut here ]------------
[    0.964387] WARNING: CPU: 0 PID: 1 at ./include/linux/dma-mapping.h:516 bgmac_enet_probe+0x1b4/0x5c4
[    0.973751] Modules linked in:
[    0.976913] CPU: 0 PID: 1 Comm: swapper Not tainted 4.19.9 #0
[    0.982750] Stack : 804a0000 804597c4 00000000 00000000 80458fd8 8381bc2c 838282d4 80481a47
[    0.991367]         8042e3ec 00000001 804d38f0 00000204 83980000 00000065 8381bbe0 6f55b24f
[    0.999975]         00000000 00000000 80520000 00002018 00000000 00000075 00000007 00000000
[    1.008583]         00000000 80480000 000ee811 00000000 00000000 00000000 80432c00 80248db8
[    1.017196]         00000009 00000204 83980000 803ad7b0 00000000 801feeec 00000000 804d0000
[    1.025804]         ...
[    1.028325] Call Trace:
[    1.030875] [<8000aef8>] show_stack+0x58/0x100
[    1.035513] [<8001f8b4>] __warn+0xe4/0x118
[    1.039708] [<8001f9a4>] warn_slowpath_null+0x48/0x64
[    1.044935] [<80248db8>] bgmac_enet_probe+0x1b4/0x5c4
[    1.050101] [<802498e0>] bgmac_probe+0x558/0x590
[    1.054906] [<80252fd0>] bcma_device_probe+0x38/0x70
[    1.060017] [<8020e1e8>] really_probe+0x170/0x2e8
[    1.064891] [<8020e714>] __driver_attach+0xa4/0xec
[    1.069784] [<8020c1e0>] bus_for_each_dev+0x58/0xb0
[    1.074833] [<8020d590>] bus_add_driver+0xf8/0x218
[    1.079731] [<8020ef24>] driver_register+0xcc/0x11c
[    1.084804] [<804b54cc>] bgmac_init+0x1c/0x44
[    1.089258] [<8000121c>] do_one_initcall+0x7c/0x1a0
[    1.094343] [<804a1d34>] kernel_init_freeable+0x150/0x218
[    1.099886] [<803a082c>] kernel_init+0x10/0x104
[    1.104583] [<80005878>] ret_from_kernel_thread+0x14/0x1c
[    1.110107] ---[ end trace f441c0d873d1fb5b ]---
[    1.114914] bgmac_bcma bcma0:2: Allocation of TX ring 0x200 failed
[    1.121215] bgmac_bcma bcma0:2: Unable to alloc memory for DMA
[    1.127626] bgmac_bcma: probe of bcma0:2 failed with error -12
[    1.133838] bgmac_bcma: Broadcom 47xx GBit MAC driver loaded

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

1 files changed, 74 insertions, 0 deletions

diff --git a/target/linux/brcm47xx/patches-4.19/310-no_highpage.patch b/target/linux/brcm47xx/patches-4.19/310-no_highpage.patch
new file mode 100644
index 0000000000..09bfc64552
--- /dev/null
+++ b/target/linux/brcm47xx/patches-4.19/310-no_highpage.patch
@@ -0,0 +1,74 @@
+From: Jeff Hansen <jhansen@cardaccess-inc.com>
+Subject: [PATCH] no highpage
+
+On ASUS WL-500gP there are many unexpected "Segmentation fault"s that
+seem to be caused by a kernel. They can be avoided by:
+1) Disabling highpage
+2) Using flush_cache_mm in flush_cache_dup_mm
+
+For details see OpenWrt ticket #2035 https://dev.openwrt.org/ticket/2035
+---
+--- a/arch/mips/include/asm/page.h
++++ b/arch/mips/include/asm/page.h
+@@ -71,6 +71,7 @@ static inline unsigned int page_size_ftl
+ #endif /* CONFIG_MIPS_HUGE_TLB_SUPPORT */
+ 
+ #include <linux/pfn.h>
++#include <asm/cpu-features.h>
+ 
+ extern void build_clear_page(void);
+ extern void build_copy_page(void);
+@@ -110,11 +111,16 @@ static inline void clear_user_page(void
+ 		flush_data_cache_page((unsigned long)addr);
+ }
+ 
+-struct vm_area_struct;
+-extern void copy_user_highpage(struct page *to, struct page *from,
+-	unsigned long vaddr, struct vm_area_struct *vma);
++static inline void copy_user_page(void *vto, void *vfrom, unsigned long vaddr,
++	struct page *to)
++{
++	extern void (*flush_data_cache_page)(unsigned long addr);
+ 
+-#define __HAVE_ARCH_COPY_USER_HIGHPAGE
++	copy_page(vto, vfrom);
++	if (!cpu_has_ic_fills_f_dc ||
++	    pages_do_alias((unsigned long)vto, vaddr & PAGE_MASK))
++		flush_data_cache_page((unsigned long)vto);
++}
+ 
+ /*
+  * These are used to make use of C type-checking..
+--- a/arch/mips/mm/init.c
++++ b/arch/mips/mm/init.c
+@@ -162,30 +162,6 @@ void kunmap_coherent(void)
+ 	preempt_enable();
+ }
+ 
+-void copy_user_highpage(struct page *to, struct page *from,
+-	unsigned long vaddr, struct vm_area_struct *vma)
+-{
+-	void *vfrom, *vto;
+-
+-	vto = kmap_atomic(to);
+-	if (cpu_has_dc_aliases && cpu_use_kmap_coherent &&
+-	    page_mapcount(from) && !Page_dcache_dirty(from)) {
+-		vfrom = kmap_coherent(from, vaddr);
+-		copy_page(vto, vfrom);
+-		kunmap_coherent();
+-	} else {
+-		vfrom = kmap_atomic(from);
+-		copy_page(vto, vfrom);
+-		kunmap_atomic(vfrom);
+-	}
+-	if ((!cpu_has_ic_fills_f_dc) ||
+-	    pages_do_alias((unsigned long)vto, vaddr & PAGE_MASK))
+-		flush_data_cache_page((unsigned long)vto);
+-	kunmap_atomic(vto);
+-	/* Make sure this page is cleared on other CPU's too before using it */
+-	smp_wmb();
+-}
+-
+ void copy_to_user_page(struct vm_area_struct *vma,
+ 	struct page *page, unsigned long vaddr, void *dst, const void *src,
+ 	unsigned long len)