bcm27xx: import latest patches from the RPi foundation

bcm2708: boot tested on RPi B+ v1.2
bcm2709: boot tested on RPi 3B v1.2 and RPi 4B v1.1 4G
bcm2710: boot tested on RPi 3B v1.2
bcm2711: boot tested on RPi 4B v1.1 4G

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
(cherry-picked from commit f07e572f64)

1 files changed, 105 insertions, 0 deletions

diff --git a/target/linux/bcm27xx/patches-5.4/950-0626-arm64-mm-Fix-initialisation-of-DMA-zones-on-non-NUMA.patch b/target/linux/bcm27xx/patches-5.4/950-0626-arm64-mm-Fix-initialisation-of-DMA-zones-on-non-NUMA.patch
new file mode 100644
index 0000000000..0f4f09ee1c
--- /dev/null
+++ b/target/linux/bcm27xx/patches-5.4/950-0626-arm64-mm-Fix-initialisation-of-DMA-zones-on-non-NUMA.patch
@@ -0,0 +1,105 @@
+From cd2d09e995bc72711b48b5c271b72e3ea3e99cdf Mon Sep 17 00:00:00 2001
+From: Will Deacon <will@kernel.org>
+Date: Tue, 3 Dec 2019 12:10:13 +0000
+Subject: [PATCH] arm64: mm: Fix initialisation of DMA zones on
+ non-NUMA systems
+
+commit 93b90414c33f59b7960bc8d607da0ce83377e021 upstream.
+
+John reports that the recently merged commit 1a8e1cef7603 ("arm64: use
+both ZONE_DMA and ZONE_DMA32") breaks the boot on his DB845C board:
+
+  | Booting Linux on physical CPU 0x0000000000 [0x517f803c]
+  | Linux version 5.4.0-mainline-10675-g957a03b9e38f
+  | Machine model: Thundercomm Dragonboard 845c
+  | [...]
+  | Built 1 zonelists, mobility grouping on.  Total pages: -188245
+  | Kernel command line: earlycon
+  | firmware_class.path=/vendor/firmware/ androidboot.hardware=db845c
+  | init=/init androidboot.boot_devices=soc/1d84000.ufshc
+  | printk.devkmsg=on buildvariant=userdebug root=/dev/sda2
+  | androidboot.bootdevice=1d84000.ufshc androidboot.serialno=c4e1189c
+  | androidboot.baseband=sda
+  | msm_drm.dsi_display0=dsi_lt9611_1080_video_display:
+  | androidboot.slot_suffix=_a skip_initramfs rootwait ro init=/init
+  |
+  | <hangs indefinitely here>
+
+This is because, when CONFIG_NUMA=n, zone_sizes_init() fails to handle
+memblocks that fall entirely within the ZONE_DMA region and erroneously ends up
+trying to add a negatively-sized region into the following ZONE_DMA32, which is
+later interpreted as a large unsigned region by the core MM code.
+
+Rework the non-NUMA implementation of zone_sizes_init() so that the start
+address of the memblock being processed is adjusted according to the end of the
+previous zone, which is then range-checked before updating the hole information
+of subsequent zones.
+
+Cc: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
+Cc: Christoph Hellwig <hch@lst.de>
+Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
+Link: https://lore.kernel.org/lkml/CALAqxLVVcsmFrDKLRGRq7GewcW405yTOxG=KR3csVzQ6bXutkA@mail.gmail.com
+Fixes: 1a8e1cef7603 ("arm64: use both ZONE_DMA and ZONE_DMA32")
+Reported-by: John Stultz <john.stultz@linaro.org>
+Tested-by: John Stultz <john.stultz@linaro.org>
+Signed-off-by: Will Deacon <will@kernel.org>
+Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
+---
+ arch/arm64/mm/init.c | 25 +++++++++++--------------
+ 1 file changed, 11 insertions(+), 14 deletions(-)
+
+--- a/arch/arm64/mm/init.c
++++ b/arch/arm64/mm/init.c
+@@ -208,15 +208,14 @@ static void __init zone_sizes_init(unsig
+ {
+ 	struct memblock_region *reg;
+ 	unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
+-	unsigned long max_dma32 = min;
+-	unsigned long max_dma = min;
++	unsigned long __maybe_unused max_dma, max_dma32;
+ 
+ 	memset(zone_size, 0, sizeof(zone_size));
+ 
++	max_dma = max_dma32 = min;
+ #ifdef CONFIG_ZONE_DMA
+-	max_dma = PFN_DOWN(arm64_dma_phys_limit);
++	max_dma = max_dma32 = PFN_DOWN(arm64_dma_phys_limit);
+ 	zone_size[ZONE_DMA] = max_dma - min;
+-	max_dma32 = max_dma;
+ #endif
+ #ifdef CONFIG_ZONE_DMA32
+ 	max_dma32 = PFN_DOWN(arm64_dma32_phys_limit);
+@@ -230,25 +229,23 @@ static void __init zone_sizes_init(unsig
+ 		unsigned long start = memblock_region_memory_base_pfn(reg);
+ 		unsigned long end = memblock_region_memory_end_pfn(reg);
+ 
+-		if (start >= max)
+-			continue;
+ #ifdef CONFIG_ZONE_DMA
+-		if (start < max_dma) {
+-			unsigned long dma_end = min_not_zero(end, max_dma);
++		if (start >= min && start < max_dma) {
++			unsigned long dma_end = min(end, max_dma);
+ 			zhole_size[ZONE_DMA] -= dma_end - start;
++			start = dma_end;
+ 		}
+ #endif
+ #ifdef CONFIG_ZONE_DMA32
+-		if (start < max_dma32) {
++		if (start >= max_dma && start < max_dma32) {
+ 			unsigned long dma32_end = min(end, max_dma32);
+-			unsigned long dma32_start = max(start, max_dma);
+-			zhole_size[ZONE_DMA32] -= dma32_end - dma32_start;
++			zhole_size[ZONE_DMA32] -= dma32_end - start;
++			start = dma32_end;
+ 		}
+ #endif
+-		if (end > max_dma32) {
++		if (start >= max_dma32 && start < max) {
+ 			unsigned long normal_end = min(end, max);
+-			unsigned long normal_start = max(start, max_dma32);
+-			zhole_size[ZONE_NORMAL] -= normal_end - normal_start;
++			zhole_size[ZONE_NORMAL] -= normal_end - start;
+ 		}
+ 	}
+