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Diffstat (limited to 'target/linux/bcm27xx/patches-5.4/950-0636-dma-contiguous-CMA-give-precedence-to-cmdline.patch')
-rw-r--r--target/linux/bcm27xx/patches-5.4/950-0636-dma-contiguous-CMA-give-precedence-to-cmdline.patch49
1 files changed, 49 insertions, 0 deletions
diff --git a/target/linux/bcm27xx/patches-5.4/950-0636-dma-contiguous-CMA-give-precedence-to-cmdline.patch b/target/linux/bcm27xx/patches-5.4/950-0636-dma-contiguous-CMA-give-precedence-to-cmdline.patch
new file mode 100644
index 0000000000..d3354bb9e1
--- /dev/null
+++ b/target/linux/bcm27xx/patches-5.4/950-0636-dma-contiguous-CMA-give-precedence-to-cmdline.patch
@@ -0,0 +1,49 @@
+From cf40e83d2b6fb6857b13df4c8d69cc4c45395ea2 Mon Sep 17 00:00:00 2001
+From: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
+Date: Fri, 10 Jan 2020 18:19:33 +0100
+Subject: [PATCH] dma-contiguous: CMA: give precedence to cmdline
+
+commit 8c8c5a4994a306c217fd061cbfc5903399fd4c1c upstream.
+
+Although the device tree might contain a reserved-memory DT node
+dedicated as the default CMA pool, users might want to change CMA's
+parameters using the kernel command line for debugging purposes and
+whatnot. Honor this by bypassing the reserved memory CMA setup, which
+will ultimately end up freeing the memblock and allow the command line
+CMA configuration routine to run.
+
+Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
+Reviewed-by: Phil Elwell <phil@raspberrypi.org>
+Signed-off-by: Christoph Hellwig <hch@lst.de>
+---
+ kernel/dma/contiguous.c | 9 ++++++++-
+ 1 file changed, 8 insertions(+), 1 deletion(-)
+
+--- a/kernel/dma/contiguous.c
++++ b/kernel/dma/contiguous.c
+@@ -301,9 +301,16 @@ static int __init rmem_cma_setup(struct
+ phys_addr_t align = PAGE_SIZE << max(MAX_ORDER - 1, pageblock_order);
+ phys_addr_t mask = align - 1;
+ unsigned long node = rmem->fdt_node;
++ bool default_cma = of_get_flat_dt_prop(node, "linux,cma-default", NULL);
+ struct cma *cma;
+ int err;
+
++ if (size_cmdline != -1 && default_cma) {
++ pr_info("Reserved memory: bypass %s node, using cmdline CMA params instead\n",
++ rmem->name);
++ return -EBUSY;
++ }
++
+ if (!of_get_flat_dt_prop(node, "reusable", NULL) ||
+ of_get_flat_dt_prop(node, "no-map", NULL))
+ return -EINVAL;
+@@ -321,7 +328,7 @@ static int __init rmem_cma_setup(struct
+ /* Architecture specific contiguous memory fixup. */
+ dma_contiguous_early_fixup(rmem->base, rmem->size);
+
+- if (of_get_flat_dt_prop(node, "linux,cma-default", NULL))
++ if (default_cma)
+ dma_contiguous_set_default(cma);
+
+ rmem->ops = &rmem_cma_ops;