[PATCH] of: of_reserved_mem: Increase limit for reserved_mem regions

[Patrick Daly]

The reserved_mem array must be statically allocated because it is used
prior to memblock being aware of all "no-map" or otherwise reserved
regions which have fixed physical addresses. Due to this limitation,
if one architecture/board has a large number of reserved_mem regions,
this limit must be raised for all.

In particular, certain new qcom boards currently have 63 reserved memory
regions, which when new features are added, pushes them over the existing
limit of 64.

A generalized breakdown by region type:
13 for linux-loaded device firmware
9 for guest-vms or inter-vm communication
15 cma heaps/dma-buf heaps
24 for bootloaders/hypervisor/secure-world devices or software
2 misc

Although this number could be reduced by a minor amount by combining
physically adjacent regions, this comes at the cost of losing
documention on what/who the regions are used by. In addition, combining
adjacent regions is not possible if there are phandles in devicetree
referring to the regions in question, such as "memory-region".

Vmlinux before:
text      data      bss     dec       hex      filename
31030829  15807732  588524  47427085  2d3ae0d  dist/vmlinux

Vmlinux after:
text      data      bss     dec       hex      filename
31030877  15807668  592108  47430653  2d3bbfd  dist/vmlinux

Signed-off-by: Patrick Daly <quic_pdaly at quicinc.com>
---
 drivers/of/of_reserved_mem.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/of/of_reserved_mem.c b/drivers/of/of_reserved_mem.c
index 75caa6f..de0cdda 100644
--- a/drivers/of/of_reserved_mem.c
+++ b/drivers/of/of_reserved_mem.c
@@ -26,7 +26,7 @@
 
 #include "of_private.h"
 
-#define MAX_RESERVED_REGIONS	64
+#define MAX_RESERVED_REGIONS	128
 static struct reserved_mem reserved_mem[MAX_RESERVED_REGIONS];
 static int reserved_mem_count;
 
-- 
2.7.4