FROMLIST: of: of_reserved_mem: Increase limit for reserved_mem regions

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
refering to the regions in question, such as "memory-region".

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

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

Bug: 229767760
Link: https://lore.kernel.org/linux-devicetree/1650488954-26662-1-git-send-email-quic_pdaly@quicinc.com/T/#u
Change-Id: I2bdc6ad1ecfe273aad3c72390283b6d1247b18c3
Signed-off-by: Patrick Daly <quic_pdaly@quicinc.com>
Signed-off-by: Sukadev Bhattiprolu <quic_sukadev@quicinc.com>
This commit is contained in:
Patrick Daly 2022-04-19 15:38:18 -07:00 committed by Suren Baghdasaryan
parent 648e73245b
commit f5ba378e89
1 changed files with 1 additions and 1 deletions

View File

@ -25,7 +25,7 @@
#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;