tree 14d8296031ab47dc34c6d529719bf9f6634ef88e
parent df9bf949642604d599c471e854aa638f3b2f9ffe
author Abhijeet Dharmapurikar <adharmap@codeaurora.org> 1453183233 -0800
committer David Collins <collinsd@codeaurora.org> 1484247661 -0800

spmi: pmic_arb: block access of invalid read and writes

The system crashes due to bad access when reading from an non configured
peripheral and when writing to peripheral which is not owned by current
ee. This patch verifies ownership to avoid crashing on
write.

For reads, since the forward mapping table, data_channel->ppid, is
towards the end of the block, we use the core size to figure the
max number of ppids supported. The table starts at an offset of 0x800
within the block, so size - 0x800 will give us the area used by the
table. Since each table is 4 bytes long (core_size - 0x800) / 4 will
gives us the number of data_channel supported.

This new protection is functional on hw v2.

Change-Id: I74e3452963a7dda9a8c8aaef76de3117cabc454b
Signed-off-by: Abhijeet Dharmapurikar <adharmap@codeaurora.org>
[collinsd: fix minor merge conflict and checkpatch warning]
Signed-off-by: David Collins <collinsd@codeaurora.org>