path: root/drivers/irqchip
diff options
authorMatt Redfearn <matt.redfearn@mips.com>2017-11-09 11:02:45 +0000
committerMarc Zyngier <marc.zyngier@arm.com>2017-11-09 11:35:28 +0000
commit666740fde412567aa0a8ea251ffee3004a6fa3a6 (patch)
tree8bae9e944a171503cca430af03bcf0ee4956eb4e /drivers/irqchip
parent1f19aee0ec404112cec08f0c852fcd291690fbc7 (diff)
irqchip: mips-gic: Print warning if inherited GIC base is used
If the physical address of the GIC resource cannot be read from device tree, then the code falls back to reading it from the gcr_gic_base register. Hopefully this has been set to a sane value by the bootloader or some platform code, but is defined by the hardware manual to have "undefined" reset state. Using it as the address at which the GIC will be mapped into physical memory space can therefore be risky if it has not been initialised, since it may result in the GIC being mapped to an effectively random address anywhere in physical memory, where it might conflict with peripherals or RAM and lead to weird crashes. Since a "sane value" is very platform specific because it is particular to the platform's memory map, it is difficult to test for. At the very least, a warning message should be printed in the case that we trust the inherited value. Reported-by: Amit Kama <amit.kama@satixfy.com> Signed-off-by: Matt Redfearn <matt.redfearn@mips.com> Reviewed-by: Paul Burton <paul.burton@mips.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Diffstat (limited to 'drivers/irqchip')
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-mips-gic.c b/drivers/irqchip/irq-mips-gic.c
index 9b768899f07b..ef92a4d2038e 100644
--- a/drivers/irqchip/irq-mips-gic.c
+++ b/drivers/irqchip/irq-mips-gic.c
@@ -701,6 +701,8 @@ static int __init gic_of_init(struct device_node *node,
gic_base = read_gcr_gic_base() &
gic_len = 0x20000;
+ pr_warn("Using inherited base address %pa\n",
+ &gic_base);
} else {
pr_err("Failed to get memory range\n");
return -ENODEV;

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