From: Guo Ren guoren@linux.alibaba.com
[ Upstream commit 1d4df649cbb4b26d19bea38ecff4b65b10a1bbca ]
The thead,c900-plic has been used in opensbi to distinguish PLIC [1]. Although PLICs have the same behaviors in Linux, they are different hardware with some custom initializing in firmware(opensbi).
Qute opensbi patch commit-msg by Samuel:
The T-HEAD PLIC implementation requires setting a delegation bit to allow access from S-mode. Now that the T-HEAD PLIC has its own compatible string, set this bit automatically from the PLIC driver, instead of reaching into the PLIC's MMIO space from another driver.
[1]: https://github.com/riscv-software-src/opensbi/commit/78c2b19218bd62653b9fb31...
Signed-off-by: Guo Ren guoren@linux.alibaba.com Cc: Anup Patel anup@brainfault.org Cc: Marc Zyngier maz@kernel.org Cc: Palmer Dabbelt palmer@dabbelt.com Cc: Samuel Holland samuel@sholland.org Cc: Thomas Gleixner tglx@linutronix.de Tested-by: Samuel Holland samuel@sholland.org Signed-off-by: Marc Zyngier maz@kernel.org Link: https://lore.kernel.org/r/20220130135634.1213301-3-guoren@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/irqchip/irq-sifive-plic.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/drivers/irqchip/irq-sifive-plic.c b/drivers/irqchip/irq-sifive-plic.c index 259065d271ef0..09cc98266d30f 100644 --- a/drivers/irqchip/irq-sifive-plic.c +++ b/drivers/irqchip/irq-sifive-plic.c @@ -398,3 +398,4 @@ static int __init plic_init(struct device_node *node,
IRQCHIP_DECLARE(sifive_plic, "sifive,plic-1.0.0", plic_init); IRQCHIP_DECLARE(riscv_plic0, "riscv,plic0", plic_init); /* for legacy systems */ +IRQCHIP_DECLARE(thead_c900_plic, "thead,c900-plic", plic_init); /* for firmware driver */