[PATCH v3 1/2] irqchip/sifive-plic: Improve naming scheme for per context offsets
Niklas Cassel
Niklas.Cassel at wdc.com
Wed Mar 2 05:15:52 PST 2022
From: Niklas Cassel <niklas.cassel at wdc.com>
The PLIC supports a fixed number of contexts (15872).
Each context has fixed register offsets in PLIC.
The number of contexts that we need to initialize depends on the privilege
modes supported by each hart. Therefore, this mapping between PLIC context
registers to hart privilege modes is platform specific, and is currently
supplied via device tree.
For example, canaan,k210 has the following mapping:
Context0: hart0 M-mode
Context1: hart0 S-mode
Context2: hart1 M-mode
Context3: hart1 S-mode
While sifive,fu540 has the following mapping:
Context0: hart0 M-mode
Context1: hart1 M-mode
Context2: hart1 S-mode
Because the number of contexts per hart is not fixed, the names
ENABLE_PER_HART and CONTEXT_PER_HART for the register offsets are quite
confusing and might mislead the reader to think that these are fixed
register offsets per hart.
Rename the offsets to more clearly highlight that these are per PLIC
context and not per hart.
Signed-off-by: Niklas Cassel <niklas.cassel at wdc.com>
Reviewed-by: Anup Patel <anup at brainfault.org>
---
drivers/irqchip/irq-sifive-plic.c | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)
diff --git a/drivers/irqchip/irq-sifive-plic.c b/drivers/irqchip/irq-sifive-plic.c
index 09cc98266d30..fc9da94eb816 100644
--- a/drivers/irqchip/irq-sifive-plic.c
+++ b/drivers/irqchip/irq-sifive-plic.c
@@ -44,8 +44,8 @@
* Each hart context has a vector of interrupt enable bits associated with it.
* There's one bit for each interrupt source.
*/
-#define ENABLE_BASE 0x2000
-#define ENABLE_PER_HART 0x80
+#define CONTEXT_ENABLE_BASE 0x2000
+#define CONTEXT_ENABLE_SIZE 0x80
/*
* Each hart context has a set of control registers associated with it. Right
@@ -53,7 +53,7 @@
* take an interrupt, and a register to claim interrupts.
*/
#define CONTEXT_BASE 0x200000
-#define CONTEXT_PER_HART 0x1000
+#define CONTEXT_SIZE 0x1000
#define CONTEXT_THRESHOLD 0x00
#define CONTEXT_CLAIM 0x04
@@ -361,11 +361,11 @@ static int __init plic_init(struct device_node *node,
cpumask_set_cpu(cpu, &priv->lmask);
handler->present = true;
- handler->hart_base =
- priv->regs + CONTEXT_BASE + i * CONTEXT_PER_HART;
+ handler->hart_base = priv->regs + CONTEXT_BASE +
+ i * CONTEXT_SIZE;
raw_spin_lock_init(&handler->enable_lock);
- handler->enable_base =
- priv->regs + ENABLE_BASE + i * ENABLE_PER_HART;
+ handler->enable_base = priv->regs + CONTEXT_ENABLE_BASE +
+ i * CONTEXT_ENABLE_SIZE;
handler->priv = priv;
done:
for (hwirq = 1; hwirq <= nr_irqs; hwirq++)
--
2.35.1
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