* Re: [patches] [PATCH] irqchip/riscv-plic: fix address alignment of the plic enable bits
2017-12-19 7:44 [PATCH] irqchip/riscv-plic: fix address alignment of the plic enable bits Zong Li
@ 2017-12-21 18:50 ` Palmer Dabbelt
0 siblings, 0 replies; 2+ messages in thread
From: Palmer Dabbelt @ 2017-12-21 18:50 UTC (permalink / raw)
To: zongbox
Cc: tglx, jason, marc.zyngier, albert, linux-kernel, patches,
greentime, zong, zongbox
On Mon, 18 Dec 2017 23:44:38 PST (-0800), zongbox@gmail.com wrote:
> When the interrupt sourece id > 31, the register address is not 4 byte
> alignment. Arithmetic on void pointer has no size extension, it just
> add the result of 'hwirq/32' directly.
>
> Signed-off-by: Zong Li <zongbox@gmail.com>
> ---
> drivers/irqchip/irq-riscv-plic.c | 15 +++++++++------
> 1 file changed, 9 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/irqchip/irq-riscv-plic.c b/drivers/irqchip/irq-riscv-plic.c
> index b5182b4..0a43763 100644
> --- a/drivers/irqchip/irq-riscv-plic.c
> +++ b/drivers/irqchip/irq-riscv-plic.c
> @@ -92,6 +92,8 @@
> */
> #define ENABLE_BASE 0x2000
> #define ENABLE_PER_HART 0x80
> +#define ENABLE_SOURCES 32
> +#define ENABLE_SOURCES_OFFSET 4
>
> /*
> * Each hart context has a set of control registers associated with it. Right
> @@ -128,9 +130,10 @@ struct plic_data {
>
> /* Addressing helper functions. */
> static inline
> -void __iomem *plic_enable_vector(struct plic_data *data, int contextid)
> +void __iomem *plic_enable_vector(struct plic_data *data, int contextid, int hwirq)
> {
> - return data->reg + ENABLE_BASE + contextid * ENABLE_PER_HART;
> + return data->reg + ENABLE_BASE + contextid * ENABLE_PER_HART +
> + (hwirq / ENABLE_SOURCES) * ENABLE_SOURCES_OFFSET;
> }
>
> static inline
> @@ -172,8 +175,8 @@ void plic_complete(struct plic_data *data, int contextid, u32 claim)
> /* Explicit interrupt masking. */
> static void plic_disable(struct plic_data *data, int contextid, int hwirq)
> {
> - void __iomem *reg = plic_enable_vector(data, contextid) + (hwirq / 32);
> - u32 mask = ~(1 << (hwirq % 32));
> + void __iomem *reg = plic_enable_vector(data, contextid, hwirq);
> + u32 mask = ~(1 << (hwirq % ENABLE_SOURCES));
>
> spin_lock(&data->lock);
> writel(readl(reg) & mask, reg);
> @@ -182,8 +185,8 @@ static void plic_disable(struct plic_data *data, int contextid, int hwirq)
>
> static void plic_enable(struct plic_data *data, int contextid, int hwirq)
> {
> - void __iomem *reg = plic_enable_vector(data, contextid) + (hwirq / 32);
> - u32 bit = 1 << (hwirq % 32);
> + void __iomem *reg = plic_enable_vector(data, contextid, hwirq);
> + u32 bit = 1 << (hwirq % ENABLE_SOURCES);
>
> spin_lock(&data->lock);
> writel(readl(reg) | bit, reg);
Whoops, sorry about that. I think it's cleaner to use a 'u32 *' instead of
'void *' here, something more like this (which I haven't even compiled)
commit 2424a65ce079ecbe16fbedc704b88b6f04f8b97a
Author: Palmer Dabbelt <palmer@sifive.com>
Date: Wed Dec 20 19:31:41 2017 -0800
void* -> u32* in PLIC
diff --git a/drivers/irqchip/irq-riscv-plic.c b/drivers/irqchip/irq-riscv-plic.c
index b5182b43b377..99e79713abc6 100644
--- a/drivers/irqchip/irq-riscv-plic.c
+++ b/drivers/irqchip/irq-riscv-plic.c
@@ -128,25 +128,25 @@ struct plic_data {
/* Addressing helper functions. */
static inline
-void __iomem *plic_enable_vector(struct plic_data *data, int contextid)
+u32 __iomem *plic_enable_vector(struct plic_data *data, int contextid)
{
return data->reg + ENABLE_BASE + contextid * ENABLE_PER_HART;
}
static inline
-void __iomem *plic_priority(struct plic_data *data, int hwirq)
+u32 __iomem *plic_priority(struct plic_data *data, int hwirq)
{
return data->reg + PRIORITY_BASE + hwirq * PRIORITY_PER_ID;
}
static inline
-void __iomem *plic_hart_threshold(struct plic_data *data, int contextid)
+u32 __iomem *plic_hart_threshold(struct plic_data *data, int contextid)
{
return data->reg + CONTEXT_BASE + CONTEXT_PER_HART * contextid + CONTEXT_THRESHOLD;
}
static inline
-void __iomem *plic_hart_claim(struct plic_data *data, int contextid)
+u32 __iomem *plic_hart_claim(struct plic_data *data, int contextid)
{
return data->reg + CONTEXT_BASE + CONTEXT_PER_HART * contextid + CONTEXT_CLAIM;
}
@@ -172,7 +172,7 @@ void plic_complete(struct plic_data *data, int contextid, u32 claim)
/* Explicit interrupt masking. */
static void plic_disable(struct plic_data *data, int contextid, int hwirq)
{
- void __iomem *reg = plic_enable_vector(data, contextid) + (hwirq / 32);
+ u32 __iomem *reg = plic_enable_vector(data, contextid) + (hwirq / 32);
u32 mask = ~(1 << (hwirq % 32));
spin_lock(&data->lock);
@@ -182,7 +182,7 @@ static void plic_disable(struct plic_data *data, int contextid, int hwirq)
static void plic_enable(struct plic_data *data, int contextid, int hwirq)
{
- void __iomem *reg = plic_enable_vector(data, contextid) + (hwirq / 32);
+ u32 __iomem *reg = plic_enable_vector(data, contextid) + (hwirq / 32);
u32 bit = 1 << (hwirq % 32);
spin_lock(&data->lock);
Note that the PLIC driver isn't upstream yet, and hasn't been reviewed because
(as you've discovered) it's a bit of a mess. Thanks for the patch, I'll be
sure to fix it up before sending out the PLIC driver for review.
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