Re: [PATCH v4 2/5] irqchip: gicv3-its: use 64KB page as default granule

2015-03-06 Thread Marc Zyngier
On 06/03/15 04:13, Yun Wu wrote:
> The field of page size in register GITS_BASERn might be read-only
> if an implementation only supports a single, fixed page size. But
> currently the ITS driver will throw out an error when PAGE_SIZE
> is less than the minimum size supported by an ITS. So addressing
> this problem by using 64KB pages as default granule for all the
> ITS base tables.
> 
> Acked-by: Marc Zyngier 
> Signed-off-by: Yun Wu 
> ---
>  drivers/irqchip/irq-gic-v3-its.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/irqchip/irq-gic-v3-its.c 
> b/drivers/irqchip/irq-gic-v3-its.c
> index 69eeea3..f5bfa42 100644
> --- a/drivers/irqchip/irq-gic-v3-its.c
> +++ b/drivers/irqchip/irq-gic-v3-its.c
> @@ -800,7 +800,7 @@ static int its_alloc_tables(struct its_node *its)
>  {
>   int err;
>   int i;
> - int psz = PAGE_SIZE;
> + int psz = SZ_64K;
>   u64 shr = GITS_BASER_InnerShareable;
> 
>   for (i = 0; i < GITS_BASER_NR_REGS; i++) {

Just went through a test run with this, and this breaks any non Device
Table allocation when PAGE_SIZE != 64K.

The following hunk fixes it:

@@ -806,7 +806,7 @@ static int its_alloc_tables(struct its_node *its)
u64 val = readq_relaxed(its->base + GITS_BASER + i * 8);
u64 type = GITS_BASER_TYPE(val);
u64 entry_size = GITS_BASER_ENTRY_SIZE(val);
-   int order = 0;
+   int order = get_order(psz);
int alloc_size;
u64 tmp;
void *base;

I'll fold it in to the original patch, but I'd be grateful if you could
do a slightly more thorough testing before sending patches.

Thanks,

M.
-- 
Jazz is not dead. It just smells funny...
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[PATCH v4 2/5] irqchip: gicv3-its: use 64KB page as default granule

2015-03-05 Thread Yun Wu
The field of page size in register GITS_BASERn might be read-only
if an implementation only supports a single, fixed page size. But
currently the ITS driver will throw out an error when PAGE_SIZE
is less than the minimum size supported by an ITS. So addressing
this problem by using 64KB pages as default granule for all the
ITS base tables.

Acked-by: Marc Zyngier 
Signed-off-by: Yun Wu 
---
 drivers/irqchip/irq-gic-v3-its.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index 69eeea3..f5bfa42 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -800,7 +800,7 @@ static int its_alloc_tables(struct its_node *its)
 {
int err;
int i;
-   int psz = PAGE_SIZE;
+   int psz = SZ_64K;
u64 shr = GITS_BASER_InnerShareable;

for (i = 0; i < GITS_BASER_NR_REGS; i++) {
--
1.8.0


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