2019-12-05 02:41:56

by Guenter Roeck

Subject: [PATCH] nios2: Fix ioremap

Commit 5ace77e0b41a ("nios2: remove __ioremap") removed the following code,
with the argument that cacheflag is always 0 and the expression would
therefore always be false.

if (IS_MAPPABLE_UNCACHEABLE(phys_addr) &&
IS_MAPPABLE_UNCACHEABLE(last_addr) &&
!(cacheflag & _PAGE_CACHED))
return (void __iomem *)(CONFIG_NIOS2_IO_REGION_BASE + phys_addr);

This did not take the "!" in the expression into account. Result is that
nios2 images no longer boot. Restoring the removed code fixes the problem.

Fixes: 5ace77e0b41a ("nios2: remove __ioremap")
Cc: Christoph Hellwig <[email protected]>
Signed-off-by: Guenter Roeck <[email protected]>
---
arch/nios2/mm/ioremap.c | 8 ++++++++
1 file changed, 8 insertions(+)

diff --git a/arch/nios2/mm/ioremap.c b/arch/nios2/mm/ioremap.c
index b56af759dcdf..819bdfcc2e71 100644
--- a/arch/nios2/mm/ioremap.c
+++ b/arch/nios2/mm/ioremap.c
@@ -138,6 +138,14 @@ void __iomem *ioremap(unsigned long phys_addr, unsigned long size)
return NULL;
}

+ /*
+ * Map uncached objects in the low part of address space to
+ * CONFIG_NIOS2_IO_REGION_BASE
+ */
+ if (IS_MAPPABLE_UNCACHEABLE(phys_addr) &&
+ IS_MAPPABLE_UNCACHEABLE(last_addr))
+ return (void __iomem *)(CONFIG_NIOS2_IO_REGION_BASE + phys_addr);
+
/* Mappings have to be page-aligned */
offset = phys_addr & ~PAGE_MASK;
phys_addr &= PAGE_MASK;
--
2.17.1

2019-12-05 14:27:21

by Christoph Hellwig

Subject: Re: [PATCH] nios2: Fix ioremap

Looks good:

Reviewed-by: Christoph Hellwig <[email protected]>

2019-12-12 08:58:44

by Tan, Ley Foon

Subject: RE: [PATCH] nios2: Fix ioremap

> -----Original Message-----
> From: Guenter Roeck <[email protected]> On Behalf Of Guenter Roeck
> Sent: Thursday, December 5, 2019 10:41 AM
> To: Ley Foon Tan <[email protected]>
> Cc: [email protected]; [email protected];
> Guenter Roeck <[email protected]>; Christoph Hellwig <[email protected]>
> Subject: [PATCH] nios2: Fix ioremap
>
> Commit 5ace77e0b41a ("nios2: remove __ioremap") removed the following
> code, with the argument that cacheflag is always 0 and the expression would
> therefore always be false.
>
> if (IS_MAPPABLE_UNCACHEABLE(phys_addr) &&
> IS_MAPPABLE_UNCACHEABLE(last_addr) &&
> !(cacheflag & _PAGE_CACHED))
> return (void __iomem *)(CONFIG_NIOS2_IO_REGION_BASE +
> phys_addr);
>
> This did not take the "!" in the expression into account. Result is that
> nios2 images no longer boot. Restoring the removed code fixes the problem.
>
> Fixes: 5ace77e0b41a ("nios2: remove __ioremap")
> Cc: Christoph Hellwig <[email protected]>
> Signed-off-by: Guenter Roeck <[email protected]>

Will add to next rc.
Thanks.

Acked-by: Ley Foon Tan <[email protected]>