diff mbox series

[v7,09/10] um: Add dummy implementation for IO memcpy/memset

Message ID 20240930132321.2785718-10-jvetter@kalrayinc.com (mailing list archive)
State Not Applicable
Headers show
Series Consolidate IO memcpy functions | expand

Commit Message

Julian Vetter Sept. 30, 2024, 1:23 p.m. UTC 
The um arch is the only architecture that sets the config 'NO_IOMEM',
yet drivers that use IO memory can be selected. In order to make these
drivers happy we add a dummy implementation for memcpy_{from,to}io and
memset_io functions.

Reviewed-by: Yann Sionneau <ysionneau@kalrayinc.com>
Signed-off-by: Julian Vetter <jvetter@kalrayinc.com>
---
Changes for v7:
- New patch
---
 arch/um/include/asm/io.h | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

Comments

Johannes Berg Oct. 1, 2024, 12:53 p.m. UTC | #1 
On Mon, 2024-09-30 at 15:23 +0200, Julian Vetter wrote:
> The um arch is the only architecture that sets the config 'NO_IOMEM',
> yet drivers that use IO memory can be selected. In order to make these
> drivers happy we add a dummy implementation for memcpy_{from,to}io and
> memset_io functions.

Maybe I'm just not understanding this series, but how does this work
with lib/logic_iomem.c?

You're adding these inlines unconditionally, so if this included
logic_io.h, you should get symbol conflicts?

Also not sure these functions should/need to do anything at all, there's
no IO memory on ARCH=um in case of not having logic_io.h. Maybe even
BUG_ON() or something? It can't be reachable (under correct drivers)
since ioremap() always returns NULL (without logic_iomem).

I think Arnd also said that other architectures might want to use
logic_iomem, though I don't see any now.

johannes
diff mbox series

Patch

diff --git a/arch/um/include/asm/io.h b/arch/um/include/asm/io.h
index 9ea42cc746d9..f02f40609798 100644
--- a/arch/um/include/asm/io.h
+++ b/arch/um/include/asm/io.h
@@ -21,6 +21,23 @@  static inline void iounmap(void __iomem *addr)
 }
 #endif /* iounmap */
 
+static inline void memset_io(volatile void __iomem *dst, int c, size_t count)
+{
+	memset((void *)dst, c, count);
+}
+
+static inline void memcpy_toio(volatile void __iomem *to, const void *from,
+			       size_t count)
+{
+	memcpy((void *)to, from, count);
+}
+
+static inline void memcpy_fromio(void *to, const volatile void __iomem *from,
+				 size_t count)
+{
+	memcpy(to, (void *)from, count);
+}
+
 #include <asm-generic/io.h>
 
 #endif