[PATCH] smc91x: remove ARM hack for unaligned 16-bit writes
Russell King - ARM Linux
linux at armlinux.org.uk
Thu Aug 25 15:37:43 PDT 2016
On Thu, Aug 25, 2016 at 08:02:35PM +0200, Robert Jarzmik wrote:
> Arnd Bergmann <arnd at arndb.de> writes:
>
> > On Thursday, August 25, 2016 4:43:04 PM CEST Arnd Bergmann wrote:
> >> drivers/net/ethernet/smsc/smc91x.h | 50 +++++++++++++++++++++++---------------
> >> 1 file changed, 30 insertions(+), 20 deletions(-)
> >>
> >> While this patch fixes one bug on Neponset, it probably doesn't address
> >> the one that Russell ran into first, so this is for review only for now,
> >> until the remaining problem(s) have been worked out.
> >>
> >
> > The comment should have been on another patch, my mistake. please
> > see v2.
> >
> > Arnd
>
> Hi Arnd,
>
> I didn't review the patch thoroughly, but I launched your 2 patches in my pxa
> little farm.
>
> The result is that lubbock and mainstone are all right, but zylonite is broken
> (ie. networkless). I removed then these 2 patches and zylonite worked again.
>
> I have also an error message on the console on a "broken" zylonite :
> Changing smcs91x MAC address to 08:00:3e:26:0a:5b: ifconfig: SIOCSIFHWADDR:
> Device or resource busy
>
> I reran the test twice (2 times with your patches, 2 times without), the result
> looks consistent, ie. zylonite doesn't really like them.
Please try the patch below. I sent this to Will a few days ago, as
he said (on irc) that he was also seeing problems on a platform he
had, but I've yet to hear back. I've not posted it yet because I
haven't got around to writing a commit description for it.
It does require that at least one of 8-bit or 16-bit accesses are
supported, but I think that's already true.
8<========
From: Russell King <rmk+kernel at armlinux.org.uk>
Subject: [PATCH] net: smc91x: fix SMC accesses
Signed-off-by: Russell King <rmk+kernel at armlinux.org.uk>
---
drivers/net/ethernet/smsc/smc91x.h | 65 ++++++++++++++++++++++++++------------
1 file changed, 45 insertions(+), 20 deletions(-)
diff --git a/drivers/net/ethernet/smsc/smc91x.h b/drivers/net/ethernet/smsc/smc91x.h
index 1a55c7976df0..e17671c9d1b0 100644
--- a/drivers/net/ethernet/smsc/smc91x.h
+++ b/drivers/net/ethernet/smsc/smc91x.h
@@ -37,6 +37,27 @@
#include <linux/smc91x.h>
/*
+ * Any 16-bit access is performed with two 8-bit accesses if the hardware
+ * can't do it directly. Most registers are 16-bit so those are mandatory.
+ */
+#define SMC_outw_b(x, a, r) \
+ do { \
+ unsigned int __val16 = (x); \
+ unsigned int __reg = (r); \
+ SMC_outb(__val16, a, __reg); \
+ SMC_outb(__val16 >> 8, a, __reg + (1 << SMC_IO_SHIFT)); \
+ } while (0)
+
+#define SMC_inw_b(a, r) \
+ ({ \
+ unsigned int __val16; \
+ unsigned int __reg = r; \
+ __val16 = SMC_inb(a, __reg); \
+ __val16 |= SMC_inb(a, __reg + (1 << SMC_IO_SHIFT)) << 8; \
+ __val16; \
+ })
+
+/*
* Define your architecture specific bus configuration parameters here.
*/
@@ -55,10 +76,30 @@
#define SMC_IO_SHIFT (lp->io_shift)
#define SMC_inb(a, r) readb((a) + (r))
-#define SMC_inw(a, r) readw((a) + (r))
+#define SMC_inw(a, r) \
+ ({ \
+ unsigned int __smc_r = r; \
+ SMC_16BIT(lp) ? readw((a) + __smc_r) : \
+ SMC_8BIT(lp) ? SMC_inw_b(a, __smc_r) : \
+ ({ BUG(); 0; }); \
+ })
+
#define SMC_inl(a, r) readl((a) + (r))
#define SMC_outb(v, a, r) writeb(v, (a) + (r))
+#define SMC_outw(v, a, r) \
+ do { \
+ unsigned int __v = v, __smc_r = r; \
+ if (SMC_16BIT(lp)) \
+ __SMC_outw(__v, a, __smc_r); \
+ else if (SMC_8BIT(lp)) \
+ SMC_outw_b(__v, a, __smc_r); \
+ else \
+ BUG(); \
+ } while (0)
+
#define SMC_outl(v, a, r) writel(v, (a) + (r))
+#define SMC_insb(a, r, p, l) readsb((a) + (r), p, l)
+#define SMC_outsb(a, r, p, l) writesb((a) + (r), p, l)
#define SMC_insw(a, r, p, l) readsw((a) + (r), p, l)
#define SMC_outsw(a, r, p, l) writesw((a) + (r), p, l)
#define SMC_insl(a, r, p, l) readsl((a) + (r), p, l)
@@ -66,7 +107,7 @@
#define SMC_IRQ_FLAGS (-1) /* from resource */
/* We actually can't write halfwords properly if not word aligned */
-static inline void SMC_outw(u16 val, void __iomem *ioaddr, int reg)
+static inline void __SMC_outw(u16 val, void __iomem *ioaddr, int reg)
{
if ((machine_is_mainstone() || machine_is_stargate2() ||
machine_is_pxa_idp()) && reg & 2) {
@@ -416,24 +457,8 @@ smc_pxa_dma_insw(void __iomem *ioaddr, struct smc_local *lp, int reg, int dma,
#if ! SMC_CAN_USE_16BIT
-/*
- * Any 16-bit access is performed with two 8-bit accesses if the hardware
- * can't do it directly. Most registers are 16-bit so those are mandatory.
- */
-#define SMC_outw(x, ioaddr, reg) \
- do { \
- unsigned int __val16 = (x); \
- SMC_outb( __val16, ioaddr, reg ); \
- SMC_outb( __val16 >> 8, ioaddr, reg + (1 << SMC_IO_SHIFT));\
- } while (0)
-#define SMC_inw(ioaddr, reg) \
- ({ \
- unsigned int __val16; \
- __val16 = SMC_inb( ioaddr, reg ); \
- __val16 |= SMC_inb( ioaddr, reg + (1 << SMC_IO_SHIFT)) << 8; \
- __val16; \
- })
-
+#define SMC_outw(x, ioaddr, reg) SMC_outw_b(x, ioaddr, reg)
+#define SMC_inw(ioaddr, reg) SMC_inw_b(ioaddr, reg)
#define SMC_insw(a, r, p, l) BUG()
#define SMC_outsw(a, r, p, l) BUG()
--
2.1.0
--
RMK's Patch system: http://www.armlinux.org.uk/developer/patches/
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