On Mon, Sep 01, 2014 at 06:32:45PM +0100, Graeme Gregory wrote:

On Mon, Sep 01, 2014 at 07:11:44PM +0200, Arnd Bergmann wrote:

quoted

On Monday 01 September 2014 18:04:47 Catalin Marinas wrote:

quoted

On Mon, Sep 01, 2014 at 04:06:00PM +0100, Hanjun Guo wrote:

quoted

+#ifdef CONFIG_ACPI
+/* Configure some sensible defaults for ACPI mode */
+static int smsc911x_probe_config_acpi(struct smsc911x_platform_config *config,
+                                 acpi_handle *ahandle)
+{
+     if (!ahandle)
+             return -ENOSYS;
+
+     config->phy_interface = PHY_INTERFACE_MODE_MII;
+
+     config->flags |= SMSC911X_USE_32BIT;
+
+     config->irq_polarity = SMSC911X_IRQ_POLARITY_ACTIVE_HIGH;
+
+     config->irq_type = SMSC911X_IRQ_TYPE_PUSH_PULL;
+
+     return 0;
+}
+#else

I don't like this and it shows issues we have with ACPI on certain ARM
platforms. You hard-code these values to match the Juno platform. What
if we get another SoC which has different configuration here? For DT, we
have the smsc911x_probe_config_dt() which reads the relevant information
from DT. I think this kind of configuration would be more suitable as
_DSD properties and sharing the similar names with DT (but we go back to
the question about who's in charge of the _DSD properties).

Good point, I totally missed that.

There is of course the possibility to set those values based on the
acpi_device_id, but that is exactly the part that _DSD is trying to
avoid.

This will of course most likely be replaced by _DSD values. I just
hardcoded for now as _DSD is not yet in the kernel and issues around
maintenance of bindings are not solved (unless this happened at KS where
I was not present).

Not much at the KS, I think it will need to be followed up on lkml
(https://lkml.org/lkml/2014/8/17/10 is the last I'm aware of, not sure
about any updates in the meantime).

While the above gets sorted, what's the position from an ARM
perspective (and covered by Documentation/arm64/arm-acpi.txt)? I think
the "Device Enumeration" section in this document is fine, it's just the
kernel infrastructure missing.

Alternatively, you can say _DSD is not allowed (yet?) but I don't
particularly like basing the configuration on acpi_device_id like in
this patch. Which would leave us with ignoring any SoC containing
devices that require such specific configuration.

-- 
Catalin