Re: [Linaro-acpi] [PATCH V1 07/11] XEN / PCI: Remove the dependence on arch x86 when PCI_MMCONFIG=y

From: Boris Ostrovsky
Date: Wed Oct 28 2015 - 10:09:00 EST


On 10/28/2015 09:45 AM, Hanjun Guo wrote:
On 10/28/2015 06:56 PM, Tomasz Nowicki wrote:
On 28.10.2015 11:49, Stefano Stabellini wrote:
On Tue, 27 Oct 2015, Boris Ostrovsky wrote:
On 10/27/2015 12:47 PM, Tomasz Nowicki wrote:
+ Stefano

On 27.10.2015 17:38, Tomasz Nowicki wrote:
From: Hanjun Guo <hanjun.guo@xxxxxxxxxx>

In drivers/xen/pci.c, there are arch x86 dependent codes when
CONFIG_PCI_MMCONFIG is enabled, since CONFIG_PCI_MMCONFIG
depends on ACPI, so this will prevent XEN PCI running on other
architectures using ACPI with PCI_MMCONFIG enabled (such as ARM64).

Fortunatly, it can be sloved in a simple way. In drivers/xen/pci.c,
the only x86 dependent code is if ((pci_probe & PCI_PROBE_MMCONF)
== 0),
and it's defined in asm/pci_x86.h, the code means that
if the PCI resource is not probed in PCI_PROBE_MMCONF way, just
ingnore the xen mcfg init. Actually this is duplicate, because
if PCI resource is not probed in PCI_PROBE_MMCONF way, the
pci_mmconfig_list will be empty, and the if (list_empty())
after it will do the same job.

So just remove the arch related code and the head file, this
will be no functional change for x86, and also makes xen/pci.c
usable for other architectures.

Signed-off-by: Hanjun Guo <hanjun.guo@xxxxxxxxxx>
CC: Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx>
CC: Boris Ostrovsky <boris.ostrovsky@xxxxxxxxxx>
---
drivers/xen/pci.c | 6 ------
1 file changed, 6 deletions(-)

diff --git a/drivers/xen/pci.c b/drivers/xen/pci.c
index 6785ebb..9a8dbe3 100644
--- a/drivers/xen/pci.c
+++ b/drivers/xen/pci.c
@@ -28,9 +28,6 @@
#include <asm/xen/hypervisor.h>
#include <asm/xen/hypercall.h>
#include "../pci/pci.h"
-#ifdef CONFIG_PCI_MMCONFIG
-#include <asm/pci_x86.h>
-#endif

Assuming this still compiles on x86 now that this include file is
removed

Reviewed-by: Boris Ostrovsky <boris.ostrovsky@xxxxxxxxxx>

I think it does not:

drivers/xen/pci.c: In function âxen_mcfg_lateâ:
drivers/xen/pci.c:221:18: error: âpci_mmcfg_listâ undeclared (first
use in this function)
drivers/xen/pci.c:221:18: note: each undeclared identifier is reported
only once for each f

Right, we need:
+#include <linux/ecam.h>

Will fix this in next version, thanks!

Hmm, I think we just missed the head file, but the logic
of this patch is still right.



Yes, removing the test should be safe.

-boris

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