Re: [RFC] pciehp: Add archdata setting

[Hiroo Matsumoto <matsumoto.hiroo@jp.fujitsu.com>]

[-- Attachment #1: Type: text/plain, Size: 1316 bytes --]

Hi, Bjorn


I wrote a code with bus_register_notifier().
A function that calls bus_register_notifer() is called from 
rootfs_initcall as well as amd_iommu is.

Please review this.


Regards.

Hiroo MATSUMOTO

> Hi, Bjorn
> 
> 
> Thanks for your research and comment.
> 
> As you said, a way of registering code with bus_register_notifier(), 
> which will be called in device_add(), is better one than 
> pcibios_enable_device().
> I will try to write code with bus_register_notifier().
> 
> 
> Regards.
> 
> Hiroo MATSUMOTO
> 
>> On Wed, Apr 11, 2012 at 11:00 PM, Hiroo Matsumoto
>> <matsumoto.hiroo@jp.fujitsu.com> wrote:
>>> Hi, Kaneshige
>>>
>>>
>>> You are right!
>>> Setting dma_ops in pcibios_enable_device is a nice way.
>>> In PCI driver, pci_enable_device_xxx that calls pcibios_enable_device is
>>> called before checking archdata.dma_ops.
>>>
>>> I added code of checking and setting dma_ops to pcibios_enable_device in
>>> arch/powerpc/kernel/pci-common.c.
>>> It works good.
>>
>> When I researched this, I thought the best route was to use the
>> bus_register_notifier() path, as amd_iommu_init_notifier() does.
>>
>> We're filling in a struct device field, not a PCI field, and
>> bus_register_notifier() seems like a more generic path than relying on
>> pcibios_enable_device().
>>
>> Bjorn
>>
>>
> 

[-- Attachment #2: ppc-pcibios-bus_notifier-for-hp.patch --]
[-- Type: text/plain, Size: 2136 bytes --]

Signed-off-by: Hiroo MATSUMOTO <matsumoto.hiroo@jp.fujitsu.com>
diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c
index 32656f1..1fe1e25 100644
--- a/arch/powerpc/kernel/pci-common.c
+++ b/arch/powerpc/kernel/pci-common.c
@@ -1083,6 +1083,17 @@ void __devinit pcibios_setup_bus_self(struct pci_bus *bus)
 		ppc_md.pci_dma_bus_setup(bus);
 }
 
+static inline void pcibios_set_dma_ops(struct pci_dev *dev)
+{
+	/* Hook up default DMA ops */
+	set_dma_ops(&dev->dev, pci_dma_ops);
+	set_dma_offset(&dev->dev, PCI_DRAM_OFFSET);
+
+	/* Additional platform DMA/iommu setup */
+	if (ppc_md.pci_dma_dev_setup)
+		ppc_md.pci_dma_dev_setup(dev);
+}
+
 void __devinit pcibios_setup_bus_devices(struct pci_bus *bus)
 {
 	struct pci_dev *dev;
@@ -1102,13 +1113,7 @@ void __devinit pcibios_setup_bus_devices(struct pci_bus *bus)
 		 */
 		set_dev_node(&dev->dev, pcibus_to_node(dev->bus));
 
-		/* Hook up default DMA ops */
-		set_dma_ops(&dev->dev, pci_dma_ops);
-		set_dma_offset(&dev->dev, PCI_DRAM_OFFSET);
-
-		/* Additional platform DMA/iommu setup */
-		if (ppc_md.pci_dma_dev_setup)
-			ppc_md.pci_dma_dev_setup(dev);
+		pcibios_set_dma_ops(dev);
 
 		/* Read default IRQs and fixup if necessary */
 		pci_read_irq_line(dev);
@@ -1749,3 +1754,33 @@ static void fixup_hide_host_resource_fsl(struct pci_dev *dev)
 }
 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_MOTOROLA, PCI_ANY_ID, fixup_hide_host_resource_fsl);
 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_FREESCALE, PCI_ANY_ID, fixup_hide_host_resource_fsl);
+
+static int pcibios_device_change_notifier(struct notifier_block *nb,
+					  unsigned long action, void *data)
+{
+	struct pci_dev *dev = to_pci_dev(data);
+
+	if (!dev)
+		return 0;
+
+	switch (action) {
+	case BUS_NOTIFY_ADD_DEVICE:
+		if (!get_dma_ops(&dev->dev))
+			pcibios_set_dma_ops(dev);
+		break;
+	default:
+		break;
+	}
+
+	return 0;
+}
+
+static struct notifier_block device_nb = {
+	.notifier_call = pcibios_device_change_notifier,
+};
+
+static int pcibios_bus_notifier_init(void)
+{
+	return bus_register_notifier(&pci_bus_type, &device_nb);
+}
+rootfs_initcall(pcibios_bus_notifier_init);