| Message ID | 1421800225-26230-24-git-send-email-wangyijing@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Dear Yijing Wang, On Wed, 21 Jan 2015 08:30:18 +0800, Yijing Wang wrote: > Mvebu_pcie_scan_bus() is not necessary, we could use > pci_common_init_dev() instead of pci_common_init(), > and pass the device pointer as the parent. Then > pci_scan_root_bus() will be called to scan the pci busses. > > Signed-off-by: Yijing Wang <wangyijing@huawei.com> > CC: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> > CC: Jason Cooper <jason@lakedaemon.net> While I'm fine with the change to pci_common_init_dev(), I am not so sure about the removal of mvebu_pcie_scan_bus(). I vaguely remember that we intentionally did not use the default function for a specific reason. Of course, this was a long time ago, and I don't remember the reason. I would have to take a bit of time to 1/ review the archives of the discussion surrounding the pcie-mvebu driver, and 2/ test your patch to validate it works fine on HW. Thanks! Thomas
On 2015/1/23 1:40, Thomas Petazzoni wrote: > Dear Yijing Wang, > > On Wed, 21 Jan 2015 08:30:18 +0800, Yijing Wang wrote: >> Mvebu_pcie_scan_bus() is not necessary, we could use >> pci_common_init_dev() instead of pci_common_init(), >> and pass the device pointer as the parent. Then >> pci_scan_root_bus() will be called to scan the pci busses. >> >> Signed-off-by: Yijing Wang <wangyijing@huawei.com> >> CC: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> >> CC: Jason Cooper <jason@lakedaemon.net> > > While I'm fine with the change to pci_common_init_dev(), I am not so > sure about the removal of mvebu_pcie_scan_bus(). I vaguely remember > that we intentionally did not use the default function for a specific > reason. Of course, this was a long time ago, and I don't remember the > reason. I would have to take a bit of time to 1/ review the archives of > the discussion surrounding the pcie-mvebu driver, and 2/ test your > patch to validate it works fine on HW. Hi Thomas, Thanks for your comments and help to test :) > > Thanks! > > Thomas >
Hi Thomas, On Thu, Jan 22, 2015 at 05:40:00PM +0000, Thomas Petazzoni wrote: > Dear Yijing Wang, > > On Wed, 21 Jan 2015 08:30:18 +0800, Yijing Wang wrote: > > Mvebu_pcie_scan_bus() is not necessary, we could use > > pci_common_init_dev() instead of pci_common_init(), > > and pass the device pointer as the parent. Then > > pci_scan_root_bus() will be called to scan the pci busses. > > > > Signed-off-by: Yijing Wang <wangyijing@huawei.com> > > CC: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> > > CC: Jason Cooper <jason@lakedaemon.net> > > While I'm fine with the change to pci_common_init_dev(), I am not so > sure about the removal of mvebu_pcie_scan_bus(). I vaguely remember > that we intentionally did not use the default function for a specific > reason. Of course, this was a long time ago, and I don't remember the > reason. I would have to take a bit of time to 1/ review the archives of > the discussion surrounding the pcie-mvebu driver, and 2/ test your > patch to validate it works fine on HW. I guess the reason: by providing the scan pointer to pcibios through the hw_pci struct you were preventing calling pci_scan_root_bus() in bios32.c that in turn can add devices before the resources are assigned. Basically mvebu_pci_scan_bus() was doing what pci_scan_root_bus() does except for calling pci_bus_add_devices(). Yijing patches remove pci_bus_add_devices() from pci_scan_root_bus() so his change should be fine and it actually improves the current behaviour which is quite hard to untangle, and not just on mvebu (I suspect drivers/pci/host/pcie-xilinx.c can suffer from the same problem). Lorenzo > > Thanks! > > Thomas > -- > Thomas Petazzoni, CTO, Free Electrons > Embedded Linux, Kernel and Android engineering > http://free-electrons.com > -- > To unsubscribe from this list: send the line "unsubscribe linux-pci" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >
diff --git a/drivers/pci/host/pci-mvebu.c b/drivers/pci/host/pci-mvebu.c index 1309cfb..d5a2b70 100644 --- a/drivers/pci/host/pci-mvebu.c +++ b/drivers/pci/host/pci-mvebu.c @@ -750,21 +750,6 @@ static int mvebu_pcie_setup(int nr, struct pci_sys_data *sys) return 1; } -static struct pci_bus *mvebu_pcie_scan_bus(int nr, struct pci_sys_data *sys) -{ - struct mvebu_pcie *pcie = sys_to_pcie(sys); - struct pci_bus *bus; - - bus = pci_create_root_bus(&pcie->pdev->dev, sys->busnr, - &mvebu_pcie_ops, sys, &sys->resources); - if (!bus) - return NULL; - - pci_scan_child_bus(bus); - - return bus; -} - static resource_size_t mvebu_pcie_align_resource(struct pci_dev *dev, const struct resource *res, resource_size_t start, @@ -808,12 +793,11 @@ static void mvebu_pcie_enable(struct mvebu_pcie *pcie) hw.nr_controllers = 1; hw.private_data = (void **)&pcie; hw.setup = mvebu_pcie_setup; - hw.scan = mvebu_pcie_scan_bus; hw.map_irq = of_irq_parse_and_map_pci; hw.ops = &mvebu_pcie_ops; hw.align_resource = mvebu_pcie_align_resource; - pci_common_init(&hw); + pci_common_init_dev(&pcie->pdev->dev, &hw); } /*
Mvebu_pcie_scan_bus() is not necessary, we could use pci_common_init_dev() instead of pci_common_init(), and pass the device pointer as the parent. Then pci_scan_root_bus() will be called to scan the pci busses. Signed-off-by: Yijing Wang <wangyijing@huawei.com> CC: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> CC: Jason Cooper <jason@lakedaemon.net> --- drivers/pci/host/pci-mvebu.c | 18 +----------------- 1 files changed, 1 insertions(+), 17 deletions(-)