Am Dienstag, den 16.09.2014, 09:30 +0800 schrieb Yijing Wang: > On 2014/9/15 22:00, Lucas Stach wrote: > > Am Freitag, den 05.09.2014, 18:09 +0800 schrieb Yijing Wang: > >> Currently, pcie-designware, pcie-rcar, pci-tegra drivers > >> use irq chip_data to save the msi_chip pointer. They > >> already call irq_set_chip_data() in their own MSI irq map > >> functions. So irq_set_chip_data() in arch_setup_msi_irq() > >> is useless. > >> > >> Signed-off-by: Yijing Wang <wangyijing@xxxxxxxxxx> > >> --- > >> drivers/pci/msi.c | 2 -- > >> 1 files changed, 0 insertions(+), 2 deletions(-) > >> > >> diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c > >> index f6cb317..d547f7f 100644 > >> --- a/drivers/pci/msi.c > >> +++ b/drivers/pci/msi.c > >> @@ -41,8 +41,6 @@ int __weak arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc) > >> if (err < 0) > >> return err; > >> > >> - irq_set_chip_data(desc->irq, chip); > >> - > >> return 0; > >> } > >> > > > > arch_teardown_msi_irq() expects to find the msi_chip in the irq > > chip_data field. As this means drivers don't have any reasonable other > > possibility to stuff things into this field, I think it would make sense > > to do the cleanup the other way around: keep the irq_set_chip_data > > arch_setup_msi_irq() and rip it out of the individual drivers. > > Hi Lucas, thanks for your review and comments! > irq_set_chip_data() should not be placed in MSI core functions, because other arch like x86, > use irq_data->chip_data to stores irq_cfg. So how to set the chip_data is arch dependent. > And this series is mainly to use MSI chip framework in all platforms. > Currently, only ARM platform MSI drivers use the chip_data to store msi_chip, and the drivers call > irq_set_chip_data() in their driver already. So I thought we should clean up it in MSI core code. > Okay I see your point, so the cleanup done this way is okay. But then this still introduces a problem: arch_teardown_msi_irq() expects to find the msi_chip in the chip_data field, which is okay for all ARM PCI host drivers, but not for other arch MSI chips. You fix this by completely removing arch_teardown_msi_irq() at the end of the series, but this still has the potential to introduce issues for other arches than ARM within the series. So this patch should include a change to replace the line struct msi_chip *chip = irq_get_chip_data(irq); with something that doesn't rely on the msi_chip being in the irq chip_data field. Regards, Lucas -- Pengutronix e.K. | Lucas Stach | Industrial Linux Solutions | http://www.pengutronix.de/ |
