Re: [PATCH] PCI: dra7xx: program outbound atu with correct address

From: Bjorn Helgaas
Date: Tue May 03 2016 - 12:51:09 EST


On Mon, May 02, 2016 at 04:09:33PM -0500, Bjorn Helgaas wrote:
> On Mon, May 02, 2016 at 04:54:40PM +0200, Niklas Cassel wrote:
> > From: Niklas Cassel <niklas.cassel@xxxxxxxx>
> >
> > commit 1488aefa37a4 ("PCI: designware: Move Root Complex
> > setup code to dw_pcie_setup_rc()") broke dra7xx
> > by moving code from dw_pcie_host_init to dw_pcie_setup_rc.
> >
> > Fix this by doing the cpu to bus calculation before calling
> > dw_pcie_setup_rc.
> >
> > Fixes: 1488aefa37a4 ("PCI: designware: Move Root Complex setup code to dw_pcie_setup_rc()")
> > Signed-off-by: Niklas Cassel <niklas.cassel@xxxxxxxx>
> > ---
> > drivers/pci/host/pci-dra7xx.c | 4 ++--
> > 1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/pci/host/pci-dra7xx.c b/drivers/pci/host/pci-dra7xx.c
> > index 2ca3a1f..f441130 100644
> > --- a/drivers/pci/host/pci-dra7xx.c
> > +++ b/drivers/pci/host/pci-dra7xx.c
> > @@ -142,13 +142,13 @@ static void dra7xx_pcie_enable_interrupts(struct pcie_port *pp)
> >
> > static void dra7xx_pcie_host_init(struct pcie_port *pp)
> > {
> > - dw_pcie_setup_rc(pp);
> > -
> > pp->io_base &= DRA7XX_CPU_TO_BUS_ADDR;
> > pp->mem_base &= DRA7XX_CPU_TO_BUS_ADDR;
> > pp->cfg0_base &= DRA7XX_CPU_TO_BUS_ADDR;
> > pp->cfg1_base &= DRA7XX_CPU_TO_BUS_ADDR;
> >
> > + dw_pcie_setup_rc(pp);
>
> This looks correct to me. Prior to 1488aefa37a4, we had this path,
> which applied the dra7xx mem_base adjustment before programming the
> outbound ATU:
>
> dra7xx_add_pcie_port
> dw_pcie_host_init
> pp->mem_base = pp->mem->start # <-- set pp->mem_base
> ops->host_init
> dra7xx_pcie_host_init # .host_init
> dw_pcie_setup_rc
> pp->mem_base &= DRA7XX_CPU_TO_BUS_ADDR # <-- update pp->mem_base
> dw_pcie_prog_outbound_atu(pp->mem_base) # <-- use pp->mem_base
>
> After 1488aefa37a4, we have this:
>
> dra7xx_add_pcie_port
> dw_pcie_host_init
> pp->mem_base = pp->mem->start # <-- set pp->mem_base
> ops->host_init
> dra7xx_pcie_host_init # .host_init
> dw_pcie_setup_rc
> dw_pcie_prog_outbound_atu(pp->mem_base) # <-- use pp->mem_base
> pp->mem_base &= DRA7XX_CPU_TO_BUS_ADDR # <-- update pp->mem_base
>
> So the dra7xx update is applied after we've already used it.
>
> If you agree, Kishon, I'll fold Niklas's fix into Jisheng's patch so
> there's no bisection hole for dra7xx.

I merged this (folded into Jisheng's patch on the pci/host-designware
branch, and included in my "next" branch).

Please let me know if it works for you, Niklas, or if you see any
problems.

> > dra7xx_pcie_establish_link(pp);
> > if (IS_ENABLED(CONFIG_PCI_MSI))
> > dw_pcie_msi_init(pp);
> > --
> > 2.1.4
> >
> > --
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