On Tue, Apr 20, 2021 at 02:05:26PM +0100, Marc Zyngier wrote:
> When going into suspend, the Tegra MSI controller loses its
> state. Restore the MSI allocation on resume so that PCI devices
> are usable again.
>
> Reported-by: Jon Hunter <jonath...@nvidia.com>
> Tested-by: Jon Hunter <jonath...@nvidia.com>
> Fixes: 973a28677e39 ("PCI: tegra: Convert to MSI domains")
> Signed-off-by: Marc Zyngier <m...@kernel.org>
> Cc: Lorenzo Pieralisi <lorenzo.pieral...@arm.com>
> Cc: Bjorn Helgaas <bhelg...@google.com>
> Cc: Thierry Reding <thierry.red...@gmail.com>
> ---
> drivers/pci/controller/pci-tegra.c | 8 +++++++-
> 1 file changed, 7 insertions(+), 1 deletion(-)
Squashed with the Fixes: commit, updated my pci/msi branch with it
and pushed out.
Thanks,
Lorenzo
> diff --git a/drivers/pci/controller/pci-tegra.c
> b/drivers/pci/controller/pci-tegra.c
> index eaba7b2fab4a..507b23d43ad1 100644
> --- a/drivers/pci/controller/pci-tegra.c
> +++ b/drivers/pci/controller/pci-tegra.c
> @@ -1802,13 +1802,19 @@ static void tegra_pcie_enable_msi(struct tegra_pcie
> *pcie)
> {
> const struct tegra_pcie_soc *soc = pcie->soc;
> struct tegra_msi *msi = &pcie->msi;
> - u32 reg;
> + u32 reg, msi_state[INT_PCI_MSI_NR / 32];
> + int i;
>
> afi_writel(pcie, msi->phys >> soc->msi_base_shift, AFI_MSI_FPCI_BAR_ST);
> afi_writel(pcie, msi->phys, AFI_MSI_AXI_BAR_ST);
> /* this register is in 4K increments */
> afi_writel(pcie, 1, AFI_MSI_BAR_SZ);
>
> + /* Restore the MSI allocation state */
> + bitmap_to_arr32(msi_state, msi->used, INT_PCI_MSI_NR);
> + for (i = 0; i < ARRAY_SIZE(msi_state); i++)
> + afi_writel(pcie, msi_state[i], AFI_MSI_EN_VEC(i));
> +
> /* and unmask the MSI interrupt */
> reg = afi_readl(pcie, AFI_INTR_MASK);
> reg |= AFI_INTR_MASK_MSI_MASK;
> --
> 2.30.2
>
