From 4fb8e46c1bc4ee16d8b4ec53933b2ed46e31e158 Mon Sep 17 00:00:00 2001 From: Vidya Sagar Date: Thu, 21 Jul 2022 19:50:48 +0530 Subject: PCI: tegra194: Enable support for 256 Byte payload Set 256 byte payload as the default in the Device Control Register to allow the PCIe subsystem to enable 256 byte Max Payload Size when a capable link partner is connected. Link: https://lore.kernel.org/r/20220721142052.25971-13-vidyas@nvidia.com Signed-off-by: Vidya Sagar Signed-off-by: Bjorn Helgaas --- drivers/pci/controller/dwc/pcie-tegra194.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 'drivers/pci/controller/dwc') diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/controller/dwc/pcie-tegra194.c index 5f1798d37572..f82c70be72ef 100644 --- a/drivers/pci/controller/dwc/pcie-tegra194.c +++ b/drivers/pci/controller/dwc/pcie-tegra194.c @@ -839,6 +839,7 @@ static int tegra_pcie_dw_host_init(struct pcie_port *pp) struct dw_pcie *pci = to_dw_pcie_from_pp(pp); struct tegra_pcie_dw *pcie = to_tegra_pcie(pci); u32 val; + u16 val_16; pp->bridge->ops = &tegra_pci_ops; @@ -846,6 +847,11 @@ static int tegra_pcie_dw_host_init(struct pcie_port *pp) pcie->pcie_cap_base = dw_pcie_find_capability(&pcie->pci, PCI_CAP_ID_EXP); + val_16 = dw_pcie_readw_dbi(pci, pcie->pcie_cap_base + PCI_EXP_DEVCTL); + val_16 &= ~PCI_EXP_DEVCTL_PAYLOAD; + val_16 |= PCI_EXP_DEVCTL_PAYLOAD_256B; + dw_pcie_writew_dbi(pci, pcie->pcie_cap_base + PCI_EXP_DEVCTL, val_16); + val = dw_pcie_readl_dbi(pci, PCI_IO_BASE); val &= ~(IO_BASE_IO_DECODE | IO_BASE_IO_DECODE_BIT8); dw_pcie_writel_dbi(pci, PCI_IO_BASE, val); @@ -1632,6 +1638,7 @@ static void pex_ep_event_pex_rst_deassert(struct tegra_pcie_dw *pcie) struct device *dev = pcie->dev; u32 val; int ret; + u16 val_16; if (pcie->ep_state == EP_STATE_ENABLED) return; @@ -1749,6 +1756,12 @@ static void pex_ep_event_pex_rst_deassert(struct tegra_pcie_dw *pcie) pcie->pcie_cap_base = dw_pcie_find_capability(&pcie->pci, PCI_CAP_ID_EXP); + + val_16 = dw_pcie_readw_dbi(pci, pcie->pcie_cap_base + PCI_EXP_DEVCTL); + val_16 &= ~PCI_EXP_DEVCTL_PAYLOAD; + val_16 |= PCI_EXP_DEVCTL_PAYLOAD_256B; + dw_pcie_writew_dbi(pci, pcie->pcie_cap_base + PCI_EXP_DEVCTL, val_16); + clk_set_rate(pcie->core_clk, GEN4_CORE_CLK_FREQ); val = (ep->msi_mem_phys & MSIX_ADDR_MATCH_LOW_OFF_MASK); -- cgit v1.2.3