From: Vidya Sagar Date: Mon, 19 Sep 2022 14:33:40 +0000 (+0530) Subject: PCI: designware-ep: Disable PTM capabilities for EP mode X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=442ae919e6ca77354551a7b8717746b44272e274;p=linux.git PCI: designware-ep: Disable PTM capabilities for EP mode Dual mode DesignWare PCIe IP has PTM capability enabled (if supported) even in the EP mode. The PCIe compliance for the EP mode expects PTM capabilities (ROOT_CAPABLE, RES_CAPABLE, CLK_GRAN) be disabled. Hence disable PTM for the EP mode. Link: https://lore.kernel.org/r/20220919143340.4527-3-vidyas@nvidia.com Signed-off-by: Vidya Sagar Signed-off-by: Lorenzo Pieralisi Acked-by: Jingoo Han --- diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c index 83ddb190292e4..efc6c6360e28f 100644 --- a/drivers/pci/controller/dwc/pcie-designware-ep.c +++ b/drivers/pci/controller/dwc/pcie-designware-ep.c @@ -643,7 +643,7 @@ static unsigned int dw_pcie_ep_find_ext_capability(struct dw_pcie *pci, int cap) int dw_pcie_ep_init_complete(struct dw_pcie_ep *ep) { struct dw_pcie *pci = to_dw_pcie_from_ep(ep); - unsigned int offset; + unsigned int offset, ptm_cap_base; unsigned int nbars; u8 hdr_type; u32 reg; @@ -659,6 +659,7 @@ int dw_pcie_ep_init_complete(struct dw_pcie_ep *ep) } offset = dw_pcie_ep_find_ext_capability(pci, PCI_EXT_CAP_ID_REBAR); + ptm_cap_base = dw_pcie_ep_find_ext_capability(pci, PCI_EXT_CAP_ID_PTM); dw_pcie_dbi_ro_wr_en(pci); @@ -671,6 +672,22 @@ int dw_pcie_ep_init_complete(struct dw_pcie_ep *ep) dw_pcie_writel_dbi(pci, offset + PCI_REBAR_CAP, 0x0); } + /* + * PTM responder capability can be disabled only after disabling + * PTM root capability. + */ + if (ptm_cap_base) { + dw_pcie_dbi_ro_wr_en(pci); + reg = dw_pcie_readl_dbi(pci, ptm_cap_base + PCI_PTM_CAP); + reg &= ~PCI_PTM_CAP_ROOT; + dw_pcie_writel_dbi(pci, ptm_cap_base + PCI_PTM_CAP, reg); + + reg = dw_pcie_readl_dbi(pci, ptm_cap_base + PCI_PTM_CAP); + reg &= ~(PCI_PTM_CAP_RES | PCI_PTM_GRANULARITY_MASK); + dw_pcie_writel_dbi(pci, ptm_cap_base + PCI_PTM_CAP, reg); + dw_pcie_dbi_ro_wr_dis(pci); + } + dw_pcie_setup(pci); dw_pcie_dbi_ro_wr_dis(pci);