queue-4.19/pci-designware-ep-use-aligned-atu-window-for-raising.patch

   1 From faf9b1cbbc6a7f67a102be827a55e6789deb7553 Mon Sep 17 00:00:00 2001
   2 From: Kishon Vijay Abraham I <kishon@ti.com>
   3 Date: Mon, 25 Mar 2019 15:09:45 +0530
   4 Subject: PCI: designware-ep: Use aligned ATU window for raising MSI interrupts
   5
   6 [ Upstream commit 6b7330303a8186fb211357e6d379237fe9d2ece1 ]
   7
   8 Certain platforms like K2G reguires the outbound ATU window to be
   9 aligned. The alignment size is already present in mem->page_size.
  10 Use the alignment size present in mem->page_size to configure an
  11 aligned ATU window. In order to raise an interrupt, CPU has to write
  12 to address offset from the start of the window unlike before where
  13 writes were always to the beginning of the ATU window.
  14
  15 Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
  16 Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
  17 Signed-off-by: Sasha Levin <sashal@kernel.org>
  18 ---
  19  drivers/pci/controller/dwc/pcie-designware-ep.c | 7 +++++--
  20  1 file changed, 5 insertions(+), 2 deletions(-)
  21
  22 diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c
  23 index de8635af4cde..739d97080d3b 100644
  24 --- a/drivers/pci/controller/dwc/pcie-designware-ep.c
  25 +++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
  26 @@ -385,6 +385,7 @@ int dw_pcie_ep_raise_msi_irq(struct dw_pcie_ep *ep, u8 func_no,
  27  {
  28         struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
  29         struct pci_epc *epc = ep->epc;
  30 +       unsigned int aligned_offset;
  31         u16 msg_ctrl, msg_data;
  32         u32 msg_addr_lower, msg_addr_upper, reg;
  33         u64 msg_addr;
  34 @@ -410,13 +411,15 @@ int dw_pcie_ep_raise_msi_irq(struct dw_pcie_ep *ep, u8 func_no,
  35                 reg = ep->msi_cap + PCI_MSI_DATA_32;
  36                 msg_data = dw_pcie_readw_dbi(pci, reg);
  37         }
  38 -       msg_addr = ((u64) msg_addr_upper) << 32 | msg_addr_lower;
  39 +       aligned_offset = msg_addr_lower & (epc->mem->page_size - 1);
  40 +       msg_addr = ((u64)msg_addr_upper) << 32 |
  41 +                       (msg_addr_lower & ~aligned_offset);
  42         ret = dw_pcie_ep_map_addr(epc, func_no, ep->msi_mem_phys, msg_addr,
  43                                   epc->mem->page_size);
  44         if (ret)
  45                 return ret;
  46
  47 -       writel(msg_data | (interrupt_num - 1), ep->msi_mem);
  48 +       writel(msg_data | (interrupt_num - 1), ep->msi_mem + aligned_offset);
  49
  50         dw_pcie_ep_unmap_addr(epc, func_no, ep->msi_mem_phys);
  51
  52 --
  53 2.20.1
  54