From f3a296405b6e65fe478144c2f85602dc5668700c Mon Sep 17 00:00:00 2001 From: Ajay Agarwal Date: Wed, 21 Feb 2024 21:08:40 +0530 Subject: PCI: dwc: Strengthen the MSI address allocation logic MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit There can be platforms that do not use/have 32-bit DMA addresses. The current implementation of 32-bit IOVA allocation can fail for such platforms, eventually leading to the probe failure. Try to allocate a 32-bit msi_data. If this allocation fails, attempt a 64-bit address allocation. Please note that if the 64-bit MSI address is allocated, then the EPs supporting 32-bit MSI address only will not work. Link: https://lore.kernel.org/linux-pci/20240221153840.1789979-1-ajayagarwal@google.com Tested-by: Will McVicker Signed-off-by: Ajay Agarwal Signed-off-by: Krzysztof Wilczyński Reviewed-by: Manivannan Sadhasivam Reviewed-by: Serge Semin Reviewed-by: Will McVicker --- drivers/pci/controller/dwc/pcie-designware-host.c | 21 +++++++++++++-------- 1 file changed, 13 insertions(+), 8 deletions(-) (limited to 'drivers/pci/controller') diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c index d5fc31f8345f..d15a5c2d5b48 100644 --- a/drivers/pci/controller/dwc/pcie-designware-host.c +++ b/drivers/pci/controller/dwc/pcie-designware-host.c @@ -328,7 +328,7 @@ static int dw_pcie_msi_host_init(struct dw_pcie_rp *pp) struct dw_pcie *pci = to_dw_pcie_from_pp(pp); struct device *dev = pci->dev; struct platform_device *pdev = to_platform_device(dev); - u64 *msi_vaddr; + u64 *msi_vaddr = NULL; int ret; u32 ctrl, num_ctrls; @@ -379,15 +379,20 @@ static int dw_pcie_msi_host_init(struct dw_pcie_rp *pp) * memory. */ ret = dma_set_coherent_mask(dev, DMA_BIT_MASK(32)); - if (ret) - dev_warn(dev, "Failed to set DMA mask to 32-bit. Devices with only 32-bit MSI support may not work properly\n"); + if (!ret) + msi_vaddr = dmam_alloc_coherent(dev, sizeof(u64), &pp->msi_data, + GFP_KERNEL); - msi_vaddr = dmam_alloc_coherent(dev, sizeof(u64), &pp->msi_data, - GFP_KERNEL); if (!msi_vaddr) { - dev_err(dev, "Failed to alloc and map MSI data\n"); - dw_pcie_free_msi(pp); - return -ENOMEM; + dev_warn(dev, "Failed to allocate 32-bit MSI address\n"); + dma_set_coherent_mask(dev, DMA_BIT_MASK(64)); + msi_vaddr = dmam_alloc_coherent(dev, sizeof(u64), &pp->msi_data, + GFP_KERNEL); + if (!msi_vaddr) { + dev_err(dev, "Failed to allocate MSI address\n"); + dw_pcie_free_msi(pp); + return -ENOMEM; + } } return 0; -- cgit v1.2.3