From 423511ec23e2a6fa7830ed76b0283268e795d09d Mon Sep 17 00:00:00 2001 From: Will McVicker Date: Thu, 25 Aug 2022 23:54:02 +0000 Subject: [PATCH] PCI: dwc: Drop dependency on ZONE_DMA32 Re-work the msi_msg DMA allocation logic to use dmam_alloc_coherent() which uses the coherent DMA mask to try to return an allocation within the DMA mask limits. With that, we now can drop the msi_page parameter in struct dw_pcie_rp. This allows kernel configurations that disable ZONE_DMA32 to continue supporting a 32-bit DMA mask. Without this patch, the PCIe host device will fail to probe when ZONE_DMA32 is disabled. Link: https://lore.kernel.org/r/20220825235404.4132818-2-willmcvicker@google.com Fixes: 35797e672ff0 ("PCI: dwc: Fix MSI msi_msg DMA mapping") Reported-by: Isaac J. Manjarres Signed-off-by: Will McVicker Signed-off-by: Lorenzo Pieralisi Reviewed-by: Rob Herring Acked-by: Jingoo Han --- drivers/pci/controller/dwc/pcie-designware-host.c | 28 ++++++----------------- drivers/pci/controller/dwc/pcie-designware.h | 1 - 2 files changed, 7 insertions(+), 22 deletions(-) diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c index 7746f94..39f3b37 100644 --- a/drivers/pci/controller/dwc/pcie-designware-host.c +++ b/drivers/pci/controller/dwc/pcie-designware-host.c @@ -267,15 +267,6 @@ static void dw_pcie_free_msi(struct dw_pcie_rp *pp) irq_domain_remove(pp->msi_domain); irq_domain_remove(pp->irq_domain); - - if (pp->msi_data) { - struct dw_pcie *pci = to_dw_pcie_from_pp(pp); - struct device *dev = pci->dev; - - dma_unmap_page(dev, pp->msi_data, PAGE_SIZE, DMA_FROM_DEVICE); - if (pp->msi_page) - __free_page(pp->msi_page); - } } static void dw_pcie_msi_init(struct dw_pcie_rp *pp) @@ -336,6 +327,7 @@ 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; int ret; u32 ctrl, num_ctrls; @@ -375,22 +367,16 @@ static int dw_pcie_msi_host_init(struct dw_pcie_rp *pp) dw_chained_msi_isr, pp); } - ret = dma_set_mask(dev, DMA_BIT_MASK(32)); + ret = dma_set_mask_and_coherent(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"); - pp->msi_page = alloc_page(GFP_DMA32); - pp->msi_data = dma_map_page(dev, pp->msi_page, 0, - PAGE_SIZE, DMA_FROM_DEVICE); - ret = dma_mapping_error(dev, pp->msi_data); - if (ret) { - dev_err(pci->dev, "Failed to map MSI data\n"); - __free_page(pp->msi_page); - pp->msi_page = NULL; - pp->msi_data = 0; + 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 ret; + return -ENOMEM; } return 0; diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h index 09b8870..a871ae7 100644 --- a/drivers/pci/controller/dwc/pcie-designware.h +++ b/drivers/pci/controller/dwc/pcie-designware.h @@ -243,7 +243,6 @@ struct dw_pcie_rp { struct irq_domain *irq_domain; struct irq_domain *msi_domain; dma_addr_t msi_data; - struct page *msi_page; struct irq_chip *msi_irq_chip; u32 num_vectors; u32 irq_mask[MAX_MSI_CTRLS]; -- 2.7.4