@@ -83,10 +83,19 @@ irqreturn_t dw_handle_msi_irq(struct pcie_port *pp)
void dw_pcie_msi_init(struct pcie_port *pp)
{
+ struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
+ struct device *dev = pci->dev;
+ struct page *page;
u64 msi_target;
- pp->msi_data = __get_free_pages(GFP_KERNEL, 0);
- msi_target = virt_to_phys((void *)pp->msi_data);
+ page = alloc_page(GFP_KERNEL | GFP_DMA32);
+ pp->msi_data = dma_map_page(dev, page, 0, PAGE_SIZE, DMA_FROM_DEVICE);
+ if (dma_mapping_error(dev, pp->msi_data)) {
+ dev_err(dev, "failed to map MSI data\n");
+ __free_page(page);
+ return;
+ }
+ msi_target = (u64)pp->msi_data;
/* program the msi_data */
dw_pcie_wr_own_conf(pp, PCIE_MSI_ADDR_LO, 4,
@@ -187,7 +196,7 @@ static void dw_msi_setup_msg(struct pcie_port *pp, unsigned int irq, u32 pos)
if (pp->ops->get_msi_addr)
msi_target = pp->ops->get_msi_addr(pp);
else
- msi_target = virt_to_phys((void *)pp->msi_data);
+ msi_target = (u64)pp->msi_data;
msg.address_lo = (u32)(msi_target & 0xffffffff);
msg.address_hi = (u32)(msi_target >> 32 & 0xffffffff);
@@ -14,6 +14,7 @@
#ifndef _PCIE_DESIGNWARE_H
#define _PCIE_DESIGNWARE_H
+#include <linux/dma-mapping.h>
#include <linux/irq.h>
#include <linux/msi.h>
#include <linux/pci.h>
@@ -168,7 +169,7 @@ struct pcie_port {
const struct dw_pcie_host_ops *ops;
int msi_irq;
struct irq_domain *irq_domain;
- unsigned long msi_data;
+ dma_addr_t msi_data;
DECLARE_BITMAP(msi_irq_in_use, MAX_MSI_IRQS);
};
Since it is a PCIe endpoint device, rather than the CPU, that is supposed to write to this location, the proper way to get the address to this this location is really to use the DMA API, rather than virt_to_phys. Using virt_to_phys might work on some systems, but by using the DMA API, we know that it will work on all systems. This is essentially the same thing as allocating a buffer in a driver, to which the endpoint will write to. To do this, we use the DMA API. Signed-off-by: Niklas Cassel <niklas.cassel@axis.com> --- V2: * Sort headers. * MSI with captial letters in error print. * Don't change to lower_32_bits/upper_32_bits, since that should in that case be its own patch. drivers/pci/dwc/pcie-designware-host.c | 15 ++++++++++++--- drivers/pci/dwc/pcie-designware.h | 3 ++- 2 files changed, 14 insertions(+), 4 deletions(-)