dw_pcie_prog_ep_inbound_atu() is used to program an inbound iATU in
"BAR Match Mode".
A memory address returned by e.g. kmalloc() is guaranteed to have natural
alignment (aligned to the size of the allocation). It is however not
guaranteed that pci_epc_set_bar() (and thus dw_pcie_prog_ep_inbound_atu())
is supplied an address that has natural alignment. (An EPF driver can send
in an arbitrary physical address to pci_epc_set_bar().)
The DWC Databook description for the LWR_TARGET_RW and LWR_TARGET_HW fields
in the IATU_LWR_TARGET_ADDR_OFF_INBOUND_i registers state that:
"Field size depends on log2(BAR_MASK+1) in BAR match mode."
I.e. only the upper bits are writable, and the number of writable bits is
dependent on the configured BAR_MASK.
Add a check to ensure that the physical address programmed in the iATU is
aligned to the size of the BAR (BAR_MASK+1), as without this, we can get
hard to debug errors, as we could write to bits that are read-only (without
getting a write error), which could cause the iATU to end up redirecting to
a physical address that is different from the address that we intended.
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
Signed-off-by: Niklas Cassel <cassel@xxxxxxxxxx>
---
drivers/pci/controller/dwc/pcie-designware-ep.c | 8 +++++---
drivers/pci/controller/dwc/pcie-designware.c | 5 +++--
drivers/pci/controller/dwc/pcie-designware.h | 2 +-
3 files changed, 9 insertions(+), 6 deletions(-)
diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c
index 44a617d54b15..8e07d432e74f 100644
--- a/drivers/pci/controller/dwc/pcie-designware-ep.c
+++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
@@ -128,7 +128,8 @@ static int dw_pcie_ep_write_header(struct pci_epc *epc, u8 func_no, u8 vfunc_no,
}
static int dw_pcie_ep_inbound_atu(struct dw_pcie_ep *ep, u8 func_no, int type,
- dma_addr_t cpu_addr, enum pci_barno bar)
+ dma_addr_t cpu_addr, enum pci_barno bar,
+ size_t size)
{
int ret;
u32 free_win;
@@ -145,7 +146,7 @@ static int dw_pcie_ep_inbound_atu(struct dw_pcie_ep *ep, u8 func_no, int type,
}
ret = dw_pcie_prog_ep_inbound_atu(pci, func_no, free_win, type,
- cpu_addr, bar);
+ cpu_addr, bar, size);
if (ret < 0) {
dev_err(pci->dev, "Failed to program IB window\n");
return ret;
@@ -265,7 +266,8 @@ static int dw_pcie_ep_set_bar(struct pci_epc *epc, u8 func_no, u8 vfunc_no,
else
type = PCIE_ATU_TYPE_IO;
- ret = dw_pcie_ep_inbound_atu(ep, func_no, type, epf_bar->phys_addr, bar);
+ ret = dw_pcie_ep_inbound_atu(ep, func_no, type, epf_bar->phys_addr, bar,
+ size);
if (ret)
return ret;
diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c
index 6d6cbc8b5b2c..3c683b6119c3 100644
--- a/drivers/pci/controller/dwc/pcie-designware.c
+++ b/drivers/pci/controller/dwc/pcie-designware.c
@@ -597,11 +597,12 @@ int dw_pcie_prog_inbound_atu(struct dw_pcie *pci, int index, int type,
}
int dw_pcie_prog_ep_inbound_atu(struct dw_pcie *pci, u8 func_no, int index,
- int type, u64 cpu_addr, u8 bar)
+ int type, u64 cpu_addr, u8 bar, size_t size)
{
u32 retries, val;
- if (!IS_ALIGNED(cpu_addr, pci->region_align))
+ if (!IS_ALIGNED(cpu_addr, pci->region_align) ||
+ !IS_ALIGNED(cpu_addr, size))
return -EINVAL;
dw_pcie_writel_atu_ib(pci, index, PCIE_ATU_LOWER_TARGET,
diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h
index 347ab74ac35a..fc0872711672 100644
--- a/drivers/pci/controller/dwc/pcie-designware.h
+++ b/drivers/pci/controller/dwc/pcie-designware.h
@@ -491,7 +491,7 @@ int dw_pcie_prog_outbound_atu(struct dw_pcie *pci,
int dw_pcie_prog_inbound_atu(struct dw_pcie *pci, int index, int type,
u64 cpu_addr, u64 pci_addr, u64 size);
int dw_pcie_prog_ep_inbound_atu(struct dw_pcie *pci, u8 func_no, int index,
- int type, u64 cpu_addr, u8 bar);
+ int type, u64 cpu_addr, u8 bar, size_t size);
void dw_pcie_disable_atu(struct dw_pcie *pci, u32 dir, int index);
void dw_pcie_setup(struct dw_pcie *pci);
void dw_pcie_iatu_detect(struct dw_pcie *pci);
--
2.47.1
