diff options
| author | Niklas Cassel <cassel@kernel.org> | 2024-12-13 15:33:04 +0100 |
|---|---|---|
| committer | Krzysztof Wilczyński <kwilczynski@kernel.org> | 2024-12-18 21:51:30 +0000 |
| commit | 129f6af747b2259a4319a0af536fd80ece16e7cb (patch) | |
| tree | 29b43f2c5d8f447e9c58c4d9e33081676c0fbf03 /drivers/pci/controller/dwc/pcie-designware.c | |
| parent | 3708acbd5f169ebafe1faa519cb28adc56295546 (diff) | |
PCI: dwc: ep: Add 'address' alignment to 'size' check in dw_pcie_prog_ep_inbound_atu()
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.
Link: https://lore.kernel.org/r/20241213143301.4158431-11-cassel@kernel.org
Signed-off-by: Niklas Cassel <cassel@kernel.org>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Diffstat (limited to 'drivers/pci/controller/dwc/pcie-designware.c')
| -rw-r--r-- | drivers/pci/controller/dwc/pcie-designware.c | 5 |
1 files changed, 3 insertions, 2 deletions
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, |