From patchwork Wed Apr 8 22:57:29 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Simon Glass X-Patchwork-Id: 237467 List-Id: U-Boot discussion From: sjg at chromium.org (Simon Glass) Date: Wed, 8 Apr 2020 16:57:29 -0600 Subject: [PATCH v5 10/29] pci: Adjust dm_pci_read_bar32() to return errors correctly In-Reply-To: <20200408225749.171380-1-sjg@chromium.org> References: <20200408225749.171380-1-sjg@chromium.org> Message-ID: <20200408165737.v5.10.I36321d5e30daf051900f01f6289dfc58439871ea@changeid> At present if reading a BAR returns 0xffffffff (e.g. the device is not present) then the value is masked and a different value is returned. This makes it harder to detect the problem when debugging. Update the function to avoid masking in this case. Signed-off-by: Simon Glass Reviewed-by: Bin Meng Reviewed-by: Wolfgang Wallner --- Changes in v5: None Changes in v4: None Changes in v3: None Changes in v2: None drivers/pci/pci-uclass.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/drivers/pci/pci-uclass.c b/drivers/pci/pci-uclass.c index 213381da6bd..7f46e901fb2 100644 --- a/drivers/pci/pci-uclass.c +++ b/drivers/pci/pci-uclass.c @@ -1213,7 +1213,14 @@ u32 dm_pci_read_bar32(const struct udevice *dev, int barnum) bar = PCI_BASE_ADDRESS_0 + barnum * 4; dm_pci_read_config32(dev, bar, &addr); - if (addr & PCI_BASE_ADDRESS_SPACE_IO) + + /* + * If we get an invalid address, return this so that comparisons with + * FDT_ADDR_T_NONE work correctly + */ + if (addr == 0xffffffff) + return addr; + else if (addr & PCI_BASE_ADDRESS_SPACE_IO) return addr & PCI_BASE_ADDRESS_IO_MASK; else return addr & PCI_BASE_ADDRESS_MEM_MASK;