linux-pci.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
* [PATCH] PCI : check if type 0 devices have all BARs of size zero
@ 2021-02-12 10:08 Wasim Khan
  2021-02-15 21:13 ` Bjorn Helgaas
  0 siblings, 1 reply; 4+ messages in thread
From: Wasim Khan @ 2021-02-12 10:08 UTC (permalink / raw)
  To: bhelgaas; +Cc: linux-pci, linux-kernel, Wasim Khan

From: Wasim Khan <wasim.khan@nxp.com>

Log a message if all BARs of type 0 devices are of
size zero. This can help detecting type 0 devices
not reporting BAR size correctly.

Signed-off-by: Wasim Khan <wasim.khan@nxp.com>
---
 drivers/pci/probe.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 953f15abc850..6438d6d56777 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -321,6 +321,7 @@ int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type,
 static void pci_read_bases(struct pci_dev *dev, unsigned int howmany, int rom)
 {
 	unsigned int pos, reg;
+	bool found = false;
 
 	if (dev->non_compliant_bars)
 		return;
@@ -333,8 +334,12 @@ static void pci_read_bases(struct pci_dev *dev, unsigned int howmany, int rom)
 		struct resource *res = &dev->resource[pos];
 		reg = PCI_BASE_ADDRESS_0 + (pos << 2);
 		pos += __pci_read_base(dev, pci_bar_unknown, res, reg);
+		found |= res->flags ? 1 : 0;
 	}
 
+	if (!dev->hdr_type && !found)
+		pci_info(dev, "BAR size is 0 for BAR[0..%d]\n", howmany - 1);
+
 	if (rom) {
 		struct resource *res = &dev->resource[PCI_ROM_RESOURCE];
 		dev->rom_base_reg = rom;
-- 
2.25.1


^ permalink raw reply	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2021-02-16 14:17 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-02-12 10:08 [PATCH] PCI : check if type 0 devices have all BARs of size zero Wasim Khan
2021-02-15 21:13 ` Bjorn Helgaas
2021-02-16  7:52   ` Wasim Khan
2021-02-16 14:16     ` Bjorn Helgaas

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).