From: Huacai Chen <chenhuacai@loongson.cn>
To: "Bjorn Helgaas" <bhelgaas@google.com>,
"Lorenzo Pieralisi" <lorenzo.pieralisi@arm.com>,
"Rob Herring" <robh@kernel.org>,
"Krzysztof Wilczyński" <kw@linux.com>
Cc: linux-pci@vger.kernel.org, Xuefeng Li <lixuefeng@loongson.cn>,
Huacai Chen <chenhuacai@gmail.com>,
Jiaxun Yang <jiaxun.yang@flygoat.com>,
Huacai Chen <chenhuacai@loongson.cn>
Subject: [PATCH V13 3/6] PCI: loongson: Don't access unexisting devices
Date: Sat, 30 Apr 2022 16:48:43 +0800 [thread overview]
Message-ID: <20220430084846.3127041-4-chenhuacai@loongson.cn> (raw)
In-Reply-To: <20220430084846.3127041-1-chenhuacai@loongson.cn>
On LS2K/LS7A, some unexisting devices don't return 0xffffffff when
scanning. This is a hardware flaw but we can only avoid it by software
now.
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
---
drivers/pci/controller/pci-loongson.c | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)
diff --git a/drivers/pci/controller/pci-loongson.c b/drivers/pci/controller/pci-loongson.c
index adbfa4a2330f..48316daa1f23 100644
--- a/drivers/pci/controller/pci-loongson.c
+++ b/drivers/pci/controller/pci-loongson.c
@@ -138,6 +138,8 @@ static void __iomem *pci_loongson_map_bus(struct pci_bus *bus, unsigned int devf
int where)
{
unsigned char busnum = bus->number;
+ unsigned int device = PCI_SLOT(devfn);
+ unsigned int function = PCI_FUNC(devfn);
struct loongson_pci *priv = pci_bus_to_loongson_pci(bus);
if (pci_is_root_bus(bus))
@@ -147,8 +149,13 @@ static void __iomem *pci_loongson_map_bus(struct pci_bus *bus, unsigned int devf
* Do not read more than one device on the bus other than
* the host bus. For our hardware the root bus is always bus 0.
*/
- if (priv->data->flags & FLAG_DEV_FIX &&
- !pci_is_root_bus(bus) && PCI_SLOT(devfn) > 0)
+ if ((priv->data->flags & FLAG_DEV_FIX) && bus->self) {
+ if (!pci_is_root_bus(bus) && (device > 0))
+ return NULL;
+ }
+
+ /* Don't access unexisting devices */
+ if (pci_is_root_bus(bus) && (device >= 9 && device <= 20 && function > 0))
return NULL;
/* CFG0 can only access standard space */
--
2.27.0
next prev parent reply other threads:[~2022-04-30 8:49 UTC|newest]
Thread overview: 35+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-04-30 8:48 [PATCH V13 0/6] PCI: Loongson pci improvements and quirks Huacai Chen
2022-04-30 8:48 ` [PATCH V13 1/6] PCI: loongson: Use generic 8/16/32-bit config ops on LS2K/LS7A Huacai Chen
2022-06-01 2:08 ` Bjorn Helgaas
2022-06-02 4:18 ` Huacai Chen
2022-04-30 8:48 ` [PATCH V13 2/6] PCI: loongson: Add ACPI init support Huacai Chen
2022-05-31 23:04 ` Bjorn Helgaas
2022-06-02 7:09 ` Huacai Chen
2022-04-30 8:48 ` Huacai Chen [this message]
2022-05-31 23:14 ` [PATCH V13 3/6] PCI: loongson: Don't access unexisting devices Bjorn Helgaas
2022-06-02 4:28 ` Huacai Chen
2022-06-02 16:23 ` Bjorn Helgaas
2022-06-02 20:00 ` Jiaxun Yang
2022-04-30 8:48 ` [PATCH V13 4/6] PCI: loongson: Improve the MRRS quirk for LS7A Huacai Chen
2022-06-01 2:22 ` Bjorn Helgaas
2022-06-01 11:59 ` Jiaxun Yang
2022-06-02 4:17 ` Huacai Chen
2022-06-02 16:20 ` Bjorn Helgaas
2022-06-03 12:13 ` Krzysztof Hałasa
2022-06-03 22:57 ` Jiaxun Yang
2022-06-04 0:07 ` Bjorn Helgaas
2022-06-08 8:29 ` Huacai Chen
2022-04-30 8:48 ` [PATCH V13 5/6] PCI: Add quirk for LS7A to avoid reboot failure Huacai Chen
2022-05-31 23:35 ` Bjorn Helgaas
2022-06-02 12:48 ` Huacai Chen
2022-06-02 16:29 ` Bjorn Helgaas
2022-06-08 9:34 ` Huacai Chen
2022-06-08 19:31 ` Bjorn Helgaas
2022-06-16 8:39 ` Huacai Chen
2022-06-16 22:57 ` Bjorn Helgaas
2022-06-17 2:21 ` Huacai Chen
2022-06-17 11:37 ` Bjorn Helgaas
2022-06-17 12:14 ` Huacai Chen
2022-04-30 8:48 ` [PATCH V13 6/6] PCI: Add quirk for multifunction devices of LS7A Huacai Chen
2022-06-01 2:07 ` Bjorn Helgaas
2022-06-01 7:36 ` Jianmin Lv
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