Re: [PATCH kernel v2] powerpc/pci: Fix broken INTx configuration via OF
From: Michael Ellerman <mpe@ellerman.id.au>
Date: 2018-02-09 05:54:12
Also in:
linux-pci
Alexey Kardashevskiy [off-list ref] writes:
Commit 59f47eff03a0 ("powerpc/pci: Use of_irq_parse_and_map_pci() helper")
replaced of_irq_parse_pci() + irq_create_of_mapping() with
of_irq_parse_and_map_pci() but this change lost virq returned by
irq_create_of_mapping() so virq remained zero causing INTx
misconfiguration.
This fixes pci_read_irq_line() not to loose a virq returned by
of_irq_parse_and_map_pci().
Fixes: 59f47eff03a0 "powerpc/pci: Use of_irq_parse_and_map_pci() helper"
Signed-off-by: Alexey Kardashevskiy <redacted>
---
Changes:
v2:
* changed the condition from <=0 to !=0 as by design
of_irq_parse_and_map_pci() can only return 0 for an error and virq>0.It returns int, so you should store the result in an int, and check the result for <= 0. Otherwise if it starts returning a negative error value this code will break. If it's a problem that of_irq_parse_and_map_pci() might internally convert an unsigned virq to int then we need to fix that there, or make of_irq_parse_and_map_pci() return unsigned also. cheers
quoted hunk ↗ jump to hunk
diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c index ae2ede4..33580a9 100644 --- a/arch/powerpc/kernel/pci-common.c +++ b/arch/powerpc/kernel/pci-common.c@@ -362,7 +362,7 @@ struct pci_controller* pci_find_hose_for_OF_device(struct device_node* node) */ static int pci_read_irq_line(struct pci_dev *pci_dev) { - unsigned int virq = 0; + unsigned int virq; pr_debug("PCI: Try to map irq for %s...\n", pci_name(pci_dev));@@ -370,7 +370,8 @@ static int pci_read_irq_line(struct pci_dev *pci_dev) memset(&oirq, 0xff, sizeof(oirq)); #endif /* Try to get a mapping from the device-tree */ - if (!of_irq_parse_and_map_pci(pci_dev, 0, 0)) { + virq = of_irq_parse_and_map_pci(pci_dev, 0, 0); + if (!virq) { u8 line, pin; /* If that fails, lets fallback to what is in the config-- 2.11.0