* [PATCH v2 1/1] PCI: mediatek: Correct type for virt_to_phys()
@ 2023-09-14 19:23 Andy Shevchenko
2023-09-14 20:31 ` Bjorn Helgaas
0 siblings, 1 reply; 4+ messages in thread
From: Andy Shevchenko @ 2023-09-14 19:23 UTC (permalink / raw)
To: linux-pci, linux-mediatek, linux-kernel, linux-arm-kernel
Cc: Ryder Lee, Jianjun Wang, Lorenzo Pieralisi,
Krzysztof Wilczyński, Rob Herring, Bjorn Helgaas,
Matthias Brugger, AngeloGioacchino Del Regno, Andy Shevchenko,
Huacai Chen, kernel test robot
virt_to_phys() takes a regular pointer, while driver supplies __iomem
annotated one. Force type to void to make sparse happy, otherwise
pcie-mediatek.c:400:40: sparse: expected void volatile *address
pcie-mediatek.c:400:40: sparse: got void [noderef] __iomem *
pcie-mediatek.c:523:44: sparse: expected void volatile *address
pcie-mediatek.c:523:44: sparse: got void [noderef] __iomem *
Reported-by: Huacai Chen <chenhuacai@kernel.org>
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202309072237.9zxMv4MZ-lkp@intel.com/
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
drivers/pci/controller/pcie-mediatek.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/pci/controller/pcie-mediatek.c b/drivers/pci/controller/pcie-mediatek.c
index 66a8f73296fc..5e795afd1cee 100644
--- a/drivers/pci/controller/pcie-mediatek.c
+++ b/drivers/pci/controller/pcie-mediatek.c
@@ -397,7 +397,7 @@ static void mtk_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
phys_addr_t addr;
/* MT2712/MT7622 only support 32-bit MSI addresses */
- addr = virt_to_phys(port->base + PCIE_MSI_VECTOR);
+ addr = virt_to_phys((__force void *)port->base + PCIE_MSI_VECTOR);
msg->address_hi = 0;
msg->address_lo = lower_32_bits(addr);
@@ -520,7 +520,7 @@ static void mtk_pcie_enable_msi(struct mtk_pcie_port *port)
u32 val;
phys_addr_t msg_addr;
- msg_addr = virt_to_phys(port->base + PCIE_MSI_VECTOR);
+ msg_addr = virt_to_phys((__force void *)port->base + PCIE_MSI_VECTOR);
val = lower_32_bits(msg_addr);
writel(val, port->base + PCIE_IMSI_ADDR);
--
2.40.0.1.gaa8946217a0b
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH v2 1/1] PCI: mediatek: Correct type for virt_to_phys()
2023-09-14 19:23 [PATCH v2 1/1] PCI: mediatek: Correct type for virt_to_phys() Andy Shevchenko
@ 2023-09-14 20:31 ` Bjorn Helgaas
2023-09-16 10:41 ` Andy Shevchenko
0 siblings, 1 reply; 4+ messages in thread
From: Bjorn Helgaas @ 2023-09-14 20:31 UTC (permalink / raw)
To: Andy Shevchenko
Cc: linux-pci, linux-mediatek, linux-kernel, linux-arm-kernel,
Ryder Lee, Jianjun Wang, Lorenzo Pieralisi,
Krzysztof Wilczyński, Rob Herring, Bjorn Helgaas,
Matthias Brugger, AngeloGioacchino Del Regno, Huacai Chen,
kernel test robot
On Thu, Sep 14, 2023 at 10:23:24PM +0300, Andy Shevchenko wrote:
> virt_to_phys() takes a regular pointer, while driver supplies __iomem
> annotated one. Force type to void to make sparse happy, otherwise
>
> pcie-mediatek.c:400:40: sparse: expected void volatile *address
> pcie-mediatek.c:400:40: sparse: got void [noderef] __iomem *
>
> pcie-mediatek.c:523:44: sparse: expected void volatile *address
> pcie-mediatek.c:523:44: sparse: got void [noderef] __iomem *
>
> Reported-by: Huacai Chen <chenhuacai@kernel.org>
> Reported-by: kernel test robot <lkp@intel.com>
> Closes: https://lore.kernel.org/oe-kbuild-all/202309072237.9zxMv4MZ-lkp@intel.com/
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> ---
> drivers/pci/controller/pcie-mediatek.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/pci/controller/pcie-mediatek.c b/drivers/pci/controller/pcie-mediatek.c
> index 66a8f73296fc..5e795afd1cee 100644
> --- a/drivers/pci/controller/pcie-mediatek.c
> +++ b/drivers/pci/controller/pcie-mediatek.c
> @@ -397,7 +397,7 @@ static void mtk_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
> phys_addr_t addr;
>
> /* MT2712/MT7622 only support 32-bit MSI addresses */
> - addr = virt_to_phys(port->base + PCIE_MSI_VECTOR);
> + addr = virt_to_phys((__force void *)port->base + PCIE_MSI_VECTOR);
Lots of these drivers use either virt_to_phys() or
platform_get_resource_byname() to get a physical address that they
then use as the MSI target.
But I don't think that's quite right -- the MSI is a DMA transaction
on PCI, and in general there's no guarantee that bus addresses are
identical to CPU physical addresses, so shouldn't we use a dma_addr_t
obtained from the DMA API?
dw_pcie_msi_host_init() has a complicated version of this that uses
dmam_alloc_coherent().
> msg->address_hi = 0;
> msg->address_lo = lower_32_bits(addr);
>
> @@ -520,7 +520,7 @@ static void mtk_pcie_enable_msi(struct mtk_pcie_port *port)
> u32 val;
> phys_addr_t msg_addr;
>
> - msg_addr = virt_to_phys(port->base + PCIE_MSI_VECTOR);
> + msg_addr = virt_to_phys((__force void *)port->base + PCIE_MSI_VECTOR);
> val = lower_32_bits(msg_addr);
> writel(val, port->base + PCIE_IMSI_ADDR);
>
> --
> 2.40.0.1.gaa8946217a0b
>
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH v2 1/1] PCI: mediatek: Correct type for virt_to_phys()
2023-09-14 20:31 ` Bjorn Helgaas
@ 2023-09-16 10:41 ` Andy Shevchenko
2023-09-18 21:14 ` Bjorn Helgaas
0 siblings, 1 reply; 4+ messages in thread
From: Andy Shevchenko @ 2023-09-16 10:41 UTC (permalink / raw)
To: Bjorn Helgaas
Cc: linux-pci, linux-mediatek, linux-kernel, linux-arm-kernel,
Ryder Lee, Jianjun Wang, Lorenzo Pieralisi,
Krzysztof Wilczyński, Rob Herring, Bjorn Helgaas,
Matthias Brugger, AngeloGioacchino Del Regno, Huacai Chen,
kernel test robot
On Thu, Sep 14, 2023 at 03:31:46PM -0500, Bjorn Helgaas wrote:
> On Thu, Sep 14, 2023 at 10:23:24PM +0300, Andy Shevchenko wrote:
...
> > - addr = virt_to_phys(port->base + PCIE_MSI_VECTOR);
> > + addr = virt_to_phys((__force void *)port->base + PCIE_MSI_VECTOR);
>
> Lots of these drivers use either virt_to_phys() or
> platform_get_resource_byname() to get a physical address that they
> then use as the MSI target.
>
> But I don't think that's quite right -- the MSI is a DMA transaction
> on PCI, and in general there's no guarantee that bus addresses are
> identical to CPU physical addresses, so shouldn't we use a dma_addr_t
> obtained from the DMA API?
>
> dw_pcie_msi_host_init() has a complicated version of this that uses
> dmam_alloc_coherent().
Fair enough. I leave it to you then to get it fixed properly.
Consider this as just a heads up for the old report.
--
With Best Regards,
Andy Shevchenko
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH v2 1/1] PCI: mediatek: Correct type for virt_to_phys()
2023-09-16 10:41 ` Andy Shevchenko
@ 2023-09-18 21:14 ` Bjorn Helgaas
0 siblings, 0 replies; 4+ messages in thread
From: Bjorn Helgaas @ 2023-09-18 21:14 UTC (permalink / raw)
To: Andy Shevchenko
Cc: linux-pci, linux-mediatek, linux-kernel, linux-arm-kernel,
Ryder Lee, Jianjun Wang, Lorenzo Pieralisi,
Krzysztof Wilczyński, Rob Herring, Bjorn Helgaas,
Matthias Brugger, AngeloGioacchino Del Regno, Huacai Chen,
kernel test robot
On Sat, Sep 16, 2023 at 01:41:59PM +0300, Andy Shevchenko wrote:
> On Thu, Sep 14, 2023 at 03:31:46PM -0500, Bjorn Helgaas wrote:
> > On Thu, Sep 14, 2023 at 10:23:24PM +0300, Andy Shevchenko wrote:
>
> ...
>
> > > - addr = virt_to_phys(port->base + PCIE_MSI_VECTOR);
> > > + addr = virt_to_phys((__force void *)port->base + PCIE_MSI_VECTOR);
> >
> > Lots of these drivers use either virt_to_phys() or
> > platform_get_resource_byname() to get a physical address that they
> > then use as the MSI target.
> >
> > But I don't think that's quite right -- the MSI is a DMA transaction
> > on PCI, and in general there's no guarantee that bus addresses are
> > identical to CPU physical addresses, so shouldn't we use a dma_addr_t
> > obtained from the DMA API?
> >
> > dw_pcie_msi_host_init() has a complicated version of this that uses
> > dmam_alloc_coherent().
>
> Fair enough. I leave it to you then to get it fixed properly.
> Consider this as just a heads up for the old report.
Sounds good, thanks!
Bjorn
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2023-09-18 21:14 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2023-09-14 19:23 [PATCH v2 1/1] PCI: mediatek: Correct type for virt_to_phys() Andy Shevchenko
2023-09-14 20:31 ` Bjorn Helgaas
2023-09-16 10:41 ` Andy Shevchenko
2023-09-18 21:14 ` 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).