Re: [PATCH 3/7] iommu/ipmmu-vmsa: Prepare to handle 40-bit error addresses

Laurent Pinchart
2019-02-20T15:31:06Z

Hi Geert,

Thank you for the patch.

On Wed, Feb 20, 2019 at 04:05:27PM +0100, Geert Uytterhoeven wrote:
> On R-Car Gen3, the faulting virtual address is a 40-bit address, and
> comprised of two registers. Read the upper address part, and combine
> both parts, when running on a 64-bit system.
>
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> ---
> Apart from this, the driver doesn't support 40-bit IOVA addresses yet.
> ---
> drivers/iommu/ipmmu-vmsa.c | 16 ++++++++++------
> 1 file changed, 10 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/iommu/ipmmu-vmsa.c b/drivers/iommu/ipmmu-vmsa.c
> index ac70cb967ff821c6..4d07c26c97848b65 100644
> --- a/drivers/iommu/ipmmu-vmsa.c
> +++ b/drivers/iommu/ipmmu-vmsa.c
> @@ -186,7 +186,9 @@ static struct ipmmu_vmsa_device *to_ipmmu(struct device *dev)
> #define IMMAIR_ATTR_IDX_WBRWA 1
> #define IMMAIR_ATTR_IDX_DEV 2
>
> -#define IMEAR 0x0030
> +#define IMEAR 0x0030 /* R-Car Gen2 */
> +#define IMELAR IMEAR /* R-Car Gen3 */

I would have defined that as a single macro.

> +#define IMEUAR 0x0034 /* R-Car Gen3 */
>
> #define IMPCTR 0x0200
> #define IMPSTR 0x0208
> @@ -521,14 +523,16 @@ static irqreturn_t ipmmu_domain_irq(struct ipmmu_vmsa_domain *domain)
> {
> const u32 err_mask = IMSTR_MHIT | IMSTR_ABORT | IMSTR_PF | IMSTR_TF;
> struct ipmmu_vmsa_device *mmu = domain->mmu;
> + unsigned long iova;

Isn't there a more appropriate type, such as dma_addr_t possibly ?

> u32 status;
> - u32 iova;
>
> status = ipmmu_ctx_read_root(domain, IMSTR);
> if (!(status & err_mask))
> return IRQ_NONE;
>
> - iova = ipmmu_ctx_read_root(domain, IMEAR);
> + iova = ipmmu_ctx_read_root(domain, IMELAR);
> + if (IS_ENABLED(CONFIG_64BIT))
> + iova |= (u64)ipmmu_ctx_read_root(domain, IMEUAR) << 32;
>
> /*
> * Clear the error status flags. Unlike traditional interrupt flag
> @@ -540,10 +544,10 @@ static irqreturn_t ipmmu_domain_irq(struct ipmmu_vmsa_domain *domain)
>
> /* Log fatal errors. */
> if (status & IMSTR_MHIT)
> - dev_err_ratelimited(mmu->dev, "Multiple TLB hits @0x%08x\n",
> + dev_err_ratelimited(mmu->dev, "Multiple TLB hits @0x%lx\n",
> iova);
> if (status & IMSTR_ABORT)
> - dev_err_ratelimited(mmu->dev, "Page Table Walk Abort @0x%08x\n",
> + dev_err_ratelimited(mmu->dev, "Page Table Walk Abort @0x%lx\n",
> iova);
>
> if (!(status & (IMSTR_PF | IMSTR_TF)))
> @@ -559,7 +563,7 @@ static irqreturn_t ipmmu_domain_irq(struct ipmmu_vmsa_domain *domain)
> return IRQ_HANDLED;
>
> dev_err_ratelimited(mmu->dev,
> - "Unhandled fault: status 0x%08x iova 0x%08x\n",
> + "Unhandled fault: status 0x%08x iova 0x%lx\n",
> status, iova);
>
> return IRQ_HANDLED;

--
Regards,

Laurent Pinchart