On Wed, May 26, 2021 at 7:11 PM Laurentiu Tudor <laurentiu.tudor@xxxxxxx> wrote: > > > > On 5/26/2021 7:36 PM, Shameerali Kolothum Thodi wrote: > > > > > >> -----Original Message----- > >> From: Laurentiu Tudor [mailto:laurentiu.tudor@xxxxxxx] > >> Sent: 26 May 2021 08:53 > >> To: Shameerali Kolothum Thodi <shameerali.kolothum.thodi@xxxxxxxxxx>; > >> linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; linux-acpi@xxxxxxxxxxxxxxx; > >> iommu@xxxxxxxxxxxxxxxxxxxxxxxxxx > >> Cc: jon@xxxxxxxxxxxxx; Linuxarm <linuxarm@xxxxxxxxxx>; > >> steven.price@xxxxxxx; Guohanjun (Hanjun Guo) <guohanjun@xxxxxxxxxx>; > >> yangyicong <yangyicong@xxxxxxxxxx>; Sami.Mujawar@xxxxxxx; > >> robin.murphy@xxxxxxx; wanghuiqiang <wanghuiqiang@xxxxxxxxxx> > >> Subject: Re: [PATCH v5 3/8] ACPI/IORT: Add a helper to retrieve RMR memory > >> regions > >> > >> Hi Shameer, > >> > >> On 5/24/2021 2:02 PM, Shameer Kolothum wrote: > >>> Add a helper function that retrieves RMR memory descriptors > >>> associated with a given IOMMU. This will be used by IOMMU > >>> drivers to setup necessary mappings. > >>> > >>> Now that we have this, invoke it from the generic helper > >>> interface. > >>> > >>> Signed-off-by: Shameer Kolothum > >> <shameerali.kolothum.thodi@xxxxxxxxxx> > >>> --- > >>> drivers/acpi/arm64/iort.c | 50 > >> +++++++++++++++++++++++++++++++++++++++ > >>> drivers/iommu/dma-iommu.c | 4 ++++ > >>> include/linux/acpi_iort.h | 7 ++++++ > >>> 3 files changed, 61 insertions(+) > >>> > >>> diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c > >>> index fea1ffaedf3b..01917caf58de 100644 > >>> --- a/drivers/acpi/arm64/iort.c > >>> +++ b/drivers/acpi/arm64/iort.c > >>> @@ -12,6 +12,7 @@ > >>> > >>> #include <linux/acpi_iort.h> > >>> #include <linux/bitfield.h> > >>> +#include <linux/dma-iommu.h> > >>> #include <linux/iommu.h> > >>> #include <linux/kernel.h> > >>> #include <linux/list.h> > >>> @@ -837,6 +838,53 @@ static inline int iort_add_device_replay(struct > >> device *dev) > >>> return err; > >>> } > >>> > >>> +/** > >>> + * iort_iommu_get_rmrs - Helper to retrieve RMR info associated with > >> IOMMU > >>> + * @iommu: fwnode for the IOMMU > >>> + * @head: RMR list head to be populated > >>> + * > >>> + * Returns: 0 on success, <0 failure > >>> + */ > >>> +int iort_iommu_get_rmrs(struct fwnode_handle *iommu_fwnode, > >>> + struct list_head *head) > >>> +{ > >>> + struct iort_rmr_entry *e; > >>> + struct acpi_iort_node *iommu; > >>> + int rmrs = 0; > >>> + > >>> + iommu = iort_get_iort_node(iommu_fwnode); > >>> + if (!iommu || list_empty(&iort_rmr_list)) > >>> + return -ENODEV; > >>> + > >>> + list_for_each_entry(e, &iort_rmr_list, list) { > >>> + int prot = IOMMU_READ | IOMMU_WRITE | IOMMU_NOEXEC | > >> IOMMU_MMIO; > >> > >> We have a case with an IP block that needs EXEC rights on its reserved > >> memory, so could you please drop the IOMMU_NOEXEC flag? > > > > Ok, I think I can drop that one if there are no other concerns. I was not quite > > sure what to include here in the first place as the IORT spec is not giving any > > further details about the RMR regions(May be the flags field can be extended to > > describe these details). > > > > That would be great, given that some preliminary investigations on my > side revealed that our IP block seems to be quite sensitive to memory > attributes. I need to spend some more time on this but at first sight > looks like it needs cacheable, normal memory (not mmio mapping). > > --- > Thanks & Best Regards, Laurentiu Laurentiu, Is this regarding the mc-bin memory block or another IP? I am currently running this patchset with IOMMU_NOEXEC under ACPI without any problems. If so maybe we can touch base off list and align on the implementation. -Jon
