lkml.org 
[lkml]   [2020]   [Feb]   [3]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    Date
    From
    SubjectRe: [PATCH v2 07/27] ocxl: Add functions to map/unmap LPC memory
    On Tue, 3 Dec 2019 14:46:35 +1100
    Alastair D'Silva <alastair@au1.ibm.com> wrote:

    > From: Alastair D'Silva <alastair@d-silva.org>
    >
    > Add functions to map/unmap LPC memory
    >
    > Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
    > ---
    > drivers/misc/ocxl/config.c | 4 +++
    > drivers/misc/ocxl/core.c | 50 +++++++++++++++++++++++++++++++
    > drivers/misc/ocxl/ocxl_internal.h | 3 ++
    > include/misc/ocxl.h | 18 +++++++++++
    > 4 files changed, 75 insertions(+)
    >
    > diff --git a/drivers/misc/ocxl/config.c b/drivers/misc/ocxl/config.c
    > index c8e19bfb5ef9..fb0c3b6f8312 100644
    > --- a/drivers/misc/ocxl/config.c
    > +++ b/drivers/misc/ocxl/config.c
    > @@ -568,6 +568,10 @@ static int read_afu_lpc_memory_info(struct pci_dev *dev,
    > afu->special_purpose_mem_size =
    > total_mem_size - lpc_mem_size;
    > }
    > +
    > + dev_info(&dev->dev, "Probed LPC memory of %#llx bytes and special purpose memory of %#llx bytes\n",
    > + afu->lpc_mem_size, afu->special_purpose_mem_size);
    > +

    If we are being fussy, this block has nothing todo with the rest of the patch
    so we should be seeing it here.

    > return 0;
    > }
    >
    > diff --git a/drivers/misc/ocxl/core.c b/drivers/misc/ocxl/core.c
    > index 2531c6cf19a0..98611faea219 100644
    > --- a/drivers/misc/ocxl/core.c
    > +++ b/drivers/misc/ocxl/core.c
    > @@ -210,6 +210,55 @@ static void unmap_mmio_areas(struct ocxl_afu *afu)
    > release_fn_bar(afu->fn, afu->config.global_mmio_bar);
    > }
    >
    > +int ocxl_afu_map_lpc_mem(struct ocxl_afu *afu)
    > +{
    > + struct pci_dev *dev = to_pci_dev(afu->fn->dev.parent);
    > +
    > + if ((afu->config.lpc_mem_size + afu->config.special_purpose_mem_size) == 0)
    > + return 0;
    > +
    > + afu->lpc_base_addr = ocxl_link_lpc_map(afu->fn->link, dev);
    > + if (afu->lpc_base_addr == 0)
    > + return -EINVAL;
    > +
    > + if (afu->config.lpc_mem_size) {

    I was happy with the explicit check on 0 above, but we should be consistent. Either
    we make use of 0 == false, or we don't and explicitly check vs 0.

    Hence

    if (afu->config.pc_mem_size != 0) {

    here or

    if (!(afu->config.pc_mem_size + afu->config.special_purpose_mem_size))
    return 0;

    above.

    > + afu->lpc_res.start = afu->lpc_base_addr + afu->config.lpc_mem_offset;
    > + afu->lpc_res.end = afu->lpc_res.start + afu->config.lpc_mem_size - 1;
    > + }
    > +
    > + if (afu->config.special_purpose_mem_size) {
    > + afu->special_purpose_res.start = afu->lpc_base_addr +
    > + afu->config.special_purpose_mem_offset;
    > + afu->special_purpose_res.end = afu->special_purpose_res.start +
    > + afu->config.special_purpose_mem_size - 1;
    > + }
    > +
    > + return 0;
    > +}
    > +EXPORT_SYMBOL_GPL(ocxl_afu_map_lpc_mem);
    > +
    > +struct resource *ocxl_afu_lpc_mem(struct ocxl_afu *afu)
    > +{
    > + return &afu->lpc_res;
    > +}
    > +EXPORT_SYMBOL_GPL(ocxl_afu_lpc_mem);
    > +
    > +static void unmap_lpc_mem(struct ocxl_afu *afu)
    > +{
    > + struct pci_dev *dev = to_pci_dev(afu->fn->dev.parent);
    > +
    > + if (afu->lpc_res.start || afu->special_purpose_res.start) {
    > + void *link = afu->fn->link;
    > +
    > + ocxl_link_lpc_release(link, dev);
    > +
    > + afu->lpc_res.start = 0;
    > + afu->lpc_res.end = 0;
    > + afu->special_purpose_res.start = 0;
    > + afu->special_purpose_res.end = 0;
    > + }
    > +}
    > +
    > static int configure_afu(struct ocxl_afu *afu, u8 afu_idx, struct pci_dev *dev)
    > {
    > int rc;
    > @@ -251,6 +300,7 @@ static int configure_afu(struct ocxl_afu *afu, u8 afu_idx, struct pci_dev *dev)
    >
    > static void deconfigure_afu(struct ocxl_afu *afu)
    > {
    > + unmap_lpc_mem(afu);

    Hmm. This breaks the existing balance between configure_afu and deconfigure_afu.

    Given comments below on why we don't do map_lpc_mem in the afu bring up
    (as it's a shared operation) it seems to me that we should be doing this
    outside of the afu deconfigure. Perhaps ocxl_function_close is appropriate?
    I don't know this infrastructure well enough to be sure.

    If it does need to be here, then a comment to give more info on
    why would be great!

    > unmap_mmio_areas(afu);
    > reclaim_afu_pasid(afu);
    > reclaim_afu_actag(afu);
    > diff --git a/drivers/misc/ocxl/ocxl_internal.h b/drivers/misc/ocxl/ocxl_internal.h
    > index 20b417e00949..9f4b47900e62 100644
    > --- a/drivers/misc/ocxl/ocxl_internal.h
    > +++ b/drivers/misc/ocxl/ocxl_internal.h
    > @@ -52,6 +52,9 @@ struct ocxl_afu {
    > void __iomem *global_mmio_ptr;
    > u64 pp_mmio_start;
    > void *private;
    > + u64 lpc_base_addr; /* Covers both LPC & special purpose memory */
    > + struct resource lpc_res;
    > + struct resource special_purpose_res;
    > };
    >
    > enum ocxl_context_status {
    > diff --git a/include/misc/ocxl.h b/include/misc/ocxl.h
    > index 06dd5839e438..6f7c02f0d5e3 100644
    > --- a/include/misc/ocxl.h
    > +++ b/include/misc/ocxl.h
    > @@ -212,6 +212,24 @@ int ocxl_irq_set_handler(struct ocxl_context *ctx, int irq_id,
    >
    > // AFU Metadata
    >
    > +/**
    > + * Map the LPC system & special purpose memory for an AFU
    > + *
    > + * Do not call this during device discovery, as there may me multiple
    > + * devices on a link, and the memory is mapped for the whole link, not
    > + * just one device. It should only be called after all devices have
    > + * registered their memory on the link.
    > + *
    > + * afu: The AFU that has the LPC memory to map
    Run kernel-doc over these files and fix all the errors + warnings.

    @afu: ..

    and missing function name etc.


    > + */
    > +extern int ocxl_afu_map_lpc_mem(struct ocxl_afu *afu);
    > +
    > +/**
    > + * Get the physical address range of LPC memory for an AFU
    > + * afu: The AFU associated with the LPC memory
    > + */
    > +extern struct resource *ocxl_afu_lpc_mem(struct ocxl_afu *afu);
    > +
    > /**
    > * Get a pointer to the config for an AFU
    > *

    \
     
     \ /
      Last update: 2020-02-03 13:50    [W:2.694 / U:0.008 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site