RE: [PATCH v2 14/27] nvdimm/ocxl: Add support for near storage commands

Alastair D'Silva
2020-02-19T04:54:56Z

On Mon, 2020-02-03 at 14:22 +0000, Jonathan Cameron wrote:
> On Tue, 3 Dec 2019 14:46:42 +1100
> Alastair D'Silva <alastair@au1.ibm.com> wrote:
>
> > From: Alastair D'Silva <alastair@d-silva.org>
> >
> > Similar to the previous patch, this adds support for near storage
> > commands.
> >
> > Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
> > ---
> > drivers/nvdimm/ocxl/scm.c | 6 +++++
> > drivers/nvdimm/ocxl/scm_internal.c | 41
> > ++++++++++++++++++++++++++++++
> > drivers/nvdimm/ocxl/scm_internal.h | 38
> > +++++++++++++++++++++++++++
> > 3 files changed, 85 insertions(+)
> >
> > diff --git a/drivers/nvdimm/ocxl/scm.c b/drivers/nvdimm/ocxl/scm.c
> > index 1e175f3c3cf2..6c16ca7fabfa 100644
> > --- a/drivers/nvdimm/ocxl/scm.c
> > +++ b/drivers/nvdimm/ocxl/scm.c
> > @@ -310,12 +310,18 @@ static int scm_setup_command_metadata(struct
> > scm_data *scm_data)
> > int rc;
> >
> > mutex_init(&scm_data->admin_command.lock);
> > + mutex_init(&scm_data->ns_command.lock);
> >
> > rc = scm_extract_command_metadata(scm_data,
> > GLOBAL_MMIO_ACMA_CREQO,
> > &scm_data->admin_command);
> > if (rc)
> > return rc;
> >
> > + rc = scm_extract_command_metadata(scm_data,
> > GLOBAL_MMIO_NSCMA_CREQO,
> > + &scm_data->ns_command);
> > + if (rc)
> > + return rc;
> > +
>
> Ah. So much for my comment in previous patch. Ignore that...
>
> > return 0;
> > }
> >
> > diff --git a/drivers/nvdimm/ocxl/scm_internal.c
> > b/drivers/nvdimm/ocxl/scm_internal.c
> > index 7b11b56863fb..c405f1d8afb8 100644
> > --- a/drivers/nvdimm/ocxl/scm_internal.c
> > +++ b/drivers/nvdimm/ocxl/scm_internal.c
> > @@ -132,6 +132,47 @@ int scm_admin_response_handled(const struct
> > scm_data *scm_data)
> > OCXL_LITTLE_ENDIAN,
> > GLOBAL_MMIO_CHI_ACRA);
> > }
> >
> > +int scm_ns_command_request(struct scm_data *scm_data, u8 op_code)
> > +{
> > + u64 val;
> > + int rc = ocxl_global_mmio_read64(scm_data->ocxl_afu,
> > GLOBAL_MMIO_CHI,
> > + OCXL_LITTLE_ENDIAN, &val);
> > + if (rc)
> > + return rc;
> > +
> > + if (!(val & GLOBAL_MMIO_CHI_NSCRA))
> > + return -EBUSY;
> > +
> > + return scm_command_request(scm_data, &scm_data->ns_command,
> > op_code);
> > +}
> > +
> > +int scm_ns_response(const struct scm_data *scm_data)
> > +{
> > + return scm_command_response(scm_data, &scm_data->ns_command);
> > +}
> > +
> > +int scm_ns_command_execute(const struct scm_data *scm_data)
> > +{
> > + return ocxl_global_mmio_set64(scm_data->ocxl_afu,
> > GLOBAL_MMIO_HCI,
> > + OCXL_LITTLE_ENDIAN,
> > GLOBAL_MMIO_HCI_NSCRW);
> > +}
> > +
> > +bool scm_ns_command_complete(const struct scm_data *scm_data)
> > +{
> > + u64 val = 0;
> > + int rc = scm_chi(scm_data, &val);
> > +
> > + WARN_ON(rc);
> > +
> > + return (val & GLOBAL_MMIO_CHI_NSCRA) != 0;
> > +}
> > +
> > +int scm_ns_response_handled(const struct scm_data *scm_data)
> > +{
> > + return ocxl_global_mmio_set64(scm_data->ocxl_afu,
> > GLOBAL_MMIO_CHIC,
> > + OCXL_LITTLE_ENDIAN,
> > GLOBAL_MMIO_CHI_NSCRA);
> > +}
> > +
> > void scm_warn_status(const struct scm_data *scm_data, const char
> > *message,
> > u8 status)
> > {
> > diff --git a/drivers/nvdimm/ocxl/scm_internal.h
> > b/drivers/nvdimm/ocxl/scm_internal.h
> > index 9bff684cd069..9575996a89e7 100644
> > --- a/drivers/nvdimm/ocxl/scm_internal.h
> > +++ b/drivers/nvdimm/ocxl/scm_internal.h
> > @@ -108,6 +108,7 @@ struct scm_data {
> > struct ocxl_context *ocxl_context;
> > void *metadata_addr;
> > struct command_metadata admin_command;
> > + struct command_metadata ns_command;
> > struct resource scm_res;
> > struct nd_region *nd_region;
> > char fw_version[8+1];
> > @@ -176,6 +177,42 @@ int scm_admin_command_complete_timeout(const
> > struct scm_data *scm_data,
> > */
> > int scm_admin_response_handled(const struct scm_data *scm_data);
> >
> > +/**
> > + * scm_ns_command_request() - Issue a near storage command request
> > + * @scm_data: a pointer to the SCM device data
> > + * @op_code: The op-code for the command
> > + * Returns an identifier for the command, or negative on error
> > + */
> > +int scm_ns_command_request(struct scm_data *scm_data, u8 op_code);
> > +
> > +/**
> > + * scm_ns_response() - Validate a near storage response
> > + * @scm_data: a pointer to the SCM device data
> > + * Returns the status code of the command, or negative on error
> > + */
> > +int scm_ns_response(const struct scm_data *scm_data);
> > +
> > +/**
> > + * scm_ns_command_execute() - Notify the controller to start
> > processing a pending near storage command
> > + * @scm_data: a pointer to the SCM device data
> > + * Returns 0 on success, negative on error
> > + */
> > +int scm_ns_command_execute(const struct scm_data *scm_data);
> > +
> > +/**
> > + * scm_ns_command_complete() - Is a near storage command executing
> > + * scm_data: a pointer to the SCM device data
> > + * Returns true if the previous admin command has completed
> > + */
> > +bool scm_ns_command_complete(const struct scm_data *scm_data);
> > +
> > +/**
> > + * scm_ns_response_handled() - Notify the controller that the near
> > storage response has been handled
> > + * scm_data: a pointer to the SCM device data
> > + * Returns 0 on success, negative on failure
> > + */
> > +int scm_ns_response_handled(const struct scm_data *scm_data);
> > +
> > /**
> > * scm_warn_status() - Emit a kernel warning showing a command
> > status.
> > * @scm_data: a pointer to the SCM device data
> > @@ -184,3 +221,4 @@ int scm_admin_response_handled(const struct
> > scm_data *scm_data);
> > */
> > void scm_warn_status(const struct scm_data *scm_data, const char
> > *message,
> > u8 status);
> > +
> Stray blank line!
Ok

>
> Now we are into the real nitpicks. Not enough coffee.
>
> Jonathan
>
--
Alastair D'Silva
Open Source Developer
Linux Technology Centre, IBM Australia
mob: 0423 762 819