The patch-set adds necessary scaffolding in libndctl for dimms that support papr_scm specification[1]. Since there can be platforms that support Open-Firmware[2] but not the papr_scm specification, hence the changes proposed first add support for probing if the dimm bus supports Open-Firmware. This is done via querying for sysfs attribute 'of_node' in dimm device sysfs directory. If available newly introduced member 'struct ndctl_bus.has_of_node' is set.
During the probe of the dimm and execution of add_dimm(), the newly introduced add_of_pmem_dimm() is called if dimm bus reports supports Open-Firmware. Function add_of_pmem_dimm() queries the 'compatible' device tree attribute and based on its value assign NVDIMM_FAMILY_PAPR_SCM to the dimm command family. In future based on the contents of 'compatible' attribute more of_pmem dimm families can be queried. Presently the dimm-ops implementation for NVDIMM_FAMILY_PAPR_SCM is available in global variable 'papr_scm_dimm_ops' which is a NULL pointer. Subsequent patches will provide a working dimm-ops implementation pointed to by 'papr_scm_dimm_ops'. References: [1] : https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git/commit/?id=58b278f568f0509497e2df7310bfd719156a60d1 [2] : https://en.wikipedia.org/wiki/Open_Firmware Signed-off-by: Vaibhav Jain <[email protected]> --- ndctl/lib/libndctl.c | 42 ++++++++++++++++++++++++++++++++++++++++++ ndctl/lib/private.h | 2 ++ ndctl/libndctl.h | 1 + ndctl/ndctl.h | 1 + 4 files changed, 46 insertions(+) diff --git a/ndctl/lib/libndctl.c b/ndctl/lib/libndctl.c index a5f5fdac9f48..650406d27512 100644 --- a/ndctl/lib/libndctl.c +++ b/ndctl/lib/libndctl.c @@ -858,6 +858,12 @@ static void *add_bus(void *parent, int id, const char *ctl_base) bus->revision = strtoul(buf, NULL, 0); } + sprintf(path, "%s/device/of_node/compatible", ctl_base); + if (sysfs_read_attr(ctx, path, buf) < 0) + bus->has_of_node = 0; + else + bus->has_of_node = 1; + sprintf(path, "%s/device/nfit/dsm_mask", ctl_base); if (sysfs_read_attr(ctx, path, buf) < 0) bus->nfit_dsm_mask = 0; @@ -966,6 +972,10 @@ NDCTL_EXPORT int ndctl_bus_has_nfit(struct ndctl_bus *bus) return bus->has_nfit; } +NDCTL_EXPORT int ndctl_bus_has_of_node(struct ndctl_bus *bus) +{ + return bus->has_of_node; +} /** * ndctl_bus_get_major - nd bus character device major number * @bus: ndctl_bus instance returned from ndctl_bus_get_{first|next} @@ -1405,6 +1415,34 @@ static int ndctl_bind(struct ndctl_ctx *ctx, struct kmod_module *module, static int ndctl_unbind(struct ndctl_ctx *ctx, const char *devpath); static struct kmod_module *to_module(struct ndctl_ctx *ctx, const char *alias); +static int add_of_pmem_dimm(struct ndctl_dimm *dimm, const char *dimm_base) +{ + int rc = -ENODEV; + char buf[SYSFS_ATTR_SIZE]; + struct ndctl_ctx *ctx = dimm->bus->ctx; + char *path = calloc(1, strlen(dimm_base) + 100); + + dbg(ctx, "Probing of_pmem dimm %d at %s\n", dimm->id, dimm_base); + + if (!path) + return -ENOMEM; + + sprintf(path, "%s/../of_node/compatible", dimm_base); + if (sysfs_read_attr(ctx, path, buf) < 0) + goto out; + + + dbg(ctx, "Compatible of_pmem dimm %d at %s\n", dimm->id, buf); + if (strcmp(buf, "ibm,pmemory") == 0) { + dimm->cmd_family = NVDIMM_FAMILY_PAPR_SCM; + rc = 0; + goto out; + } +out: + free(path); + return rc; +} + static int add_nfit_dimm(struct ndctl_dimm *dimm, const char *dimm_base) { int i, rc = -1; @@ -1583,6 +1621,8 @@ static void *add_dimm(void *parent, int id, const char *dimm_base) if (ndctl_bus_has_nfit(bus)) { dimm->formats = formats; rc = add_nfit_dimm(dimm, dimm_base); + } else if (ndctl_bus_has_of_node(bus)) { + rc = add_of_pmem_dimm(dimm, dimm_base); } if (rc == -ENODEV) { @@ -1600,6 +1640,8 @@ static void *add_dimm(void *parent, int id, const char *dimm_base) dimm->ops = msft_dimm_ops; if (dimm->cmd_family == NVDIMM_FAMILY_HYPERV) dimm->ops = hyperv_dimm_ops; + if (dimm->cmd_family == NVDIMM_FAMILY_PAPR_SCM) + dimm->ops = papr_scm_dimm_ops; /* Call the dimm initialization function if needed */ if (!rc && dimm->ops && dimm->ops->dimm_init) diff --git a/ndctl/lib/private.h b/ndctl/lib/private.h index fb7fa47f1f37..16754eda7634 100644 --- a/ndctl/lib/private.h +++ b/ndctl/lib/private.h @@ -167,6 +167,7 @@ struct ndctl_bus { int dimms_init; int regions_init; int has_nfit; + int has_of_node; char *bus_path; char *bus_buf; size_t buf_len; @@ -351,6 +352,7 @@ struct ndctl_dimm_ops * const intel_dimm_ops; struct ndctl_dimm_ops * const hpe1_dimm_ops; struct ndctl_dimm_ops * const msft_dimm_ops; struct ndctl_dimm_ops * const hyperv_dimm_ops; +struct ndctl_dimm_ops * const papr_scm_dimm_ops; static inline struct ndctl_bus *cmd_to_bus(struct ndctl_cmd *cmd) { diff --git a/ndctl/libndctl.h b/ndctl/libndctl.h index 9a53049e7f61..32202654885a 100644 --- a/ndctl/libndctl.h +++ b/ndctl/libndctl.h @@ -119,6 +119,7 @@ struct ndctl_bus *ndctl_bus_get_next(struct ndctl_bus *bus); bus = ndctl_bus_get_next(bus)) struct ndctl_ctx *ndctl_bus_get_ctx(struct ndctl_bus *bus); int ndctl_bus_has_nfit(struct ndctl_bus *bus); +int ndctl_bus_has_of_node(struct ndctl_bus *bus); unsigned int ndctl_bus_get_major(struct ndctl_bus *bus); unsigned int ndctl_bus_get_minor(struct ndctl_bus *bus); const char *ndctl_bus_get_devname(struct ndctl_bus *bus); diff --git a/ndctl/ndctl.h b/ndctl/ndctl.h index 008f81cdeb9f..426708e1fd9b 100644 --- a/ndctl/ndctl.h +++ b/ndctl/ndctl.h @@ -263,6 +263,7 @@ struct nd_cmd_pkg { #define NVDIMM_FAMILY_HPE2 2 #define NVDIMM_FAMILY_MSFT 3 #define NVDIMM_FAMILY_HYPERV 4 +#define NVDIMM_FAMILY_PAPR_SCM 5 #define ND_IOCTL_CALL _IOWR(ND_IOCTL, ND_CMD_CALL,\ struct nd_cmd_pkg) -- 2.24.1 _______________________________________________ Linux-nvdimm mailing list -- [email protected] To unsubscribe send an email to [email protected]
