| Message ID | 20230622035126.4130151-16-terry.bowman@amd.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | cxl/pci: Add support for RCH RAS error handling | expand |
On Wed, 21 Jun 2023 22:51:14 -0500 Terry Bowman <terry.bowman@amd.com> wrote: > From: Robert Richter <rrichter@amd.com> > > CXL capabilities are stored in the Component Registers. To use them, > the specific I/O ranges of the capabilities must be determined by > probing the registers. For this, the whole Component Register range > needs to be mapped temporarily to detect the offset and length of a > capability range. > > In order to use more than one capability of a component (e.g. RAS and > HDM) the Component Register are probed and its mappings created > multiple times. This also causes overlapping I/O ranges as the whole > Component Register range must be mapped again while a capability's I/O > range is already mapped. > > Different capabilities cannot be setup at the same time. E.g. the RAS > capability must be made available as soon as the PCI driver is bound, > the HDM decoder is setup later during port enumeration. Moreover, > during early setup it is still unknown if a certain capability is > needed. A central capability setup is therefore not possible, > capabilities must be individually enabled once needed during > initialization. > > To avoid a duplicate register probe and overlapping I/O mappings, only > probe the Component Registers one time and store the Component > Register mapping in struct port. The stored mappings can be used later > to iomap the capability register range when enabling the capability, > which will be implemented in a follow-on patch. > > Signed-off-by: Robert Richter <rrichter@amd.com> > Signed-off-by: Terry Bowman <terry.bowman@amd.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
On 6/21/23 20:51, Terry Bowman wrote: > From: Robert Richter <rrichter@amd.com> > > CXL capabilities are stored in the Component Registers. To use them, > the specific I/O ranges of the capabilities must be determined by > probing the registers. For this, the whole Component Register range > needs to be mapped temporarily to detect the offset and length of a > capability range. > > In order to use more than one capability of a component (e.g. RAS and > HDM) the Component Register are probed and its mappings created > multiple times. This also causes overlapping I/O ranges as the whole > Component Register range must be mapped again while a capability's I/O > range is already mapped. > > Different capabilities cannot be setup at the same time. E.g. the RAS > capability must be made available as soon as the PCI driver is bound, > the HDM decoder is setup later during port enumeration. Moreover, > during early setup it is still unknown if a certain capability is > needed. A central capability setup is therefore not possible, > capabilities must be individually enabled once needed during > initialization. > > To avoid a duplicate register probe and overlapping I/O mappings, only > probe the Component Registers one time and store the Component > Register mapping in struct port. The stored mappings can be used later > to iomap the capability register range when enabling the capability, > which will be implemented in a follow-on patch. > > Signed-off-by: Robert Richter <rrichter@amd.com> > Signed-off-by: Terry Bowman <terry.bowman@amd.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> > --- > drivers/cxl/core/port.c | 26 ++++++++++++++++++++++++++ > drivers/cxl/cxl.h | 2 ++ > 2 files changed, 28 insertions(+) > > diff --git a/drivers/cxl/core/port.c b/drivers/cxl/core/port.c > index 679226023f0c..2e239fd33df9 100644 > --- a/drivers/cxl/core/port.c > +++ b/drivers/cxl/core/port.c > @@ -688,6 +688,28 @@ static struct cxl_port *cxl_port_alloc(struct device *uport_dev, > return ERR_PTR(rc); > } > > +static int cxl_setup_comp_regs(struct device *dev, struct cxl_register_map *map, > + resource_size_t component_reg_phys) > +{ > + if (component_reg_phys == CXL_RESOURCE_NONE) > + return 0; > + > + memset(map, 0, sizeof(*map)); > + map->dev = dev; > + map->reg_type = CXL_REGLOC_RBI_COMPONENT; > + map->resource = component_reg_phys; > + map->max_size = CXL_COMPONENT_REG_BLOCK_SIZE; > + > + return cxl_setup_regs(map); > +} > + > +static inline int cxl_port_setup_regs(struct cxl_port *port, > + resource_size_t component_reg_phys) > +{ > + return cxl_setup_comp_regs(&port->dev, &port->comp_map, > + component_reg_phys); > +} > + > static struct cxl_port *__devm_cxl_add_port(struct device *host, > struct device *uport_dev, > resource_size_t component_reg_phys, > @@ -711,6 +733,10 @@ static struct cxl_port *__devm_cxl_add_port(struct device *host, > if (rc) > goto err; > > + rc = cxl_port_setup_regs(port, component_reg_phys); > + if (rc) > + goto err; > + > rc = device_add(dev); > if (rc) > goto err; > diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h > index fe95f08acb69..37fa5b565362 100644 > --- a/drivers/cxl/cxl.h > +++ b/drivers/cxl/cxl.h > @@ -547,6 +547,7 @@ struct cxl_dax_region { > * @regions: cxl_region_ref instances, regions mapped by this port > * @parent_dport: dport that points to this port in the parent > * @decoder_ida: allocator for decoder ids > + * @comp_map: component register capability mappings > * @nr_dports: number of entries in @dports > * @hdm_end: track last allocated HDM decoder instance for allocation ordering > * @commit_end: cursor to track highest committed decoder for commit ordering > @@ -566,6 +567,7 @@ struct cxl_port { > struct xarray regions; > struct cxl_dport *parent_dport; > struct ida decoder_ida; > + struct cxl_register_map comp_map; > int nr_dports; > int hdm_end; > int commit_end;
diff --git a/drivers/cxl/core/port.c b/drivers/cxl/core/port.c index 679226023f0c..2e239fd33df9 100644 --- a/drivers/cxl/core/port.c +++ b/drivers/cxl/core/port.c @@ -688,6 +688,28 @@ static struct cxl_port *cxl_port_alloc(struct device *uport_dev, return ERR_PTR(rc); } +static int cxl_setup_comp_regs(struct device *dev, struct cxl_register_map *map, + resource_size_t component_reg_phys) +{ + if (component_reg_phys == CXL_RESOURCE_NONE) + return 0; + + memset(map, 0, sizeof(*map)); + map->dev = dev; + map->reg_type = CXL_REGLOC_RBI_COMPONENT; + map->resource = component_reg_phys; + map->max_size = CXL_COMPONENT_REG_BLOCK_SIZE; + + return cxl_setup_regs(map); +} + +static inline int cxl_port_setup_regs(struct cxl_port *port, + resource_size_t component_reg_phys) +{ + return cxl_setup_comp_regs(&port->dev, &port->comp_map, + component_reg_phys); +} + static struct cxl_port *__devm_cxl_add_port(struct device *host, struct device *uport_dev, resource_size_t component_reg_phys, @@ -711,6 +733,10 @@ static struct cxl_port *__devm_cxl_add_port(struct device *host, if (rc) goto err; + rc = cxl_port_setup_regs(port, component_reg_phys); + if (rc) + goto err; + rc = device_add(dev); if (rc) goto err; diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h index fe95f08acb69..37fa5b565362 100644 --- a/drivers/cxl/cxl.h +++ b/drivers/cxl/cxl.h @@ -547,6 +547,7 @@ struct cxl_dax_region { * @regions: cxl_region_ref instances, regions mapped by this port * @parent_dport: dport that points to this port in the parent * @decoder_ida: allocator for decoder ids + * @comp_map: component register capability mappings * @nr_dports: number of entries in @dports * @hdm_end: track last allocated HDM decoder instance for allocation ordering * @commit_end: cursor to track highest committed decoder for commit ordering @@ -566,6 +567,7 @@ struct cxl_port { struct xarray regions; struct cxl_dport *parent_dport; struct ida decoder_ida; + struct cxl_register_map comp_map; int nr_dports; int hdm_end; int commit_end;