On Fri, Jul 26, 2024 at 05:05:55PM +0100, shiju.jose@xxxxxxxxxx wrote: > From: Shiju Jose <shiju.jose@xxxxxxxxxx> > > Memory ACPI RAS2 driver binds to the platform device add by the s/add/added/ > ACPI RAS2 table parser. > > Driver uses a PCC subspace for communicating with the ACPI compliant > platform to provide control of memory scrub parameters to the userspace > via the edac scrub. > > Get the scrub attr descriptors from the EDAC scrub and register with EDAC > RAS feature driver to expose sysfs scrub control attributes to the userspace. > For example scrub control for the RAS2 memory device is exposed in > /sys/bus/edac/devices/acpi_ras2_mem0/scrub/ > > Co-developed-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> > Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> > Signed-off-by: Shiju Jose <shiju.jose@xxxxxxxxxx> > --- > Documentation/scrub/edac-scrub.rst | 41 +++ > drivers/ras/Kconfig | 10 + > drivers/ras/Makefile | 1 + > drivers/ras/acpi_ras2.c | 415 +++++++++++++++++++++++++++++ > 4 files changed, 467 insertions(+) > create mode 100644 drivers/ras/acpi_ras2.c > > diff --git a/Documentation/scrub/edac-scrub.rst b/Documentation/scrub/edac-scrub.rst > index 7815d674f496..348f98091ac1 100644 > --- a/Documentation/scrub/edac-scrub.rst > +++ b/Documentation/scrub/edac-scrub.rst > @@ -72,3 +72,44 @@ root@localhost:~# cat /sys/bus/edac/devices/cxl_region0/scrub/enable_background > root@localhost:~# echo 0 > /sys/bus/edac/devices/cxl_region0/scrub/enable_background > root@localhost:~# cat /sys/bus/edac/devices/cxl_region0/scrub/enable_background > 0 > + > +2. RAS2 > +2.1 On demand scrubbing for a specific memory region. > +root@localhost:~# echo 0x120000 > /sys/bus/edac/devices/acpi_ras2_mem0/scrub/addr_range_base > +root@localhost:~# echo 0x150000 > /sys/bus/edac/devices/acpi_ras2_mem0/scrub/addr_range_size > +root@localhost:~# cat /sys/bus/edac/devices/acpi_ras2_mem0/scrub/min_cycle_duration > +1 > +root@localhost:~# cat /sys/bus/edac/devices/acpi_ras2_mem0/scrub/max_cycle_duration > +24 > +root@localhost:~# cat /sys/bus/edac/devices/acpi_ras2_mem0/scrub/current_cycle_duration > +10 > +root@localhost:~# echo 15 > /sys/bus/edac/devices/acpi_ras2_mem0/scrub/current_cycle_duration > +root@localhost:~# echo 1 > /sys/bus/edac/devices/acpi_ras2_mem0/scrub/enable_on_demand > +root@localhost:~# cat /sys/bus/edac/devices/acpi_ras2_mem0/scrub/enable_on_demand > +1 > +root@localhost:~# cat /sys/bus/edac/devices/acpi_ras2_mem0/scrub/current_cycle_duration > +15 > +root@localhost:~# cat /sys/bus/edac/devices/acpi_ras2_mem0/scrub/addr_range_base > +0x120000 > +root@localhost:~# cat //sys/bus/edac/devices/acpi_ras2_mem0/scrub/addr_range_size > +0x150000 > +root@localhost:~# echo 0 > /sys/bus/edac/devices/acpi_ras2_mem0/scrub/enable_on_demand > +root@localhost:~# cat /sys/bus/edac/devices/acpi_ras2_mem0/scrub/enable_on_demand > +0 > + > +2.2 Background scrubbing the entire memory > +root@localhost:~# cat /sys/bus/edac/devices/acpi_ras2_mem0/scrub/min_cycle_duration > +1 > +root@localhost:~# cat /sys/bus/edac/devices/acpi_ras2_mem0/scrub/max_cycle_duration > +24 > +root@localhost:~# cat /sys/bus/edac/devices/acpi_ras2_mem0/scrub/current_cycle_duration > +10 > +root@localhost:~# cat /sys/bus/edac/devices/acpi_ras2_mem0/enable_background > +0 > +root@localhost:~# echo 3 > /sys/bus/edac/devices/acpi_ras2_mem0/scrub/current_cycle_duration > +root@localhost:~# echo 1 > /sys/bus/edac/devices/acpi_ras2_mem0/enable_background > +root@localhost:~# cat /sys/bus/edac/devices/acpi_ras2_mem0/enable_background > +1 > +root@localhost:~# cat /sys/bus/edac/devices/acpi_ras2_mem0/scrub/current_cycle_duration > +3 > +root@localhost:~# echo 0 > /sys/bus/edac/devices/acpi_ras2_mem0/enable_background > diff --git a/drivers/ras/Kconfig b/drivers/ras/Kconfig > index fc4f4bb94a4c..a2635017d80d 100644 > --- a/drivers/ras/Kconfig > +++ b/drivers/ras/Kconfig > @@ -46,4 +46,14 @@ config RAS_FMPM > Memory will be retired during boot time and run time depending on > platform-specific policies. > > +config MEM_ACPI_RAS2 > + tristate "Memory ACPI RAS2 driver" > + depends on ACPI_RAS2 > + depends on EDAC > + help > + The driver binds to the platform device added by the ACPI RAS2 > + table parser. Use a PCC channel subspace for communicating with > + the ACPI compliant platform to provide control of memory scrub > + parameters to the user via the edac scrub. > + > endif > diff --git a/drivers/ras/Makefile b/drivers/ras/Makefile > index 11f95d59d397..a0e6e903d6b0 100644 > --- a/drivers/ras/Makefile > +++ b/drivers/ras/Makefile > @@ -2,6 +2,7 @@ > obj-$(CONFIG_RAS) += ras.o > obj-$(CONFIG_DEBUG_FS) += debugfs.o > obj-$(CONFIG_RAS_CEC) += cec.o > +obj-$(CONFIG_MEM_ACPI_RAS2) += acpi_ras2.o > > obj-$(CONFIG_RAS_FMPM) += amd/fmpm.o > obj-y += amd/atl/ > diff --git a/drivers/ras/acpi_ras2.c b/drivers/ras/acpi_ras2.c > new file mode 100644 > index 000000000000..b2381d5b37d0 > --- /dev/null > +++ b/drivers/ras/acpi_ras2.c > @@ -0,0 +1,415 @@ > +// SPDX-License-Identifier: GPL-2.0-or-later > +/* > + * ACPI RAS2 memory driver > + * > + * Copyright (c) 2024 HiSilicon Limited. > + * > + */ > + > +#define pr_fmt(fmt) "MEMORY ACPI RAS2: " fmt > + > +#include <linux/edac_ras_feature.h> > +#include <linux/platform_device.h> > +#include <acpi/ras2_acpi.h> > + > +#define RAS2_DEV_NUM_RAS_FEATURES 1 > + > +#define RAS2_SUPPORT_HW_PARTOL_SCRUB BIT(0) > +#define RAS2_TYPE_PATROL_SCRUB 0x0000 > + > +#define RAS2_GET_PATROL_PARAMETERS 0x01 > +#define RAS2_START_PATROL_SCRUBBER 0x02 > +#define RAS2_STOP_PATROL_SCRUBBER 0x03 > + > +#define RAS2_PATROL_SCRUB_SCHRS_IN_MASK GENMASK(15, 8) > +#define RAS2_PATROL_SCRUB_EN_BACKGROUND BIT(0) > +#define RAS2_PATROL_SCRUB_SCHRS_OUT_MASK GENMASK(7, 0) > +#define RAS2_PATROL_SCRUB_MIN_SCHRS_OUT_MASK GENMASK(15, 8) > +#define RAS2_PATROL_SCRUB_MAX_SCHRS_OUT_MASK GENMASK(23, 16) > +#define RAS2_PATROL_SCRUB_FLAG_SCRUBBER_RUNNING BIT(0) > + > +#define RAS2_SCRUB_NAME_LEN 128 > + > +struct acpi_ras2_ps_shared_mem { > + struct acpi_ras2_shared_memory common; > + struct acpi_ras2_patrol_scrub_parameter params; > +}; > + > +static int ras2_is_patrol_scrub_support(struct ras2_scrub_ctx *ras2_ctx) > +{ > + struct acpi_ras2_shared_memory __iomem *common = (void *) > + ras2_ctx->pcc_subspace->pcc_comm_addr; > + > + guard(mutex)(&ras2_ctx->lock); > + common->set_capabilities[0] = 0; > + > + return common->features[0] & RAS2_SUPPORT_HW_PARTOL_SCRUB; > +} > + > +static int ras2_update_patrol_scrub_params_cache(struct ras2_scrub_ctx *ras2_ctx) > +{ > + struct acpi_ras2_ps_shared_mem __iomem *ps_sm = (void *) > + ras2_ctx->pcc_subspace->pcc_comm_addr; > + int ret; > + > + ps_sm->common.set_capabilities[0] = RAS2_SUPPORT_HW_PARTOL_SCRUB; > + ps_sm->params.patrol_scrub_command = RAS2_GET_PATROL_PARAMETERS; > + > + ret = ras2_send_pcc_cmd(ras2_ctx, RAS2_PCC_CMD_EXEC); > + if (ret) { > + dev_err(ras2_ctx->dev, "failed to read parameters\n"); > + return ret; > + } > + > + ras2_ctx->min_scrub_cycle = FIELD_GET(RAS2_PATROL_SCRUB_MIN_SCHRS_OUT_MASK, > + ps_sm->params.scrub_params_out); > + ras2_ctx->max_scrub_cycle = FIELD_GET(RAS2_PATROL_SCRUB_MAX_SCHRS_OUT_MASK, > + ps_sm->params.scrub_params_out); > + if (!ras2_ctx->bg) { > + ras2_ctx->base = ps_sm->params.actual_address_range[0]; > + ras2_ctx->size = ps_sm->params.actual_address_range[1]; > + } > + ras2_ctx->scrub_cycle_secs = FIELD_GET(RAS2_PATROL_SCRUB_SCHRS_OUT_MASK, > + ps_sm->params.scrub_params_out); > + > + return 0; > +} > + > +/* Context - lock must be held */ > +static int ras2_get_patrol_scrub_running(struct ras2_scrub_ctx *ras2_ctx, > + bool *running) > +{ > + struct acpi_ras2_ps_shared_mem __iomem *ps_sm = (void *) > + ras2_ctx->pcc_subspace->pcc_comm_addr; > + int ret; > + > + ps_sm->common.set_capabilities[0] = RAS2_SUPPORT_HW_PARTOL_SCRUB; > + ps_sm->params.patrol_scrub_command = RAS2_GET_PATROL_PARAMETERS; > + > + ret = ras2_send_pcc_cmd(ras2_ctx, RAS2_PCC_CMD_EXEC); > + if (ret) { > + dev_err(ras2_ctx->dev, "failed to read parameters\n"); > + return ret; > + } > + > + *running = ps_sm->params.flags & RAS2_PATROL_SCRUB_FLAG_SCRUBBER_RUNNING; > + > + return 0; > +} > + > +static int ras2_hw_scrub_read_min_scrub_cycle(struct device *dev, void *drv_data, > + u32 *min) > +{ > + struct ras2_scrub_ctx *ras2_ctx = drv_data; > + > + *min = ras2_ctx->min_scrub_cycle; > + > + return 0; > +} > + > +static int ras2_hw_scrub_read_max_scrub_cycle(struct device *dev, void *drv_data, > + u32 *max) > +{ > + struct ras2_scrub_ctx *ras2_ctx = drv_data; > + > + *max = ras2_ctx->max_scrub_cycle; > + > + return 0; > +} > + > +static int ras2_hw_scrub_cycle_read(struct device *dev, void *drv_data, > + u32 *scrub_cycle_secs) > +{ > + struct ras2_scrub_ctx *ras2_ctx = drv_data; > + > + *scrub_cycle_secs = ras2_ctx->scrub_cycle_secs; > + > + return 0; > +} > + > +static int ras2_hw_scrub_cycle_write(struct device *dev, void *drv_data, > + u32 scrub_cycle_secs) > +{ > + struct ras2_scrub_ctx *ras2_ctx = drv_data; > + bool running; > + int ret; > + > + guard(mutex)(&ras2_ctx->lock); > + ret = ras2_get_patrol_scrub_running(ras2_ctx, &running); > + if (ret) > + return ret; > + > + if (running) > + return -EBUSY; > + > + if (scrub_cycle_secs < ras2_ctx->min_scrub_cycle || > + scrub_cycle_secs > ras2_ctx->max_scrub_cycle) > + return -EINVAL; > + > + ras2_ctx->scrub_cycle_secs = scrub_cycle_secs; > + > + return 0; > +} > + > +static int ras2_hw_scrub_read_range(struct device *dev, void *drv_data, u64 *base, u64 *size) > +{ > + struct ras2_scrub_ctx *ras2_ctx = drv_data; > + > + /* > + * When BG scrubbing is enabled the actual address range is not valid. > + * Return -EBUSY now unless findout a method to retrieve actual full PA range. > + */ > + if (ras2_ctx->bg) > + return -EBUSY; > + > + *base = ras2_ctx->base; > + *size = ras2_ctx->size; > + > + return 0; > +} > + > +static int ras2_hw_scrub_write_range(struct device *dev, void *drv_data, u64 base, u64 size) > +{ > + struct ras2_scrub_ctx *ras2_ctx = drv_data; > + bool running; > + int ret; > + > + guard(mutex)(&ras2_ctx->lock); > + ret = ras2_get_patrol_scrub_running(ras2_ctx, &running); > + if (ret) > + return ret; > + > + if (running) > + return -EBUSY; > + > + if (!base || !size) { > + dev_warn(dev, "%s: Invalid address range, base=0x%llx size=0x%llx\n", > + __func__, base, size); > + return -EINVAL; > + } > + > + ras2_ctx->base = base; > + ras2_ctx->size = size; > + > + return 0; > +} > + > +static int ras2_hw_scrub_set_enabled_bg(struct device *dev, void *drv_data, bool enable) > +{ > + struct ras2_scrub_ctx *ras2_ctx = drv_data; > + struct acpi_ras2_ps_shared_mem __iomem *ps_sm = (void *) > + ras2_ctx->pcc_subspace->pcc_comm_addr; > + bool enabled; > + int ret; > + > + guard(mutex)(&ras2_ctx->lock); > + ps_sm->common.set_capabilities[0] = RAS2_SUPPORT_HW_PARTOL_SCRUB; > + ret = ras2_get_patrol_scrub_running(ras2_ctx, &enabled); We have a passed-in argument "enable", we have another local variable "enabled", will "running" be more accurate instead of "enabled"? The same as in ras2_hw_scrub_set_enabled_od() Fan > + if (ret) > + return ret; > + if (enable) { > + if (ras2_ctx->bg || enabled) > + return -EBUSY; > + ps_sm->params.requested_address_range[0] = 0; > + ps_sm->params.requested_address_range[1] = 0; > + ps_sm->params.scrub_params_in &= ~RAS2_PATROL_SCRUB_SCHRS_IN_MASK; > + ps_sm->params.scrub_params_in |= FIELD_PREP(RAS2_PATROL_SCRUB_SCHRS_IN_MASK, > + ras2_ctx->scrub_cycle_secs); > + ps_sm->params.patrol_scrub_command = RAS2_START_PATROL_SCRUBBER; > + } else { > + if (!ras2_ctx->bg) > + return -EPERM; > + if (!ras2_ctx->bg && enabled) > + return -EBUSY; > + ps_sm->params.patrol_scrub_command = RAS2_STOP_PATROL_SCRUBBER; > + } > + ps_sm->params.scrub_params_in &= ~RAS2_PATROL_SCRUB_EN_BACKGROUND; > + ps_sm->params.scrub_params_in |= FIELD_PREP(RAS2_PATROL_SCRUB_EN_BACKGROUND, > + enable); > + ret = ras2_send_pcc_cmd(ras2_ctx, RAS2_PCC_CMD_EXEC); > + if (ret) { > + dev_err(ras2_ctx->dev, "%s: failed to enable(%d) background scrubbing\n", > + __func__, enable); Similar suggestion as below. > + return ret; > + } > + if (enable) { > + ras2_ctx->bg = true; > + /* Update the cache to account for rounding of supplied parameters and similar */ > + ret = ras2_update_patrol_scrub_params_cache(ras2_ctx); > + } else { > + ret = ras2_update_patrol_scrub_params_cache(ras2_ctx); > + ras2_ctx->bg = false; > + } > + > + return ret; > +} > + > +static int ras2_hw_scrub_get_enabled_bg(struct device *dev, void *drv_data, bool *enabled) > +{ > + struct ras2_scrub_ctx *ras2_ctx = drv_data; > + > + *enabled = ras2_ctx->bg; > + > + return 0; > +} > + > +static int ras2_hw_scrub_set_enabled_od(struct device *dev, void *drv_data, bool enable) > +{ > + struct ras2_scrub_ctx *ras2_ctx = drv_data; > + struct acpi_ras2_ps_shared_mem __iomem *ps_sm = (void *) > + ras2_ctx->pcc_subspace->pcc_comm_addr; > + bool enabled; > + int ret; > + > + guard(mutex)(&ras2_ctx->lock); > + ps_sm->common.set_capabilities[0] = RAS2_SUPPORT_HW_PARTOL_SCRUB; > + if (ras2_ctx->bg) > + return -EBUSY; > + ret = ras2_get_patrol_scrub_running(ras2_ctx, &enabled); > + if (ret) > + return ret; > + if (enable) { > + if (!ras2_ctx->base || !ras2_ctx->size) { > + dev_warn(ras2_ctx->dev, > + "%s: Invalid address range, base=0x%llx " > + "size=0x%llx\n", __func__, > + ras2_ctx->base, ras2_ctx->size); > + return -ERANGE; > + } > + if (enabled) > + return -EBUSY; > + ps_sm->params.scrub_params_in &= ~RAS2_PATROL_SCRUB_SCHRS_IN_MASK; > + ps_sm->params.scrub_params_in |= FIELD_PREP(RAS2_PATROL_SCRUB_SCHRS_IN_MASK, > + ras2_ctx->scrub_cycle_secs); > + ps_sm->params.requested_address_range[0] = ras2_ctx->base; > + ps_sm->params.requested_address_range[1] = ras2_ctx->size; > + ps_sm->params.scrub_params_in &= ~RAS2_PATROL_SCRUB_EN_BACKGROUND; > + ps_sm->params.patrol_scrub_command = RAS2_START_PATROL_SCRUBBER; > + } else { > + if (!enabled) > + return 0; > + ps_sm->params.patrol_scrub_command = RAS2_STOP_PATROL_SCRUBBER; > + } > + > + ret = ras2_send_pcc_cmd(ras2_ctx, RAS2_PCC_CMD_EXEC); > + if (ret) { > + dev_err(ras2_ctx->dev, "failed to enable(%d) the demand scrubbing\n", enable); Can we improve the messaging as below to make it clearer? dev_err(ras2_ctx->dev, "failed to %s the demand scrubbing\n", enable ? "enable":"disable"); Fan > + return ret; > + } > + > + return ras2_update_patrol_scrub_params_cache(ras2_ctx); > +} > + > +static int ras2_hw_scrub_get_enabled_od(struct device *dev, void *drv_data, bool *enabled) > +{ > + struct ras2_scrub_ctx *ras2_ctx = drv_data; > + > + guard(mutex)(&ras2_ctx->lock); > + if (ras2_ctx->bg) { > + *enabled = false; > + return 0; > + } > + > + return ras2_get_patrol_scrub_running(ras2_ctx, enabled); > +} > + > +static int ras2_hw_scrub_get_name(struct device *dev, void *drv_data, char *name) > +{ > + struct ras2_scrub_ctx *ras2_ctx = drv_data; > + > + return sysfs_emit(name, "acpi_ras2_mem%d_scrub\n", ras2_ctx->id); > +} > + > +static const struct edac_scrub_ops ras2_scrub_ops = { > + .read_range = ras2_hw_scrub_read_range, > + .write_range = ras2_hw_scrub_write_range, > + .get_enabled_bg = ras2_hw_scrub_get_enabled_bg, > + .set_enabled_bg = ras2_hw_scrub_set_enabled_bg, > + .get_enabled_od = ras2_hw_scrub_get_enabled_od, > + .set_enabled_od = ras2_hw_scrub_set_enabled_od, > + .get_name = ras2_hw_scrub_get_name, > + .min_cycle_read = ras2_hw_scrub_read_min_scrub_cycle, > + .max_cycle_read = ras2_hw_scrub_read_max_scrub_cycle, > + .cycle_duration_read = ras2_hw_scrub_cycle_read, > + .cycle_duration_write = ras2_hw_scrub_cycle_write, > +}; > + > +static DEFINE_IDA(ras2_ida); > + > +static void ida_release(void *ctx) > +{ > + struct ras2_scrub_ctx *ras2_ctx = ctx; > + > + ida_free(&ras2_ida, ras2_ctx->id); > +} > + > +static int ras2_probe(struct platform_device *pdev) > +{ > + struct edac_ras_feature ras_features[RAS2_DEV_NUM_RAS_FEATURES]; > + char scrub_name[RAS2_SCRUB_NAME_LEN]; > + struct ras2_scrub_ctx *ras2_ctx; > + int num_ras_features = 0; > + int ret, id; > + > + /* RAS2 PCC Channel and Scrub specific context */ > + ras2_ctx = devm_kzalloc(&pdev->dev, sizeof(*ras2_ctx), GFP_KERNEL); > + if (!ras2_ctx) > + return -ENOMEM; > + > + ras2_ctx->dev = &pdev->dev; > + mutex_init(&ras2_ctx->lock); > + > + ret = devm_ras2_register_pcc_channel(&pdev->dev, ras2_ctx, > + *((int *)dev_get_platdata(&pdev->dev))); > + if (ret < 0) { > + dev_dbg(ras2_ctx->dev, > + "failed to register pcc channel ret=%d\n", ret); > + return ret; > + } > + if (!ras2_is_patrol_scrub_support(ras2_ctx)) > + return -EOPNOTSUPP; > + > + ret = ras2_update_patrol_scrub_params_cache(ras2_ctx); > + if (ret) > + return ret; > + > + id = ida_alloc(&ras2_ida, GFP_KERNEL); > + if (id < 0) > + return id; > + > + ras2_ctx->id = id; > + > + ret = devm_add_action_or_reset(&pdev->dev, ida_release, ras2_ctx); > + if (ret < 0) > + return ret; > + > + snprintf(scrub_name, sizeof(scrub_name), "acpi_ras2_mem%d", > + ras2_ctx->id); > + > + ras_features[num_ras_features].feat = RAS_FEAT_SCRUB; > + ras_features[num_ras_features].scrub_ops = &ras2_scrub_ops; > + ras_features[num_ras_features].scrub_ctx = ras2_ctx; > + num_ras_features++; > + > + return edac_ras_dev_register(&pdev->dev, scrub_name, NULL, > + num_ras_features, ras_features); > +} > + > +static const struct platform_device_id ras2_id_table[] = { > + { .name = "acpi_ras2", }, > + { } > +}; > +MODULE_DEVICE_TABLE(platform, ras2_id_table); > + > +static struct platform_driver ras2_driver = { > + .probe = ras2_probe, > + .driver = { > + .name = "acpi_ras2", > + }, > + .id_table = ras2_id_table, > +}; > +module_driver(ras2_driver, platform_driver_register, platform_driver_unregister); > + > +MODULE_IMPORT_NS(ACPI_RAS2); > +MODULE_DESCRIPTION("ACPI RAS2 memory driver"); > +MODULE_LICENSE("GPL"); > -- > 2.34.1 >