diff options
| -rw-r--r-- | drivers/Makefile | 2 | ||||
| -rw-r--r-- | drivers/cxl/Kconfig | 4 | ||||
| -rw-r--r-- | drivers/cxl/Makefile | 2 | ||||
| -rw-r--r-- | drivers/cxl/core/Makefile | 1 | ||||
| -rw-r--r-- | drivers/cxl/core/suspend.c | 24 | ||||
| -rw-r--r-- | drivers/cxl/cxlmem.h | 11 | ||||
| -rw-r--r-- | drivers/cxl/mem.c | 22 | ||||
| -rw-r--r-- | include/linux/pm.h | 9 | ||||
| -rw-r--r-- | kernel/power/hibernate.c | 2 | ||||
| -rw-r--r-- | kernel/power/main.c | 5 | ||||
| -rw-r--r-- | kernel/power/suspend.c | 3 |
11 files changed, 79 insertions, 6 deletions
diff --git a/drivers/Makefile b/drivers/Makefile index 020780b6b4d2..f735c4955143 100644 --- a/drivers/Makefile +++ b/drivers/Makefile @@ -72,9 +72,9 @@ obj-$(CONFIG_PARPORT) += parport/ obj-y += base/ block/ misc/ mfd/ nfc/ obj-$(CONFIG_LIBNVDIMM) += nvdimm/ obj-$(CONFIG_DAX) += dax/ -obj-$(CONFIG_CXL_BUS) += cxl/ obj-$(CONFIG_DMA_SHARED_BUFFER) += dma-buf/ obj-$(CONFIG_NUBUS) += nubus/ +obj-y += cxl/ obj-y += macintosh/ obj-y += scsi/ obj-y += nvme/ diff --git a/drivers/cxl/Kconfig b/drivers/cxl/Kconfig index b88ab956bb7c..f64e3984689f 100644 --- a/drivers/cxl/Kconfig +++ b/drivers/cxl/Kconfig @@ -98,4 +98,8 @@ config CXL_PORT default CXL_BUS tristate +config CXL_SUSPEND + def_bool y + depends on SUSPEND && CXL_MEM + endif diff --git a/drivers/cxl/Makefile b/drivers/cxl/Makefile index ce267ef11d93..a78270794150 100644 --- a/drivers/cxl/Makefile +++ b/drivers/cxl/Makefile @@ -1,5 +1,5 @@ # SPDX-License-Identifier: GPL-2.0 -obj-$(CONFIG_CXL_BUS) += core/ +obj-y += core/ obj-$(CONFIG_CXL_PCI) += cxl_pci.o obj-$(CONFIG_CXL_MEM) += cxl_mem.o obj-$(CONFIG_CXL_ACPI) += cxl_acpi.o diff --git a/drivers/cxl/core/Makefile b/drivers/cxl/core/Makefile index 6d37cd78b151..9d35085d25af 100644 --- a/drivers/cxl/core/Makefile +++ b/drivers/cxl/core/Makefile @@ -1,5 +1,6 @@ # SPDX-License-Identifier: GPL-2.0 obj-$(CONFIG_CXL_BUS) += cxl_core.o +obj-$(CONFIG_CXL_SUSPEND) += suspend.o ccflags-y += -I$(srctree)/drivers/cxl cxl_core-y := port.o diff --git a/drivers/cxl/core/suspend.c b/drivers/cxl/core/suspend.c new file mode 100644 index 000000000000..a5984d96ea1d --- /dev/null +++ b/drivers/cxl/core/suspend.c @@ -0,0 +1,24 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Copyright(c) 2022 Intel Corporation. All rights reserved. */ +#include <linux/atomic.h> +#include <linux/export.h> +#include "cxlmem.h" + +static atomic_t mem_active; + +bool cxl_mem_active(void) +{ + return atomic_read(&mem_active) != 0; +} + +void cxl_mem_active_inc(void) +{ + atomic_inc(&mem_active); +} +EXPORT_SYMBOL_NS_GPL(cxl_mem_active_inc, CXL); + +void cxl_mem_active_dec(void) +{ + atomic_dec(&mem_active); +} +EXPORT_SYMBOL_NS_GPL(cxl_mem_active_dec, CXL); diff --git a/drivers/cxl/cxlmem.h b/drivers/cxl/cxlmem.h index 243dd86a8b46..7235d2f976e5 100644 --- a/drivers/cxl/cxlmem.h +++ b/drivers/cxl/cxlmem.h @@ -353,6 +353,17 @@ int cxl_mem_create_range_info(struct cxl_dev_state *cxlds); struct cxl_dev_state *cxl_dev_state_create(struct device *dev); void set_exclusive_cxl_commands(struct cxl_dev_state *cxlds, unsigned long *cmds); void clear_exclusive_cxl_commands(struct cxl_dev_state *cxlds, unsigned long *cmds); +#ifdef CONFIG_CXL_SUSPEND +void cxl_mem_active_inc(void); +void cxl_mem_active_dec(void); +#else +static inline void cxl_mem_active_inc(void) +{ +} +static inline void cxl_mem_active_dec(void) +{ +} +#endif struct cxl_hdm { struct cxl_component_regs regs; diff --git a/drivers/cxl/mem.c b/drivers/cxl/mem.c index 43e73d259207..1bd2e0b67f59 100644 --- a/drivers/cxl/mem.c +++ b/drivers/cxl/mem.c @@ -138,6 +138,11 @@ out: return retval; } +static void enable_suspend(void *data) +{ + cxl_mem_active_dec(); +} + static int cxl_mem_probe(struct device *dev) { struct cxl_memdev *cxlmd = to_cxl_memdev(dev); @@ -194,7 +199,22 @@ static int cxl_mem_probe(struct device *dev) out: cxl_device_unlock(&parent_port->dev); put_device(&parent_port->dev); - return rc; + + /* + * The kernel may be operating out of CXL memory on this device, + * there is no spec defined way to determine whether this device + * preserves contents over suspend, and there is no simple way + * to arrange for the suspend image to avoid CXL memory which + * would setup a circular dependency between PCI resume and save + * state restoration. + * + * TODO: support suspend when all the regions this device is + * hosting are locked and covered by the system address map, + * i.e. platform firmware owns restoring the HDM configuration + * that it locked. + */ + cxl_mem_active_inc(); + return devm_add_action_or_reset(dev, enable_suspend, NULL); } static struct cxl_driver cxl_mem_driver = { diff --git a/include/linux/pm.h b/include/linux/pm.h index e65b3ab28377..7911c4c9a7be 100644 --- a/include/linux/pm.h +++ b/include/linux/pm.h @@ -36,6 +36,15 @@ static inline void pm_vt_switch_unregister(struct device *dev) } #endif /* CONFIG_VT_CONSOLE_SLEEP */ +#ifdef CONFIG_CXL_SUSPEND +bool cxl_mem_active(void); +#else +static inline bool cxl_mem_active(void) +{ + return false; +} +#endif + /* * Device power management */ diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index 938d5c78b421..20a66bf9f465 100644 --- a/kernel/power/hibernate.c +++ b/kernel/power/hibernate.c @@ -83,7 +83,7 @@ bool hibernation_available(void) { return nohibernate == 0 && !security_locked_down(LOCKDOWN_HIBERNATION) && - !secretmem_active(); + !secretmem_active() && !cxl_mem_active(); } /** diff --git a/kernel/power/main.c b/kernel/power/main.c index 7e646079fbeb..3e6be1c33e0b 100644 --- a/kernel/power/main.c +++ b/kernel/power/main.c @@ -127,7 +127,9 @@ static ssize_t mem_sleep_show(struct kobject *kobj, struct kobj_attribute *attr, char *s = buf; suspend_state_t i; - for (i = PM_SUSPEND_MIN; i < PM_SUSPEND_MAX; i++) + for (i = PM_SUSPEND_MIN; i < PM_SUSPEND_MAX; i++) { + if (i >= PM_SUSPEND_MEM && cxl_mem_active()) + continue; if (mem_sleep_states[i]) { const char *label = mem_sleep_states[i]; @@ -136,6 +138,7 @@ static ssize_t mem_sleep_show(struct kobject *kobj, struct kobj_attribute *attr, else s += sprintf(s, "%s ", label); } + } /* Convert the last space to a newline if needed. */ if (s != buf) diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c index 6fcdee7e87a5..827075944d28 100644 --- a/kernel/power/suspend.c +++ b/kernel/power/suspend.c @@ -236,7 +236,8 @@ EXPORT_SYMBOL_GPL(suspend_valid_only_mem); static bool sleep_state_supported(suspend_state_t state) { - return state == PM_SUSPEND_TO_IDLE || valid_state(state); + return state == PM_SUSPEND_TO_IDLE || + (valid_state(state) && !cxl_mem_active()); } static int platform_suspend_prepare(suspend_state_t state) |