diff options
| -rw-r--r-- | drivers/acpi/Kconfig | 3 | ||||
| -rw-r--r-- | drivers/acpi/acpi_platform.c | 2 | ||||
| -rw-r--r-- | drivers/acpi/glue.c | 5 | ||||
| -rw-r--r-- | drivers/acpi/scan.c | 35 | ||||
| -rw-r--r-- | include/acpi/acpi_bus.h | 37 | ||||
| -rw-r--r-- | include/linux/acpi.h | 5 |
6 files changed, 85 insertions, 2 deletions
diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig index ab2cbb5..212735f 100644 --- a/drivers/acpi/Kconfig +++ b/drivers/acpi/Kconfig @@ -54,6 +54,9 @@ config ACPI_GENERIC_GSI config ACPI_SYSTEM_POWER_STATES_SUPPORT bool +config ACPI_CCA_REQUIRED + bool + config ACPI_SLEEP bool depends on SUSPEND || HIBERNATION diff --git a/drivers/acpi/acpi_platform.c b/drivers/acpi/acpi_platform.c index 4bf7559..06a67d5 100644 --- a/drivers/acpi/acpi_platform.c +++ b/drivers/acpi/acpi_platform.c @@ -103,7 +103,7 @@ struct platform_device *acpi_create_platform_device(struct acpi_device *adev) pdevinfo.res = resources; pdevinfo.num_res = count; pdevinfo.fwnode = acpi_fwnode_handle(adev); - pdevinfo.dma_mask = DMA_BIT_MASK(32); + pdevinfo.dma_mask = acpi_check_dma(adev, NULL) ? DMA_BIT_MASK(32) : 0; pdev = platform_device_register_full(&pdevinfo); if (IS_ERR(pdev)) dev_err(&adev->dev, "platform device creation failed: %ld\n", diff --git a/drivers/acpi/glue.c b/drivers/acpi/glue.c index 39c485b..b9657af 100644 --- a/drivers/acpi/glue.c +++ b/drivers/acpi/glue.c @@ -13,6 +13,7 @@ #include <linux/slab.h> #include <linux/rwsem.h> #include <linux/acpi.h> +#include <linux/dma-mapping.h> #include "internal.h" @@ -167,6 +168,7 @@ int acpi_bind_one(struct device *dev, struct acpi_device *acpi_dev) struct list_head *physnode_list; unsigned int node_id; int retval = -EINVAL; + bool coherent; if (has_acpi_companion(dev)) { if (acpi_dev) { @@ -223,6 +225,9 @@ int acpi_bind_one(struct device *dev, struct acpi_device *acpi_dev) if (!has_acpi_companion(dev)) ACPI_COMPANION_SET(dev, acpi_dev); + if (acpi_check_dma(acpi_dev, &coherent)) + arch_setup_dma_ops(dev, 0, 0, NULL, coherent); + acpi_physnode_link_name(physical_node_name, node_id); retval = sysfs_create_link(&acpi_dev->dev.kobj, &dev->kobj, physical_node_name); diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index 0a09991..67509b2 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -11,6 +11,7 @@ #include <linux/kthread.h> #include <linux/dmi.h> #include <linux/nls.h> +#include <linux/dma-mapping.h> #include <asm/pgtable.h> @@ -2111,6 +2112,39 @@ void acpi_free_pnp_ids(struct acpi_device_pnp *pnp) kfree(pnp->unique_id); } +static void acpi_init_coherency(struct acpi_device *adev) +{ + unsigned long long cca = 0; + acpi_status status; + struct acpi_device *parent = adev->parent; + + if (parent && parent->flags.cca_seen) { + /* + * From ACPI spec, OSPM will ignore _CCA if an ancestor + * already saw one. + */ + adev->flags.cca_seen = 1; + cca = parent->flags.coherent_dma; + } else { + status = acpi_evaluate_integer(adev->handle, "_CCA", + NULL, &cca); + if (ACPI_SUCCESS(status)) + adev->flags.cca_seen = 1; + else if (!IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED)) + /* + * If architecture does not specify that _CCA is + * required for DMA-able devices (e.g. x86), + * we default to _CCA=1. + */ + cca = 1; + else + acpi_handle_debug(adev->handle, + "ACPI device is missing _CCA.\n"); + } + + adev->flags.coherent_dma = cca; +} + void acpi_init_device_object(struct acpi_device *device, acpi_handle handle, int type, unsigned long long sta) { @@ -2129,6 +2163,7 @@ void acpi_init_device_object(struct acpi_device *device, acpi_handle handle, device->flags.visited = false; device_initialize(&device->dev); dev_set_uevent_suppress(&device->dev, true); + acpi_init_coherency(device); } void acpi_device_add_finalize(struct acpi_device *device) diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h index da07997..54df54d 100644 --- a/include/acpi/acpi_bus.h +++ b/include/acpi/acpi_bus.h @@ -209,7 +209,9 @@ struct acpi_device_flags { u32 hotplug_notify:1; u32 is_dock_station:1; u32 of_compatible_ok:1; - u32 reserved:22; + u32 coherent_dma:1; + u32 cca_seen:1; + u32 reserved:20; }; /* File System */ @@ -381,6 +383,39 @@ struct acpi_device { void (*remove)(struct acpi_device *); }; +static inline bool acpi_check_dma(struct acpi_device *adev, bool *coherent) +{ + bool ret = false; + + if (!adev) + return ret; + + /** + * Currently, we only support _CCA=1 (i.e. coherent_dma=1) + * This should be equivalent to specifyig dma-coherent for + * a device in OF. + * + * For the case when _CCA=0 (i.e. coherent_dma=0 && cca_seen=1), + * There are two cases: + * case 1. Do not support and disable DMA. + * case 2. Support but rely on arch-specific cache maintenance for + * non-coherence DMA operations. + * Currently, we implement case 1 above. + * + * For the case when _CCA is missing (i.e. cca_seen=0) and + * platform specifies ACPI_CCA_REQUIRED, we do not support DMA, + * and fallback to arch-specific default handling. + * + * See acpi_init_coherency() for more info. + */ + if (adev->flags.coherent_dma) { + ret = true; + if (coherent) + *coherent = adev->flags.coherent_dma; + } + return ret; +} + static inline bool is_acpi_node(struct fwnode_handle *fwnode) { return fwnode && fwnode->type == FWNODE_ACPI; diff --git a/include/linux/acpi.h b/include/linux/acpi.h index e4da5e3..d46a48c 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -569,6 +569,11 @@ static inline int acpi_device_modalias(struct device *dev, return -ENODEV; } +static inline bool acpi_check_dma(struct acpi_device *adev, bool *coherent) +{ + return false; +} + #define ACPI_PTR(_ptr) (NULL) #endif /* !CONFIG_ACPI */ |