diff options
Diffstat (limited to 'drivers/acpi/arm64/apmt.c')
| -rw-r--r-- | drivers/acpi/arm64/apmt.c | 178 |
1 files changed, 178 insertions, 0 deletions
diff --git a/drivers/acpi/arm64/apmt.c b/drivers/acpi/arm64/apmt.c new file mode 100644 index 000000000000..8cab69fa5d59 --- /dev/null +++ b/drivers/acpi/arm64/apmt.c @@ -0,0 +1,178 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * ARM APMT table support. + * Design document number: ARM DEN0117. + * + * Copyright (c) 2022, NVIDIA CORPORATION & AFFILIATES. + * + */ + +#define pr_fmt(fmt) "ACPI: APMT: " fmt + +#include <linux/acpi.h> +#include <linux/acpi_apmt.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/platform_device.h> + +#define DEV_NAME "arm-cs-arch-pmu" + +/* There can be up to 3 resources: page 0 and 1 address, and interrupt. */ +#define DEV_MAX_RESOURCE_COUNT 3 + +/* Root pointer to the mapped APMT table */ +static struct acpi_table_header *apmt_table; + +static int __init apmt_init_resources(struct resource *res, + struct acpi_apmt_node *node) +{ + int irq, trigger; + int num_res = 0; + + res[num_res].start = node->base_address0; + res[num_res].end = node->base_address0 + SZ_4K - 1; + res[num_res].flags = IORESOURCE_MEM; + + num_res++; + + res[num_res].start = node->base_address1; + res[num_res].end = node->base_address1 + SZ_4K - 1; + res[num_res].flags = IORESOURCE_MEM; + + num_res++; + + if (node->ovflw_irq != 0) { + trigger = (node->ovflw_irq_flags & ACPI_APMT_OVFLW_IRQ_FLAGS_MODE); + trigger = (trigger == ACPI_APMT_OVFLW_IRQ_FLAGS_MODE_LEVEL) ? + ACPI_LEVEL_SENSITIVE : ACPI_EDGE_SENSITIVE; + irq = acpi_register_gsi(NULL, node->ovflw_irq, trigger, + ACPI_ACTIVE_HIGH); + + if (irq <= 0) { + pr_warn("APMT could not register gsi hwirq %d\n", irq); + return num_res; + } + + res[num_res].start = irq; + res[num_res].end = irq; + res[num_res].flags = IORESOURCE_IRQ; + + num_res++; + } + + return num_res; +} + +/** + * apmt_add_platform_device() - Allocate a platform device for APMT node + * @node: Pointer to device ACPI APMT node + * @fwnode: fwnode associated with the APMT node + * + * Returns: 0 on success, <0 failure + */ +static int __init apmt_add_platform_device(struct acpi_apmt_node *node, + struct fwnode_handle *fwnode) +{ + struct platform_device *pdev; + int ret, count; + struct resource res[DEV_MAX_RESOURCE_COUNT]; + + pdev = platform_device_alloc(DEV_NAME, PLATFORM_DEVID_AUTO); + if (!pdev) + return -ENOMEM; + + memset(res, 0, sizeof(res)); + + count = apmt_init_resources(res, node); + + ret = platform_device_add_resources(pdev, res, count); + if (ret) + goto dev_put; + + /* + * Add a copy of APMT node pointer to platform_data to be used to + * retrieve APMT data information. + */ + ret = platform_device_add_data(pdev, &node, sizeof(node)); + if (ret) + goto dev_put; + + pdev->dev.fwnode = fwnode; + + ret = platform_device_add(pdev); + + if (ret) + goto dev_put; + + return 0; + +dev_put: + platform_device_put(pdev); + + return ret; +} + +static int __init apmt_init_platform_devices(void) +{ + struct acpi_apmt_node *apmt_node; + struct acpi_table_apmt *apmt; + struct fwnode_handle *fwnode; + u64 offset, end; + int ret; + + /* + * apmt_table and apmt both point to the start of APMT table, but + * have different struct types + */ + apmt = (struct acpi_table_apmt *)apmt_table; + offset = sizeof(*apmt); + end = apmt->header.length; + + while (offset < end) { + apmt_node = ACPI_ADD_PTR(struct acpi_apmt_node, apmt, + offset); + + fwnode = acpi_alloc_fwnode_static(); + if (!fwnode) + return -ENOMEM; + + ret = apmt_add_platform_device(apmt_node, fwnode); + if (ret) { + acpi_free_fwnode_static(fwnode); + return ret; + } + + offset += apmt_node->length; + } + + return 0; +} + +void __init acpi_apmt_init(void) +{ + acpi_status status; + int ret; + + /** + * APMT table nodes will be used at runtime after the apmt init, + * so we don't need to call acpi_put_table() to release + * the APMT table mapping. + */ + status = acpi_get_table(ACPI_SIG_APMT, 0, &apmt_table); + + if (ACPI_FAILURE(status)) { + if (status != AE_NOT_FOUND) { + const char *msg = acpi_format_exception(status); + + pr_err("Failed to get APMT table, %s\n", msg); + } + + return; + } + + ret = apmt_init_platform_devices(); + if (ret) { + pr_err("Failed to initialize APMT platform devices, ret: %d\n", ret); + acpi_put_table(apmt_table); + } +} |