diff options
Diffstat (limited to 'drivers/acpi')
| -rw-r--r-- | drivers/acpi/Kconfig | 17 | ||||
| -rw-r--r-- | drivers/acpi/Makefile | 1 | ||||
| -rw-r--r-- | drivers/acpi/acpi_pcc.c | 120 | ||||
| -rw-r--r-- | drivers/acpi/bus.c | 1 |
4 files changed, 139 insertions, 0 deletions
diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig index cdbdf68bd98f..60b5424bd318 100644 --- a/drivers/acpi/Kconfig +++ b/drivers/acpi/Kconfig @@ -524,6 +524,23 @@ config ACPI_PPTT bool endif +config ACPI_PCC + bool "ACPI PCC Address Space" + depends on PCC + default y + help + The PCC Address Space also referred as PCC Operation Region pertains + to the region of PCC subspace that succeeds the PCC signature. + + The PCC Operation Region works in conjunction with the PCC Table + (Platform Communications Channel Table). PCC subspaces that are + marked for use as PCC Operation Regions must not be used as PCC + subspaces for the standard ACPI features such as CPPC, RASF, PDTT and + MPST. These standard features must always use the PCC Table instead. + + Enable this feature if you want to set up and install the PCC Address + Space handler to handle PCC OpRegion in the firmware. + source "drivers/acpi/pmic/Kconfig" config ACPI_VIOT diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile index 3018714e87d9..08c2d985c57c 100644 --- a/drivers/acpi/Makefile +++ b/drivers/acpi/Makefile @@ -67,6 +67,7 @@ acpi-$(CONFIG_ACPI_LPIT) += acpi_lpit.o acpi-$(CONFIG_ACPI_GENERIC_GSI) += irq.o acpi-$(CONFIG_ACPI_WATCHDOG) += acpi_watchdog.o acpi-$(CONFIG_ACPI_PRMT) += prmt.o +acpi-$(CONFIG_ACPI_PCC) += acpi_pcc.o # Address translation acpi-$(CONFIG_ACPI_ADXL) += acpi_adxl.o diff --git a/drivers/acpi/acpi_pcc.c b/drivers/acpi/acpi_pcc.c new file mode 100644 index 000000000000..41e3ebd204ff --- /dev/null +++ b/drivers/acpi/acpi_pcc.c @@ -0,0 +1,120 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Author: Sudeep Holla <sudeep.holla@arm.com> + * Copyright 2021 Arm Limited + * + * The PCC Address Space also referred as PCC Operation Region pertains to the + * region of PCC subspace that succeeds the PCC signature. The PCC Operation + * Region works in conjunction with the PCC Table(Platform Communications + * Channel Table). PCC subspaces that are marked for use as PCC Operation + * Regions must not be used as PCC subspaces for the standard ACPI features + * such as CPPC, RASF, PDTT and MPST. These standard features must always use + * the PCC Table instead. + * + * This driver sets up the PCC Address Space and installs an handler to enable + * handling of PCC OpRegion in the firmware. + * + */ +#include <linux/kernel.h> +#include <linux/acpi.h> +#include <linux/completion.h> +#include <linux/idr.h> +#include <linux/io.h> + +#include <acpi/pcc.h> + +struct pcc_data { + struct pcc_mbox_chan *pcc_chan; + void __iomem *pcc_comm_addr; + struct completion done; + struct mbox_client cl; + struct acpi_pcc_info ctx; +}; + +struct acpi_pcc_info pcc_ctx; + +static void pcc_rx_callback(struct mbox_client *cl, void *m) +{ + struct pcc_data *data = container_of(cl, struct pcc_data, cl); + + complete(&data->done); +} + +static acpi_status +acpi_pcc_address_space_setup(acpi_handle region_handle, u32 function, + void *handler_context, void **region_context) +{ + struct pcc_data *data; + struct acpi_pcc_info *ctx = handler_context; + struct pcc_mbox_chan *pcc_chan; + + data = kzalloc(sizeof(*data), GFP_KERNEL); + if (!data) + return AE_NO_MEMORY; + + data->cl.rx_callback = pcc_rx_callback; + data->cl.knows_txdone = true; + data->ctx.length = ctx->length; + data->ctx.subspace_id = ctx->subspace_id; + data->ctx.internal_buffer = ctx->internal_buffer; + + init_completion(&data->done); + data->pcc_chan = pcc_mbox_request_channel(&data->cl, ctx->subspace_id); + if (IS_ERR(data->pcc_chan)) { + pr_err("Failed to find PCC channel for subspace %d\n", + ctx->subspace_id); + return AE_NOT_FOUND; + } + + pcc_chan = data->pcc_chan; + data->pcc_comm_addr = acpi_os_ioremap(pcc_chan->shmem_base_addr, + pcc_chan->shmem_size); + if (!data->pcc_comm_addr) { + pr_err("Failed to ioremap PCC comm region mem for %d\n", + ctx->subspace_id); + return AE_NO_MEMORY; + } + + *region_context = data; + return AE_OK; +} + +static acpi_status +acpi_pcc_address_space_handler(u32 function, acpi_physical_address addr, + u32 bits, acpi_integer *value, + void *handler_context, void *region_context) +{ + int ret; + struct pcc_data *data = region_context; + + reinit_completion(&data->done); + + /* Write to Shared Memory */ + memcpy_toio(data->pcc_comm_addr, (void *)value, data->ctx.length); + + ret = mbox_send_message(data->pcc_chan->mchan, NULL); + if (ret < 0) + return AE_ERROR; + + if (data->pcc_chan->mchan->mbox->txdone_irq) + wait_for_completion(&data->done); + + mbox_client_txdone(data->pcc_chan->mchan, ret); + + memcpy_fromio(value, data->pcc_comm_addr, data->ctx.length); + + return AE_OK; +} + +void __init acpi_init_pcc(void) +{ + acpi_status status; + + status = acpi_install_address_space_handler(ACPI_ROOT_OBJECT, + ACPI_ADR_SPACE_PLATFORM_COMM, + &acpi_pcc_address_space_handler, + &acpi_pcc_address_space_setup, + &pcc_ctx); + if (ACPI_FAILURE(status)) + pr_alert("OperationRegion handler could not be installed\n"); +} diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c index fa923a929224..b64014b4203e 100644 --- a/drivers/acpi/bus.c +++ b/drivers/acpi/bus.c @@ -1320,6 +1320,7 @@ static int __init acpi_init(void) pr_debug("%s: kset create error\n", __func__); init_prmt(); + acpi_init_pcc(); result = acpi_bus_init(); if (result) { kobject_put(acpi_kobj); |