diff options
Diffstat (limited to 'drivers/net/ipa/ipa_uc.c')
| -rw-r--r-- | drivers/net/ipa/ipa_uc.c | 252 |
1 files changed, 252 insertions, 0 deletions
diff --git a/drivers/net/ipa/ipa_uc.c b/drivers/net/ipa/ipa_uc.c new file mode 100644 index 000000000..f0ee47281 --- /dev/null +++ b/drivers/net/ipa/ipa_uc.c @@ -0,0 +1,252 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* Copyright (c) 2012-2018, The Linux Foundation. All rights reserved. + * Copyright (C) 2018-2022 Linaro Ltd. + */ + +#include <linux/types.h> +#include <linux/io.h> +#include <linux/delay.h> +#include <linux/pm_runtime.h> + +#include "ipa.h" +#include "ipa_uc.h" +#include "ipa_power.h" + +/** + * DOC: The IPA embedded microcontroller + * + * The IPA incorporates a microcontroller that is able to do some additional + * handling/offloading of network activity. The current code makes + * essentially no use of the microcontroller, but it still requires some + * initialization. It needs to be notified in the event the AP crashes. + * + * The microcontroller can generate two interrupts to the AP. One interrupt + * is used to indicate that a response to a request from the AP is available. + * The other is used to notify the AP of the occurrence of an event. In + * addition, the AP can interrupt the microcontroller by writing a register. + * + * A 128 byte block of structured memory within the IPA SRAM is used together + * with these interrupts to implement the communication interface between the + * AP and the IPA microcontroller. Each side writes data to the shared area + * before interrupting its peer, which will read the written data in response + * to the interrupt. Some information found in the shared area is currently + * unused. All remaining space in the shared area is reserved, and must not + * be read or written by the AP. + */ +/* Supports hardware interface version 0x2000 */ + +/* Delay to allow a the microcontroller to save state when crashing */ +#define IPA_SEND_DELAY 100 /* microseconds */ + +/** + * struct ipa_uc_mem_area - AP/microcontroller shared memory area + * @command: command code (AP->microcontroller) + * @reserved0: reserved bytes; avoid reading or writing + * @command_param: low 32 bits of command parameter (AP->microcontroller) + * @command_param_hi: high 32 bits of command parameter (AP->microcontroller) + * + * @response: response code (microcontroller->AP) + * @reserved1: reserved bytes; avoid reading or writing + * @response_param: response parameter (microcontroller->AP) + * + * @event: event code (microcontroller->AP) + * @reserved2: reserved bytes; avoid reading or writing + * @event_param: event parameter (microcontroller->AP) + * + * @first_error_address: address of first error-source on SNOC + * @hw_state: state of hardware (including error type information) + * @warning_counter: counter of non-fatal hardware errors + * @reserved3: reserved bytes; avoid reading or writing + * @interface_version: hardware-reported interface version + * @reserved4: reserved bytes; avoid reading or writing + * + * A shared memory area at the base of IPA resident memory is used for + * communication with the microcontroller. The region is 128 bytes in + * size, but only the first 40 bytes (structured this way) are used. + */ +struct ipa_uc_mem_area { + u8 command; /* enum ipa_uc_command */ + u8 reserved0[3]; + __le32 command_param; + __le32 command_param_hi; + u8 response; /* enum ipa_uc_response */ + u8 reserved1[3]; + __le32 response_param; + u8 event; /* enum ipa_uc_event */ + u8 reserved2[3]; + + __le32 event_param; + __le32 first_error_address; + u8 hw_state; + u8 warning_counter; + __le16 reserved3; + __le16 interface_version; + __le16 reserved4; +}; + +/** enum ipa_uc_command - commands from the AP to the microcontroller */ +enum ipa_uc_command { + IPA_UC_COMMAND_NO_OP = 0x0, + IPA_UC_COMMAND_UPDATE_FLAGS = 0x1, + IPA_UC_COMMAND_DEBUG_RUN_TEST = 0x2, + IPA_UC_COMMAND_DEBUG_GET_INFO = 0x3, + IPA_UC_COMMAND_ERR_FATAL = 0x4, + IPA_UC_COMMAND_CLK_GATE = 0x5, + IPA_UC_COMMAND_CLK_UNGATE = 0x6, + IPA_UC_COMMAND_MEMCPY = 0x7, + IPA_UC_COMMAND_RESET_PIPE = 0x8, + IPA_UC_COMMAND_REG_WRITE = 0x9, + IPA_UC_COMMAND_GSI_CH_EMPTY = 0xa, +}; + +/** enum ipa_uc_response - microcontroller response codes */ +enum ipa_uc_response { + IPA_UC_RESPONSE_NO_OP = 0x0, + IPA_UC_RESPONSE_INIT_COMPLETED = 0x1, + IPA_UC_RESPONSE_CMD_COMPLETED = 0x2, + IPA_UC_RESPONSE_DEBUG_GET_INFO = 0x3, +}; + +/** enum ipa_uc_event - common cpu events reported by the microcontroller */ +enum ipa_uc_event { + IPA_UC_EVENT_NO_OP = 0x0, + IPA_UC_EVENT_ERROR = 0x1, + IPA_UC_EVENT_LOG_INFO = 0x2, +}; + +static struct ipa_uc_mem_area *ipa_uc_shared(struct ipa *ipa) +{ + const struct ipa_mem *mem = ipa_mem_find(ipa, IPA_MEM_UC_SHARED); + u32 offset = ipa->mem_offset + mem->offset; + + return ipa->mem_virt + offset; +} + +/* Microcontroller event IPA interrupt handler */ +static void ipa_uc_event_handler(struct ipa *ipa, enum ipa_irq_id irq_id) +{ + struct ipa_uc_mem_area *shared = ipa_uc_shared(ipa); + struct device *dev = &ipa->pdev->dev; + + if (shared->event == IPA_UC_EVENT_ERROR) + dev_err(dev, "microcontroller error event\n"); + else if (shared->event != IPA_UC_EVENT_LOG_INFO) + dev_err(dev, "unsupported microcontroller event %u\n", + shared->event); + /* The LOG_INFO event can be safely ignored */ +} + +/* Microcontroller response IPA interrupt handler */ +static void ipa_uc_response_hdlr(struct ipa *ipa, enum ipa_irq_id irq_id) +{ + struct ipa_uc_mem_area *shared = ipa_uc_shared(ipa); + struct device *dev = &ipa->pdev->dev; + + /* An INIT_COMPLETED response message is sent to the AP by the + * microcontroller when it is operational. Other than this, the AP + * should only receive responses from the microcontroller when it has + * sent it a request message. + * + * We can drop the power reference taken in ipa_uc_power() once we + * know the microcontroller has finished its initialization. + */ + switch (shared->response) { + case IPA_UC_RESPONSE_INIT_COMPLETED: + if (ipa->uc_powered) { + ipa->uc_loaded = true; + ipa_power_retention(ipa, true); + pm_runtime_mark_last_busy(dev); + (void)pm_runtime_put_autosuspend(dev); + ipa->uc_powered = false; + } else { + dev_warn(dev, "unexpected init_completed response\n"); + } + break; + default: + dev_warn(dev, "unsupported microcontroller response %u\n", + shared->response); + break; + } +} + +/* Configure the IPA microcontroller subsystem */ +void ipa_uc_config(struct ipa *ipa) +{ + ipa->uc_powered = false; + ipa->uc_loaded = false; + ipa_interrupt_add(ipa->interrupt, IPA_IRQ_UC_0, ipa_uc_event_handler); + ipa_interrupt_add(ipa->interrupt, IPA_IRQ_UC_1, ipa_uc_response_hdlr); +} + +/* Inverse of ipa_uc_config() */ +void ipa_uc_deconfig(struct ipa *ipa) +{ + struct device *dev = &ipa->pdev->dev; + + ipa_interrupt_remove(ipa->interrupt, IPA_IRQ_UC_1); + ipa_interrupt_remove(ipa->interrupt, IPA_IRQ_UC_0); + if (ipa->uc_loaded) + ipa_power_retention(ipa, false); + + if (!ipa->uc_powered) + return; + + pm_runtime_mark_last_busy(dev); + (void)pm_runtime_put_autosuspend(dev); +} + +/* Take a proxy power reference for the microcontroller */ +void ipa_uc_power(struct ipa *ipa) +{ + static bool already; + struct device *dev; + int ret; + + if (already) + return; + already = true; /* Only do this on first boot */ + + /* This power reference dropped in ipa_uc_response_hdlr() above */ + dev = &ipa->pdev->dev; + ret = pm_runtime_get_sync(dev); + if (ret < 0) { + pm_runtime_put_noidle(dev); + dev_err(dev, "error %d getting proxy power\n", ret); + } else { + ipa->uc_powered = true; + } +} + +/* Send a command to the microcontroller */ +static void send_uc_command(struct ipa *ipa, u32 command, u32 command_param) +{ + struct ipa_uc_mem_area *shared = ipa_uc_shared(ipa); + const struct ipa_reg *reg; + u32 val; + + /* Fill in the command data */ + shared->command = command; + shared->command_param = cpu_to_le32(command_param); + shared->command_param_hi = 0; + shared->response = 0; + shared->response_param = 0; + + /* Use an interrupt to tell the microcontroller the command is ready */ + reg = ipa_reg(ipa, IPA_IRQ_UC); + val = ipa_reg_bit(reg, UC_INTR); + + iowrite32(val, ipa->reg_virt + ipa_reg_offset(reg)); +} + +/* Tell the microcontroller the AP is shutting down */ +void ipa_uc_panic_notifier(struct ipa *ipa) +{ + if (!ipa->uc_loaded) + return; + + send_uc_command(ipa, IPA_UC_COMMAND_ERR_FATAL, 0); + + /* give uc enough time to save state */ + udelay(IPA_SEND_DELAY); +} |