diff options
Diffstat (limited to 'drivers/net/ipa/ipa_uc.c')
| -rw-r--r-- | drivers/net/ipa/ipa_uc.c | 211 |
1 files changed, 211 insertions, 0 deletions
diff --git a/drivers/net/ipa/ipa_uc.c b/drivers/net/ipa/ipa_uc.c new file mode 100644 index 000000000000..a1f8db00d55a --- /dev/null +++ b/drivers/net/ipa/ipa_uc.c @@ -0,0 +1,211 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* Copyright (c) 2012-2018, The Linux Foundation. All rights reserved. + * Copyright (C) 2018-2020 Linaro Ltd. + */ + +#include <linux/types.h> +#include <linux/io.h> +#include <linux/delay.h> + +#include "ipa.h" +#include "ipa_clock.h" +#include "ipa_uc.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 */ + +/* Offset relative to the base of the IPA shared address space of the + * shared region used for communication with the microcontroller. The + * region is 128 bytes in size, but only the first 40 bytes are used. + */ +#define IPA_MEM_UC_OFFSET 0x0000 + +/* 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) + * @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) + * @response_param: response parameter (microcontroller->AP) + * + * @event: event code (microcontroller->AP) + * @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 + * @interface_version: hardware-reported interface version + */ +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 = 0, + IPA_UC_COMMAND_UPDATE_FLAGS = 1, + IPA_UC_COMMAND_DEBUG_RUN_TEST = 2, + IPA_UC_COMMAND_DEBUG_GET_INFO = 3, + IPA_UC_COMMAND_ERR_FATAL = 4, + IPA_UC_COMMAND_CLK_GATE = 5, + IPA_UC_COMMAND_CLK_UNGATE = 6, + IPA_UC_COMMAND_MEMCPY = 7, + IPA_UC_COMMAND_RESET_PIPE = 8, + IPA_UC_COMMAND_REG_WRITE = 9, + IPA_UC_COMMAND_GSI_CH_EMPTY = 10, +}; + +/** enum ipa_uc_response - microcontroller response codes */ +enum ipa_uc_response { + IPA_UC_RESPONSE_NO_OP = 0, + IPA_UC_RESPONSE_INIT_COMPLETED = 1, + IPA_UC_RESPONSE_CMD_COMPLETED = 2, + IPA_UC_RESPONSE_DEBUG_GET_INFO = 3, +}; + +/** enum ipa_uc_event - common cpu events reported by the microcontroller */ +enum ipa_uc_event { + IPA_UC_EVENT_NO_OP = 0, + IPA_UC_EVENT_ERROR = 1, + IPA_UC_EVENT_LOG_INFO = 2, +}; + +static struct ipa_uc_mem_area *ipa_uc_shared(struct ipa *ipa) +{ + u32 offset = ipa->mem_offset + ipa->mem[IPA_MEM_UC_SHARED].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 + dev_err(dev, "unsupported microcontroller event %hhu\n", + shared->event); +} + +/* 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); + + /* 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 clock reference taken in ipa_uc_init() once we + * know the microcontroller has finished its initialization. + */ + switch (shared->response) { + case IPA_UC_RESPONSE_INIT_COMPLETED: + ipa->uc_loaded = true; + ipa_clock_put(ipa); + break; + default: + dev_warn(&ipa->pdev->dev, + "unsupported microcontroller response %hhu\n", + shared->response); + break; + } +} + +/* ipa_uc_setup() - Set up the microcontroller */ +void ipa_uc_setup(struct ipa *ipa) +{ + /* The microcontroller needs the IPA clock running until it has + * completed its initialization. It signals this by sending an + * INIT_COMPLETED response message to the AP. This could occur after + * we have finished doing the rest of the IPA initialization, so we + * need to take an extra "proxy" reference, and hold it until we've + * received that signal. (This reference is dropped in + * ipa_uc_response_hdlr(), above.) + */ + ipa_clock_get(ipa); + + 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_setup() */ +void ipa_uc_teardown(struct ipa *ipa) +{ + ipa_interrupt_remove(ipa->interrupt, IPA_IRQ_UC_1); + ipa_interrupt_remove(ipa->interrupt, IPA_IRQ_UC_0); + if (!ipa->uc_loaded) + ipa_clock_put(ipa); +} + +/* 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); + + shared->command = command; + shared->command_param = cpu_to_le32(command_param); + shared->command_param_hi = 0; + shared->response = 0; + shared->response_param = 0; + + iowrite32(1, ipa->reg_virt + IPA_REG_IRQ_UC_OFFSET); +} + +/* 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); +} |