summaryrefslogtreecommitdiff
path: root/drivers/net/ipa/ipa_uc.c
blob: b382d47bc70d9307dccbc920ce31175490316e73 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
// 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 */

/* 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		= 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_setup() 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);
}