summaryrefslogtreecommitdiff
path: root/drivers/dma/ptdma/ptdma-dev.c
blob: 8a6bf291a73fe7306b01e272d5344a12cb88f733 (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
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
// SPDX-License-Identifier: GPL-2.0-only
/*
 * AMD Passthru DMA device driver
 * -- Based on the CCP driver
 *
 * Copyright (C) 2016,2021 Advanced Micro Devices, Inc.
 *
 * Author: Sanjay R Mehta <sanju.mehta@amd.com>
 * Author: Gary R Hook <gary.hook@amd.com>
 */

#include <linux/bitfield.h>
#include <linux/dma-mapping.h>
#include <linux/debugfs.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pci.h>

#include "ptdma.h"

/* Human-readable error strings */
static char *pt_error_codes[] = {
	"",
	"ERR 01: ILLEGAL_ENGINE",
	"ERR 03: ILLEGAL_FUNCTION_TYPE",
	"ERR 04: ILLEGAL_FUNCTION_MODE",
	"ERR 06: ILLEGAL_FUNCTION_SIZE",
	"ERR 08: ILLEGAL_FUNCTION_RSVD",
	"ERR 09: ILLEGAL_BUFFER_LENGTH",
	"ERR 10: VLSB_FAULT",
	"ERR 11: ILLEGAL_MEM_ADDR",
	"ERR 12: ILLEGAL_MEM_SEL",
	"ERR 13: ILLEGAL_CONTEXT_ID",
	"ERR 15: 0xF Reserved",
	"ERR 18: CMD_TIMEOUT",
	"ERR 19: IDMA0_AXI_SLVERR",
	"ERR 20: IDMA0_AXI_DECERR",
	"ERR 21: 0x15 Reserved",
	"ERR 22: IDMA1_AXI_SLAVE_FAULT",
	"ERR 23: IDMA1_AIXI_DECERR",
	"ERR 24: 0x18 Reserved",
	"ERR 27: 0x1B Reserved",
	"ERR 38: ODMA0_AXI_SLVERR",
	"ERR 39: ODMA0_AXI_DECERR",
	"ERR 40: 0x28 Reserved",
	"ERR 41: ODMA1_AXI_SLVERR",
	"ERR 42: ODMA1_AXI_DECERR",
	"ERR 43: LSB_PARITY_ERR",
};

static void pt_log_error(struct pt_device *d, int e)
{
	dev_err(d->dev, "PTDMA error: %s (0x%x)\n", pt_error_codes[e], e);
}

void pt_start_queue(struct pt_cmd_queue *cmd_q)
{
	/* Turn on the run bit */
	iowrite32(cmd_q->qcontrol | CMD_Q_RUN, cmd_q->reg_control);
}

void pt_stop_queue(struct pt_cmd_queue *cmd_q)
{
	/* Turn off the run bit */
	iowrite32(cmd_q->qcontrol & ~CMD_Q_RUN, cmd_q->reg_control);
}

static int pt_core_execute_cmd(struct ptdma_desc *desc, struct pt_cmd_queue *cmd_q)
{
	bool soc = FIELD_GET(DWORD0_SOC, desc->dw0);
	u8 *q_desc = (u8 *)&cmd_q->qbase[cmd_q->qidx];
	u32 tail;

	if (soc) {
		desc->dw0 |= FIELD_PREP(DWORD0_IOC, desc->dw0);
		desc->dw0 &= ~DWORD0_SOC;
	}
	mutex_lock(&cmd_q->q_mutex);

	/* Copy 32-byte command descriptor to hw queue. */
	memcpy(q_desc, desc, 32);
	cmd_q->qidx = (cmd_q->qidx + 1) % CMD_Q_LEN;

	/* The data used by this command must be flushed to memory */
	wmb();

	/* Write the new tail address back to the queue register */
	tail = lower_32_bits(cmd_q->qdma_tail + cmd_q->qidx * Q_DESC_SIZE);
	iowrite32(tail, cmd_q->reg_control + 0x0004);

	/* Turn the queue back on using our cached control register */
	pt_start_queue(cmd_q);
	mutex_unlock(&cmd_q->q_mutex);

	return 0;
}

int pt_core_perform_passthru(struct pt_cmd_queue *cmd_q,
			     struct pt_passthru_engine *pt_engine)
{
	struct ptdma_desc desc;

	cmd_q->cmd_error = 0;
	cmd_q->total_pt_ops++;
	memset(&desc, 0, sizeof(desc));
	desc.dw0 = CMD_DESC_DW0_VAL;
	desc.length = pt_engine->src_len;
	desc.src_lo = lower_32_bits(pt_engine->src_dma);
	desc.dw3.src_hi = upper_32_bits(pt_engine->src_dma);
	desc.dst_lo = lower_32_bits(pt_engine->dst_dma);
	desc.dw5.dst_hi = upper_32_bits(pt_engine->dst_dma);

	return pt_core_execute_cmd(&desc, cmd_q);
}

static inline void pt_core_disable_queue_interrupts(struct pt_device *pt)
{
	iowrite32(0, pt->cmd_q.reg_control + 0x000C);
}

static inline void pt_core_enable_queue_interrupts(struct pt_device *pt)
{
	iowrite32(SUPPORTED_INTERRUPTS, pt->cmd_q.reg_control + 0x000C);
}

static void pt_do_cmd_complete(unsigned long data)
{
	struct pt_tasklet_data *tdata = (struct pt_tasklet_data *)data;
	struct pt_cmd *cmd = tdata->cmd;
	struct pt_cmd_queue *cmd_q = &cmd->pt->cmd_q;
	u32 tail;

	if (cmd_q->cmd_error) {
	       /*
		* Log the error and flush the queue by
		* moving the head pointer
		*/
		tail = lower_32_bits(cmd_q->qdma_tail + cmd_q->qidx * Q_DESC_SIZE);
		pt_log_error(cmd_q->pt, cmd_q->cmd_error);
		iowrite32(tail, cmd_q->reg_control + 0x0008);
	}

	cmd->pt_cmd_callback(cmd->data, cmd->ret);
}

static irqreturn_t pt_core_irq_handler(int irq, void *data)
{
	struct pt_device *pt = data;
	struct pt_cmd_queue *cmd_q = &pt->cmd_q;
	u32 status;

	pt_core_disable_queue_interrupts(pt);
	pt->total_interrupts++;
	status = ioread32(cmd_q->reg_control + 0x0010);
	if (status) {
		cmd_q->int_status = status;
		cmd_q->q_status = ioread32(cmd_q->reg_control + 0x0100);
		cmd_q->q_int_status = ioread32(cmd_q->reg_control + 0x0104);

		/* On error, only save the first error value */
		if ((status & INT_ERROR) && !cmd_q->cmd_error)
			cmd_q->cmd_error = CMD_Q_ERROR(cmd_q->q_status);

		/* Acknowledge the interrupt */
		iowrite32(status, cmd_q->reg_control + 0x0010);
		pt_core_enable_queue_interrupts(pt);
		pt_do_cmd_complete((ulong)&pt->tdata);
	}
	return IRQ_HANDLED;
}

int pt_core_init(struct pt_device *pt)
{
	char dma_pool_name[MAX_DMAPOOL_NAME_LEN];
	struct pt_cmd_queue *cmd_q = &pt->cmd_q;
	u32 dma_addr_lo, dma_addr_hi;
	struct device *dev = pt->dev;
	struct dma_pool *dma_pool;
	int ret;

	/* Allocate a dma pool for the queue */
	snprintf(dma_pool_name, sizeof(dma_pool_name), "%s_q", dev_name(pt->dev));

	dma_pool = dma_pool_create(dma_pool_name, dev,
				   PT_DMAPOOL_MAX_SIZE,
				   PT_DMAPOOL_ALIGN, 0);
	if (!dma_pool)
		return -ENOMEM;

	/* ptdma core initialisation */
	iowrite32(CMD_CONFIG_VHB_EN, pt->io_regs + CMD_CONFIG_OFFSET);
	iowrite32(CMD_QUEUE_PRIO, pt->io_regs + CMD_QUEUE_PRIO_OFFSET);
	iowrite32(CMD_TIMEOUT_DISABLE, pt->io_regs + CMD_TIMEOUT_OFFSET);
	iowrite32(CMD_CLK_GATE_CONFIG, pt->io_regs + CMD_CLK_GATE_CTL_OFFSET);
	iowrite32(CMD_CONFIG_REQID, pt->io_regs + CMD_REQID_CONFIG_OFFSET);

	cmd_q->pt = pt;
	cmd_q->dma_pool = dma_pool;
	mutex_init(&cmd_q->q_mutex);

	/* Page alignment satisfies our needs for N <= 128 */
	cmd_q->qsize = Q_SIZE(Q_DESC_SIZE);
	cmd_q->qbase = dma_alloc_coherent(dev, cmd_q->qsize,
					  &cmd_q->qbase_dma,
					  GFP_KERNEL);
	if (!cmd_q->qbase) {
		dev_err(dev, "unable to allocate command queue\n");
		ret = -ENOMEM;
		goto e_dma_alloc;
	}

	cmd_q->qidx = 0;

	/* Preset some register values */
	cmd_q->reg_control = pt->io_regs + CMD_Q_STATUS_INCR;

	/* Turn off the queues and disable interrupts until ready */
	pt_core_disable_queue_interrupts(pt);

	cmd_q->qcontrol = 0; /* Start with nothing */
	iowrite32(cmd_q->qcontrol, cmd_q->reg_control);

	ioread32(cmd_q->reg_control + 0x0104);
	ioread32(cmd_q->reg_control + 0x0100);

	/* Clear the interrupt status */
	iowrite32(SUPPORTED_INTERRUPTS, cmd_q->reg_control + 0x0010);

	/* Request an irq */
	ret = request_irq(pt->pt_irq, pt_core_irq_handler, 0, dev_name(pt->dev), pt);
	if (ret)
		goto e_pool;

	/* Update the device registers with queue information. */
	cmd_q->qcontrol &= ~CMD_Q_SIZE;
	cmd_q->qcontrol |= FIELD_PREP(CMD_Q_SIZE, QUEUE_SIZE_VAL);

	cmd_q->qdma_tail = cmd_q->qbase_dma;
	dma_addr_lo = lower_32_bits(cmd_q->qdma_tail);
	iowrite32((u32)dma_addr_lo, cmd_q->reg_control + 0x0004);
	iowrite32((u32)dma_addr_lo, cmd_q->reg_control + 0x0008);

	dma_addr_hi = upper_32_bits(cmd_q->qdma_tail);
	cmd_q->qcontrol |= (dma_addr_hi << 16);
	iowrite32(cmd_q->qcontrol, cmd_q->reg_control);

	pt_core_enable_queue_interrupts(pt);

	/* Register the DMA engine support */
	ret = pt_dmaengine_register(pt);
	if (ret)
		goto e_dmaengine;

	/* Set up debugfs entries */
	ptdma_debugfs_setup(pt);

	return 0;

e_dmaengine:
	free_irq(pt->pt_irq, pt);

e_dma_alloc:
	dma_free_coherent(dev, cmd_q->qsize, cmd_q->qbase, cmd_q->qbase_dma);

e_pool:
	dev_err(dev, "unable to allocate an IRQ\n");
	dma_pool_destroy(pt->cmd_q.dma_pool);

	return ret;
}

void pt_core_destroy(struct pt_device *pt)
{
	struct device *dev = pt->dev;
	struct pt_cmd_queue *cmd_q = &pt->cmd_q;
	struct pt_cmd *cmd;

	/* Unregister the DMA engine */
	pt_dmaengine_unregister(pt);

	/* Disable and clear interrupts */
	pt_core_disable_queue_interrupts(pt);

	/* Turn off the run bit */
	pt_stop_queue(cmd_q);

	/* Clear the interrupt status */
	iowrite32(SUPPORTED_INTERRUPTS, cmd_q->reg_control + 0x0010);
	ioread32(cmd_q->reg_control + 0x0104);
	ioread32(cmd_q->reg_control + 0x0100);

	free_irq(pt->pt_irq, pt);

	dma_free_coherent(dev, cmd_q->qsize, cmd_q->qbase,
			  cmd_q->qbase_dma);

	/* Flush the cmd queue */
	while (!list_empty(&pt->cmd)) {
		/* Invoke the callback directly with an error code */
		cmd = list_first_entry(&pt->cmd, struct pt_cmd, entry);
		list_del(&cmd->entry);
		cmd->pt_cmd_callback(cmd->data, -ENODEV);
	}
}