2 * Copyright (c) 2013-2014, The Linux Foundation. All rights reserved.
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 and
6 * only version 2 as published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
15 * QCOM BAM DMA engine driver
17 * QCOM BAM DMA blocks are distributed amongst a number of the on-chip
18 * peripherals on the MSM 8x74. The configuration of the channels are dependent
19 * on the way they are hard wired to that specific peripheral. The peripheral
20 * device tree entries specify the configuration of each channel.
22 * The DMA controller requires the use of external memory for storage of the
23 * hardware descriptors for each channel. The descriptor FIFO is accessed as a
24 * circular buffer and operations are managed according to the offset within the
25 * FIFO. After pipe/channel reset, all of the pipe registers and internal state
26 * are back to defaults.
28 * During DMA operations, we write descriptors to the FIFO, being careful to
29 * handle wrapping and then write the last FIFO offset to that channel's
30 * P_EVNT_REG register to kick off the transaction. The P_SW_OFSTS register
31 * indicates the current FIFO offset that is being processed, so there is some
32 * indication of where the hardware is currently working.
35 #include <linux/kernel.h>
37 #include <linux/init.h>
38 #include <linux/slab.h>
39 #include <linux/module.h>
40 #include <linux/interrupt.h>
41 #include <linux/dma-mapping.h>
42 #include <linux/scatterlist.h>
43 #include <linux/device.h>
44 #include <linux/platform_device.h>
46 #include <linux/of_address.h>
47 #include <linux/of_irq.h>
48 #include <linux/of_dma.h>
49 #include <linux/clk.h>
50 #include <linux/dmaengine.h>
51 #include <linux/pm_runtime.h>
53 #include "../dmaengine.h"
54 #include "../virt-dma.h"
57 __le32 addr; /* Buffer physical address */
58 __le16 size; /* Buffer size in bytes */
62 #define BAM_DMA_AUTOSUSPEND_DELAY 100
64 #define DESC_FLAG_INT BIT(15)
65 #define DESC_FLAG_EOT BIT(14)
66 #define DESC_FLAG_EOB BIT(13)
67 #define DESC_FLAG_NWD BIT(12)
68 #define DESC_FLAG_CMD BIT(11)
70 struct bam_async_desc {
71 struct virt_dma_desc vd;
76 /* transaction flags, EOT|EOB|NWD */
79 struct bam_desc_hw *curr_desc;
81 enum dma_transfer_direction dir;
83 struct bam_desc_hw desc[0];
93 BAM_IRQ_SRCS_UNMASKED,
106 BAM_P_EVNT_DEST_ADDR,
109 BAM_P_DATA_FIFO_ADDR,
110 BAM_P_DESC_FIFO_ADDR,
111 BAM_P_EVNT_GEN_TRSHLD,
115 struct reg_offset_data {
117 unsigned int pipe_mult, evnt_mult, ee_mult;
120 static const struct reg_offset_data bam_v1_3_reg_info[] = {
121 [BAM_CTRL] = { 0x0F80, 0x00, 0x00, 0x00 },
122 [BAM_REVISION] = { 0x0F84, 0x00, 0x00, 0x00 },
123 [BAM_NUM_PIPES] = { 0x0FBC, 0x00, 0x00, 0x00 },
124 [BAM_DESC_CNT_TRSHLD] = { 0x0F88, 0x00, 0x00, 0x00 },
125 [BAM_IRQ_SRCS] = { 0x0F8C, 0x00, 0x00, 0x00 },
126 [BAM_IRQ_SRCS_MSK] = { 0x0F90, 0x00, 0x00, 0x00 },
127 [BAM_IRQ_SRCS_UNMASKED] = { 0x0FB0, 0x00, 0x00, 0x00 },
128 [BAM_IRQ_STTS] = { 0x0F94, 0x00, 0x00, 0x00 },
129 [BAM_IRQ_CLR] = { 0x0F98, 0x00, 0x00, 0x00 },
130 [BAM_IRQ_EN] = { 0x0F9C, 0x00, 0x00, 0x00 },
131 [BAM_CNFG_BITS] = { 0x0FFC, 0x00, 0x00, 0x00 },
132 [BAM_IRQ_SRCS_EE] = { 0x1800, 0x00, 0x00, 0x80 },
133 [BAM_IRQ_SRCS_MSK_EE] = { 0x1804, 0x00, 0x00, 0x80 },
134 [BAM_P_CTRL] = { 0x0000, 0x80, 0x00, 0x00 },
135 [BAM_P_RST] = { 0x0004, 0x80, 0x00, 0x00 },
136 [BAM_P_HALT] = { 0x0008, 0x80, 0x00, 0x00 },
137 [BAM_P_IRQ_STTS] = { 0x0010, 0x80, 0x00, 0x00 },
138 [BAM_P_IRQ_CLR] = { 0x0014, 0x80, 0x00, 0x00 },
139 [BAM_P_IRQ_EN] = { 0x0018, 0x80, 0x00, 0x00 },
140 [BAM_P_EVNT_DEST_ADDR] = { 0x102C, 0x00, 0x40, 0x00 },
141 [BAM_P_EVNT_REG] = { 0x1018, 0x00, 0x40, 0x00 },
142 [BAM_P_SW_OFSTS] = { 0x1000, 0x00, 0x40, 0x00 },
143 [BAM_P_DATA_FIFO_ADDR] = { 0x1024, 0x00, 0x40, 0x00 },
144 [BAM_P_DESC_FIFO_ADDR] = { 0x101C, 0x00, 0x40, 0x00 },
145 [BAM_P_EVNT_GEN_TRSHLD] = { 0x1028, 0x00, 0x40, 0x00 },
146 [BAM_P_FIFO_SIZES] = { 0x1020, 0x00, 0x40, 0x00 },
149 static const struct reg_offset_data bam_v1_4_reg_info[] = {
150 [BAM_CTRL] = { 0x0000, 0x00, 0x00, 0x00 },
151 [BAM_REVISION] = { 0x0004, 0x00, 0x00, 0x00 },
152 [BAM_NUM_PIPES] = { 0x003C, 0x00, 0x00, 0x00 },
153 [BAM_DESC_CNT_TRSHLD] = { 0x0008, 0x00, 0x00, 0x00 },
154 [BAM_IRQ_SRCS] = { 0x000C, 0x00, 0x00, 0x00 },
155 [BAM_IRQ_SRCS_MSK] = { 0x0010, 0x00, 0x00, 0x00 },
156 [BAM_IRQ_SRCS_UNMASKED] = { 0x0030, 0x00, 0x00, 0x00 },
157 [BAM_IRQ_STTS] = { 0x0014, 0x00, 0x00, 0x00 },
158 [BAM_IRQ_CLR] = { 0x0018, 0x00, 0x00, 0x00 },
159 [BAM_IRQ_EN] = { 0x001C, 0x00, 0x00, 0x00 },
160 [BAM_CNFG_BITS] = { 0x007C, 0x00, 0x00, 0x00 },
161 [BAM_IRQ_SRCS_EE] = { 0x0800, 0x00, 0x00, 0x80 },
162 [BAM_IRQ_SRCS_MSK_EE] = { 0x0804, 0x00, 0x00, 0x80 },
163 [BAM_P_CTRL] = { 0x1000, 0x1000, 0x00, 0x00 },
164 [BAM_P_RST] = { 0x1004, 0x1000, 0x00, 0x00 },
165 [BAM_P_HALT] = { 0x1008, 0x1000, 0x00, 0x00 },
166 [BAM_P_IRQ_STTS] = { 0x1010, 0x1000, 0x00, 0x00 },
167 [BAM_P_IRQ_CLR] = { 0x1014, 0x1000, 0x00, 0x00 },
168 [BAM_P_IRQ_EN] = { 0x1018, 0x1000, 0x00, 0x00 },
169 [BAM_P_EVNT_DEST_ADDR] = { 0x182C, 0x00, 0x1000, 0x00 },
170 [BAM_P_EVNT_REG] = { 0x1818, 0x00, 0x1000, 0x00 },
171 [BAM_P_SW_OFSTS] = { 0x1800, 0x00, 0x1000, 0x00 },
172 [BAM_P_DATA_FIFO_ADDR] = { 0x1824, 0x00, 0x1000, 0x00 },
173 [BAM_P_DESC_FIFO_ADDR] = { 0x181C, 0x00, 0x1000, 0x00 },
174 [BAM_P_EVNT_GEN_TRSHLD] = { 0x1828, 0x00, 0x1000, 0x00 },
175 [BAM_P_FIFO_SIZES] = { 0x1820, 0x00, 0x1000, 0x00 },
178 static const struct reg_offset_data bam_v1_7_reg_info[] = {
179 [BAM_CTRL] = { 0x00000, 0x00, 0x00, 0x00 },
180 [BAM_REVISION] = { 0x01000, 0x00, 0x00, 0x00 },
181 [BAM_NUM_PIPES] = { 0x01008, 0x00, 0x00, 0x00 },
182 [BAM_DESC_CNT_TRSHLD] = { 0x00008, 0x00, 0x00, 0x00 },
183 [BAM_IRQ_SRCS] = { 0x03010, 0x00, 0x00, 0x00 },
184 [BAM_IRQ_SRCS_MSK] = { 0x03014, 0x00, 0x00, 0x00 },
185 [BAM_IRQ_SRCS_UNMASKED] = { 0x03018, 0x00, 0x00, 0x00 },
186 [BAM_IRQ_STTS] = { 0x00014, 0x00, 0x00, 0x00 },
187 [BAM_IRQ_CLR] = { 0x00018, 0x00, 0x00, 0x00 },
188 [BAM_IRQ_EN] = { 0x0001C, 0x00, 0x00, 0x00 },
189 [BAM_CNFG_BITS] = { 0x0007C, 0x00, 0x00, 0x00 },
190 [BAM_IRQ_SRCS_EE] = { 0x03000, 0x00, 0x00, 0x1000 },
191 [BAM_IRQ_SRCS_MSK_EE] = { 0x03004, 0x00, 0x00, 0x1000 },
192 [BAM_P_CTRL] = { 0x13000, 0x1000, 0x00, 0x00 },
193 [BAM_P_RST] = { 0x13004, 0x1000, 0x00, 0x00 },
194 [BAM_P_HALT] = { 0x13008, 0x1000, 0x00, 0x00 },
195 [BAM_P_IRQ_STTS] = { 0x13010, 0x1000, 0x00, 0x00 },
196 [BAM_P_IRQ_CLR] = { 0x13014, 0x1000, 0x00, 0x00 },
197 [BAM_P_IRQ_EN] = { 0x13018, 0x1000, 0x00, 0x00 },
198 [BAM_P_EVNT_DEST_ADDR] = { 0x1382C, 0x00, 0x1000, 0x00 },
199 [BAM_P_EVNT_REG] = { 0x13818, 0x00, 0x1000, 0x00 },
200 [BAM_P_SW_OFSTS] = { 0x13800, 0x00, 0x1000, 0x00 },
201 [BAM_P_DATA_FIFO_ADDR] = { 0x13824, 0x00, 0x1000, 0x00 },
202 [BAM_P_DESC_FIFO_ADDR] = { 0x1381C, 0x00, 0x1000, 0x00 },
203 [BAM_P_EVNT_GEN_TRSHLD] = { 0x13828, 0x00, 0x1000, 0x00 },
204 [BAM_P_FIFO_SIZES] = { 0x13820, 0x00, 0x1000, 0x00 },
208 #define BAM_SW_RST BIT(0)
209 #define BAM_EN BIT(1)
210 #define BAM_EN_ACCUM BIT(4)
211 #define BAM_TESTBUS_SEL_SHIFT 5
212 #define BAM_TESTBUS_SEL_MASK 0x3F
213 #define BAM_DESC_CACHE_SEL_SHIFT 13
214 #define BAM_DESC_CACHE_SEL_MASK 0x3
215 #define BAM_CACHED_DESC_STORE BIT(15)
216 #define IBC_DISABLE BIT(16)
219 #define REVISION_SHIFT 0
220 #define REVISION_MASK 0xFF
221 #define NUM_EES_SHIFT 8
222 #define NUM_EES_MASK 0xF
223 #define CE_BUFFER_SIZE BIT(13)
224 #define AXI_ACTIVE BIT(14)
225 #define USE_VMIDMT BIT(15)
226 #define SECURED BIT(16)
227 #define BAM_HAS_NO_BYPASS BIT(17)
228 #define HIGH_FREQUENCY_BAM BIT(18)
229 #define INACTIV_TMRS_EXST BIT(19)
230 #define NUM_INACTIV_TMRS BIT(20)
231 #define DESC_CACHE_DEPTH_SHIFT 21
232 #define DESC_CACHE_DEPTH_1 (0 << DESC_CACHE_DEPTH_SHIFT)
233 #define DESC_CACHE_DEPTH_2 (1 << DESC_CACHE_DEPTH_SHIFT)
234 #define DESC_CACHE_DEPTH_3 (2 << DESC_CACHE_DEPTH_SHIFT)
235 #define DESC_CACHE_DEPTH_4 (3 << DESC_CACHE_DEPTH_SHIFT)
236 #define CMD_DESC_EN BIT(23)
237 #define INACTIV_TMR_BASE_SHIFT 24
238 #define INACTIV_TMR_BASE_MASK 0xFF
241 #define BAM_NUM_PIPES_SHIFT 0
242 #define BAM_NUM_PIPES_MASK 0xFF
243 #define PERIPH_NON_PIPE_GRP_SHIFT 16
244 #define PERIPH_NON_PIP_GRP_MASK 0xFF
245 #define BAM_NON_PIPE_GRP_SHIFT 24
246 #define BAM_NON_PIPE_GRP_MASK 0xFF
249 #define BAM_PIPE_CNFG BIT(2)
250 #define BAM_FULL_PIPE BIT(11)
251 #define BAM_NO_EXT_P_RST BIT(12)
252 #define BAM_IBC_DISABLE BIT(13)
253 #define BAM_SB_CLK_REQ BIT(14)
254 #define BAM_PSM_CSW_REQ BIT(15)
255 #define BAM_PSM_P_RES BIT(16)
256 #define BAM_AU_P_RES BIT(17)
257 #define BAM_SI_P_RES BIT(18)
258 #define BAM_WB_P_RES BIT(19)
259 #define BAM_WB_BLK_CSW BIT(20)
260 #define BAM_WB_CSW_ACK_IDL BIT(21)
261 #define BAM_WB_RETR_SVPNT BIT(22)
262 #define BAM_WB_DSC_AVL_P_RST BIT(23)
263 #define BAM_REG_P_EN BIT(24)
264 #define BAM_PSM_P_HD_DATA BIT(25)
265 #define BAM_AU_ACCUMED BIT(26)
266 #define BAM_CMD_ENABLE BIT(27)
268 #define BAM_CNFG_BITS_DEFAULT (BAM_PIPE_CNFG | \
278 BAM_WB_CSW_ACK_IDL | \
279 BAM_WB_RETR_SVPNT | \
280 BAM_WB_DSC_AVL_P_RST | \
282 BAM_PSM_P_HD_DATA | \
288 #define P_DIRECTION BIT(3)
289 #define P_SYS_STRM BIT(4)
290 #define P_SYS_MODE BIT(5)
291 #define P_AUTO_EOB BIT(6)
292 #define P_AUTO_EOB_SEL_SHIFT 7
293 #define P_AUTO_EOB_SEL_512 (0 << P_AUTO_EOB_SEL_SHIFT)
294 #define P_AUTO_EOB_SEL_256 (1 << P_AUTO_EOB_SEL_SHIFT)
295 #define P_AUTO_EOB_SEL_128 (2 << P_AUTO_EOB_SEL_SHIFT)
296 #define P_AUTO_EOB_SEL_64 (3 << P_AUTO_EOB_SEL_SHIFT)
297 #define P_PREFETCH_LIMIT_SHIFT 9
298 #define P_PREFETCH_LIMIT_32 (0 << P_PREFETCH_LIMIT_SHIFT)
299 #define P_PREFETCH_LIMIT_16 (1 << P_PREFETCH_LIMIT_SHIFT)
300 #define P_PREFETCH_LIMIT_4 (2 << P_PREFETCH_LIMIT_SHIFT)
301 #define P_WRITE_NWD BIT(11)
302 #define P_LOCK_GROUP_SHIFT 16
303 #define P_LOCK_GROUP_MASK 0x1F
305 /* BAM_DESC_CNT_TRSHLD */
306 #define CNT_TRSHLD 0xffff
307 #define DEFAULT_CNT_THRSHLD 0x4
310 #define BAM_IRQ BIT(31)
311 #define P_IRQ 0x7fffffff
313 /* BAM_IRQ_SRCS_MSK */
314 #define BAM_IRQ_MSK BAM_IRQ
315 #define P_IRQ_MSK P_IRQ
318 #define BAM_TIMER_IRQ BIT(4)
319 #define BAM_EMPTY_IRQ BIT(3)
320 #define BAM_ERROR_IRQ BIT(2)
321 #define BAM_HRESP_ERR_IRQ BIT(1)
324 #define BAM_TIMER_CLR BIT(4)
325 #define BAM_EMPTY_CLR BIT(3)
326 #define BAM_ERROR_CLR BIT(2)
327 #define BAM_HRESP_ERR_CLR BIT(1)
330 #define BAM_TIMER_EN BIT(4)
331 #define BAM_EMPTY_EN BIT(3)
332 #define BAM_ERROR_EN BIT(2)
333 #define BAM_HRESP_ERR_EN BIT(1)
336 #define P_PRCSD_DESC_EN BIT(0)
337 #define P_TIMER_EN BIT(1)
338 #define P_WAKE_EN BIT(2)
339 #define P_OUT_OF_DESC_EN BIT(3)
340 #define P_ERR_EN BIT(4)
341 #define P_TRNSFR_END_EN BIT(5)
342 #define P_DEFAULT_IRQS_EN (P_PRCSD_DESC_EN | P_ERR_EN | P_TRNSFR_END_EN)
345 #define P_SW_OFSTS_MASK 0xffff
347 #define BAM_DESC_FIFO_SIZE SZ_32K
348 #define MAX_DESCRIPTORS (BAM_DESC_FIFO_SIZE / sizeof(struct bam_desc_hw) - 1)
349 #define BAM_FIFO_SIZE (SZ_32K - 8)
352 struct virt_dma_chan vc;
354 struct bam_device *bdev;
356 /* configuration from device tree */
359 struct bam_async_desc *curr_txd; /* current running dma */
361 /* runtime configuration */
362 struct dma_slave_config slave;
365 struct bam_desc_hw *fifo_virt;
366 dma_addr_t fifo_phys;
369 unsigned short head; /* start of active descriptor entries */
370 unsigned short tail; /* end of active descriptor entries */
372 unsigned int initialized; /* is the channel hw initialized? */
373 unsigned int paused; /* is the channel paused? */
374 unsigned int reconfigure; /* new slave config? */
376 struct list_head node;
379 static inline struct bam_chan *to_bam_chan(struct dma_chan *common)
381 return container_of(common, struct bam_chan, vc.chan);
387 struct dma_device common;
388 struct device_dma_parameters dma_parms;
389 struct bam_chan *channels;
392 /* execution environment ID, from DT */
394 bool controlled_remotely;
396 const struct reg_offset_data *layout;
401 /* dma start transaction tasklet */
402 struct tasklet_struct task;
406 * bam_addr - returns BAM register address
408 * @pipe: pipe instance (ignored when register doesn't have multiple instances)
409 * @reg: register enum
411 static inline void __iomem *bam_addr(struct bam_device *bdev, u32 pipe,
414 const struct reg_offset_data r = bdev->layout[reg];
416 return bdev->regs + r.base_offset +
419 r.ee_mult * bdev->ee;
423 * bam_reset_channel - Reset individual BAM DMA channel
424 * @bchan: bam channel
426 * This function resets a specific BAM channel
428 static void bam_reset_channel(struct bam_chan *bchan)
430 struct bam_device *bdev = bchan->bdev;
432 lockdep_assert_held(&bchan->vc.lock);
435 writel_relaxed(1, bam_addr(bdev, bchan->id, BAM_P_RST));
436 writel_relaxed(0, bam_addr(bdev, bchan->id, BAM_P_RST));
438 /* don't allow cpu to reorder BAM register accesses done after this */
441 /* make sure hw is initialized when channel is used the first time */
442 bchan->initialized = 0;
446 * bam_chan_init_hw - Initialize channel hardware
447 * @bchan: bam channel
449 * This function resets and initializes the BAM channel
451 static void bam_chan_init_hw(struct bam_chan *bchan,
452 enum dma_transfer_direction dir)
454 struct bam_device *bdev = bchan->bdev;
457 /* Reset the channel to clear internal state of the FIFO */
458 bam_reset_channel(bchan);
461 * write out 8 byte aligned address. We have enough space for this
462 * because we allocated 1 more descriptor (8 bytes) than we can use
464 writel_relaxed(ALIGN(bchan->fifo_phys, sizeof(struct bam_desc_hw)),
465 bam_addr(bdev, bchan->id, BAM_P_DESC_FIFO_ADDR));
466 writel_relaxed(BAM_FIFO_SIZE,
467 bam_addr(bdev, bchan->id, BAM_P_FIFO_SIZES));
469 /* enable the per pipe interrupts, enable EOT, ERR, and INT irqs */
470 writel_relaxed(P_DEFAULT_IRQS_EN,
471 bam_addr(bdev, bchan->id, BAM_P_IRQ_EN));
473 /* unmask the specific pipe and EE combo */
474 val = readl_relaxed(bam_addr(bdev, 0, BAM_IRQ_SRCS_MSK_EE));
475 val |= BIT(bchan->id);
476 writel_relaxed(val, bam_addr(bdev, 0, BAM_IRQ_SRCS_MSK_EE));
478 /* don't allow cpu to reorder the channel enable done below */
481 /* set fixed direction and mode, then enable channel */
482 val = P_EN | P_SYS_MODE;
483 if (dir == DMA_DEV_TO_MEM)
486 writel_relaxed(val, bam_addr(bdev, bchan->id, BAM_P_CTRL));
488 bchan->initialized = 1;
490 /* init FIFO pointers */
496 * bam_alloc_chan - Allocate channel resources for DMA channel.
497 * @chan: specified channel
499 * This function allocates the FIFO descriptor memory
501 static int bam_alloc_chan(struct dma_chan *chan)
503 struct bam_chan *bchan = to_bam_chan(chan);
504 struct bam_device *bdev = bchan->bdev;
506 if (bchan->fifo_virt)
509 /* allocate FIFO descriptor space, but only if necessary */
510 bchan->fifo_virt = dma_alloc_wc(bdev->dev, BAM_DESC_FIFO_SIZE,
511 &bchan->fifo_phys, GFP_KERNEL);
513 if (!bchan->fifo_virt) {
514 dev_err(bdev->dev, "Failed to allocate desc fifo\n");
522 * bam_free_chan - Frees dma resources associated with specific channel
523 * @chan: specified channel
525 * Free the allocated fifo descriptor memory and channel resources
528 static void bam_free_chan(struct dma_chan *chan)
530 struct bam_chan *bchan = to_bam_chan(chan);
531 struct bam_device *bdev = bchan->bdev;
536 ret = pm_runtime_get_sync(bdev->dev);
540 vchan_free_chan_resources(to_virt_chan(chan));
542 if (bchan->curr_txd) {
543 dev_err(bchan->bdev->dev, "Cannot free busy channel\n");
547 spin_lock_irqsave(&bchan->vc.lock, flags);
548 bam_reset_channel(bchan);
549 spin_unlock_irqrestore(&bchan->vc.lock, flags);
551 dma_free_wc(bdev->dev, BAM_DESC_FIFO_SIZE, bchan->fifo_virt,
553 bchan->fifo_virt = NULL;
555 /* mask irq for pipe/channel */
556 val = readl_relaxed(bam_addr(bdev, 0, BAM_IRQ_SRCS_MSK_EE));
557 val &= ~BIT(bchan->id);
558 writel_relaxed(val, bam_addr(bdev, 0, BAM_IRQ_SRCS_MSK_EE));
561 writel_relaxed(0, bam_addr(bdev, bchan->id, BAM_P_IRQ_EN));
564 pm_runtime_mark_last_busy(bdev->dev);
565 pm_runtime_put_autosuspend(bdev->dev);
569 * bam_slave_config - set slave configuration for channel
571 * @cfg: slave configuration
573 * Sets slave configuration for channel
576 static int bam_slave_config(struct dma_chan *chan,
577 struct dma_slave_config *cfg)
579 struct bam_chan *bchan = to_bam_chan(chan);
582 spin_lock_irqsave(&bchan->vc.lock, flag);
583 memcpy(&bchan->slave, cfg, sizeof(*cfg));
584 bchan->reconfigure = 1;
585 spin_unlock_irqrestore(&bchan->vc.lock, flag);
591 * bam_prep_slave_sg - Prep slave sg transaction
594 * @sgl: scatter gather list
595 * @sg_len: length of sg
596 * @direction: DMA transfer direction
598 * @context: transfer context (unused)
600 static struct dma_async_tx_descriptor *bam_prep_slave_sg(struct dma_chan *chan,
601 struct scatterlist *sgl, unsigned int sg_len,
602 enum dma_transfer_direction direction, unsigned long flags,
605 struct bam_chan *bchan = to_bam_chan(chan);
606 struct bam_device *bdev = bchan->bdev;
607 struct bam_async_desc *async_desc;
608 struct scatterlist *sg;
610 struct bam_desc_hw *desc;
611 unsigned int num_alloc = 0;
614 if (!is_slave_direction(direction)) {
615 dev_err(bdev->dev, "invalid dma direction\n");
619 /* calculate number of required entries */
620 for_each_sg(sgl, sg, sg_len, i)
621 num_alloc += DIV_ROUND_UP(sg_dma_len(sg), BAM_FIFO_SIZE);
623 /* allocate enough room to accomodate the number of entries */
624 async_desc = kzalloc(sizeof(*async_desc) +
625 (num_alloc * sizeof(struct bam_desc_hw)), GFP_NOWAIT);
630 if (flags & DMA_PREP_FENCE)
631 async_desc->flags |= DESC_FLAG_NWD;
633 if (flags & DMA_PREP_INTERRUPT)
634 async_desc->flags |= DESC_FLAG_EOT;
636 async_desc->flags |= DESC_FLAG_INT;
638 async_desc->num_desc = num_alloc;
639 async_desc->curr_desc = async_desc->desc;
640 async_desc->dir = direction;
642 /* fill in temporary descriptors */
643 desc = async_desc->desc;
644 for_each_sg(sgl, sg, sg_len, i) {
645 unsigned int remainder = sg_dma_len(sg);
646 unsigned int curr_offset = 0;
649 if (flags & DMA_PREP_CMD)
650 desc->flags |= cpu_to_le16(DESC_FLAG_CMD);
652 desc->addr = cpu_to_le32(sg_dma_address(sg) +
655 if (remainder > BAM_FIFO_SIZE) {
656 desc->size = cpu_to_le16(BAM_FIFO_SIZE);
657 remainder -= BAM_FIFO_SIZE;
658 curr_offset += BAM_FIFO_SIZE;
660 desc->size = cpu_to_le16(remainder);
664 async_desc->length += desc->size;
666 } while (remainder > 0);
669 return vchan_tx_prep(&bchan->vc, &async_desc->vd, flags);
677 * bam_dma_terminate_all - terminate all transactions on a channel
678 * @bchan: bam dma channel
680 * Dequeues and frees all transactions
681 * No callbacks are done
684 static int bam_dma_terminate_all(struct dma_chan *chan)
686 struct bam_chan *bchan = to_bam_chan(chan);
690 /* remove all transactions, including active transaction */
691 spin_lock_irqsave(&bchan->vc.lock, flag);
692 if (bchan->curr_txd) {
693 list_add(&bchan->curr_txd->vd.node, &bchan->vc.desc_issued);
694 bchan->curr_txd = NULL;
697 vchan_get_all_descriptors(&bchan->vc, &head);
698 spin_unlock_irqrestore(&bchan->vc.lock, flag);
700 vchan_dma_desc_free_list(&bchan->vc, &head);
706 * bam_pause - Pause DMA channel
710 static int bam_pause(struct dma_chan *chan)
712 struct bam_chan *bchan = to_bam_chan(chan);
713 struct bam_device *bdev = bchan->bdev;
717 ret = pm_runtime_get_sync(bdev->dev);
721 spin_lock_irqsave(&bchan->vc.lock, flag);
722 writel_relaxed(1, bam_addr(bdev, bchan->id, BAM_P_HALT));
724 spin_unlock_irqrestore(&bchan->vc.lock, flag);
725 pm_runtime_mark_last_busy(bdev->dev);
726 pm_runtime_put_autosuspend(bdev->dev);
732 * bam_resume - Resume DMA channel operations
736 static int bam_resume(struct dma_chan *chan)
738 struct bam_chan *bchan = to_bam_chan(chan);
739 struct bam_device *bdev = bchan->bdev;
743 ret = pm_runtime_get_sync(bdev->dev);
747 spin_lock_irqsave(&bchan->vc.lock, flag);
748 writel_relaxed(0, bam_addr(bdev, bchan->id, BAM_P_HALT));
750 spin_unlock_irqrestore(&bchan->vc.lock, flag);
751 pm_runtime_mark_last_busy(bdev->dev);
752 pm_runtime_put_autosuspend(bdev->dev);
758 * process_channel_irqs - processes the channel interrupts
759 * @bdev: bam controller
761 * This function processes the channel interrupts
764 static u32 process_channel_irqs(struct bam_device *bdev)
766 u32 i, srcs, pipe_stts;
768 struct bam_async_desc *async_desc;
770 srcs = readl_relaxed(bam_addr(bdev, 0, BAM_IRQ_SRCS_EE));
772 /* return early if no pipe/channel interrupts are present */
776 for (i = 0; i < bdev->num_channels; i++) {
777 struct bam_chan *bchan = &bdev->channels[i];
779 if (!(srcs & BIT(i)))
783 pipe_stts = readl_relaxed(bam_addr(bdev, i, BAM_P_IRQ_STTS));
785 writel_relaxed(pipe_stts, bam_addr(bdev, i, BAM_P_IRQ_CLR));
787 spin_lock_irqsave(&bchan->vc.lock, flags);
788 async_desc = bchan->curr_txd;
791 async_desc->num_desc -= async_desc->xfer_len;
792 async_desc->curr_desc += async_desc->xfer_len;
793 bchan->curr_txd = NULL;
796 bchan->head += async_desc->xfer_len;
797 bchan->head %= MAX_DESCRIPTORS;
800 * if complete, process cookie. Otherwise
801 * push back to front of desc_issued so that
802 * it gets restarted by the tasklet
804 if (!async_desc->num_desc)
805 vchan_cookie_complete(&async_desc->vd);
807 list_add(&async_desc->vd.node,
808 &bchan->vc.desc_issued);
811 spin_unlock_irqrestore(&bchan->vc.lock, flags);
818 * bam_dma_irq - irq handler for bam controller
819 * @irq: IRQ of interrupt
820 * @data: callback data
822 * IRQ handler for the bam controller
824 static irqreturn_t bam_dma_irq(int irq, void *data)
826 struct bam_device *bdev = data;
827 u32 clr_mask = 0, srcs = 0;
830 srcs |= process_channel_irqs(bdev);
832 /* kick off tasklet to start next dma transfer */
834 tasklet_schedule(&bdev->task);
836 ret = pm_runtime_get_sync(bdev->dev);
840 if (srcs & BAM_IRQ) {
841 clr_mask = readl_relaxed(bam_addr(bdev, 0, BAM_IRQ_STTS));
844 * don't allow reorder of the various accesses to the BAM
849 writel_relaxed(clr_mask, bam_addr(bdev, 0, BAM_IRQ_CLR));
852 pm_runtime_mark_last_busy(bdev->dev);
853 pm_runtime_put_autosuspend(bdev->dev);
859 * bam_tx_status - returns status of transaction
861 * @cookie: transaction cookie
862 * @txstate: DMA transaction state
864 * Return status of dma transaction
866 static enum dma_status bam_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
867 struct dma_tx_state *txstate)
869 struct bam_chan *bchan = to_bam_chan(chan);
870 struct virt_dma_desc *vd;
876 ret = dma_cookie_status(chan, cookie, txstate);
877 if (ret == DMA_COMPLETE)
881 return bchan->paused ? DMA_PAUSED : ret;
883 spin_lock_irqsave(&bchan->vc.lock, flags);
884 vd = vchan_find_desc(&bchan->vc, cookie);
886 residue = container_of(vd, struct bam_async_desc, vd)->length;
887 else if (bchan->curr_txd && bchan->curr_txd->vd.tx.cookie == cookie)
888 for (i = 0; i < bchan->curr_txd->num_desc; i++)
889 residue += bchan->curr_txd->curr_desc[i].size;
891 spin_unlock_irqrestore(&bchan->vc.lock, flags);
893 dma_set_residue(txstate, residue);
895 if (ret == DMA_IN_PROGRESS && bchan->paused)
902 * bam_apply_new_config
903 * @bchan: bam dma channel
904 * @dir: DMA direction
906 static void bam_apply_new_config(struct bam_chan *bchan,
907 enum dma_transfer_direction dir)
909 struct bam_device *bdev = bchan->bdev;
912 if (dir == DMA_DEV_TO_MEM)
913 maxburst = bchan->slave.src_maxburst;
915 maxburst = bchan->slave.dst_maxburst;
917 writel_relaxed(maxburst, bam_addr(bdev, 0, BAM_DESC_CNT_TRSHLD));
919 bchan->reconfigure = 0;
923 * bam_start_dma - start next transaction
924 * @bchan - bam dma channel
926 static void bam_start_dma(struct bam_chan *bchan)
928 struct virt_dma_desc *vd = vchan_next_desc(&bchan->vc);
929 struct bam_device *bdev = bchan->bdev;
930 struct bam_async_desc *async_desc;
931 struct bam_desc_hw *desc;
932 struct bam_desc_hw *fifo = PTR_ALIGN(bchan->fifo_virt,
933 sizeof(struct bam_desc_hw));
936 lockdep_assert_held(&bchan->vc.lock);
943 async_desc = container_of(vd, struct bam_async_desc, vd);
944 bchan->curr_txd = async_desc;
946 ret = pm_runtime_get_sync(bdev->dev);
950 /* on first use, initialize the channel hardware */
951 if (!bchan->initialized)
952 bam_chan_init_hw(bchan, async_desc->dir);
954 /* apply new slave config changes, if necessary */
955 if (bchan->reconfigure)
956 bam_apply_new_config(bchan, async_desc->dir);
958 desc = bchan->curr_txd->curr_desc;
960 if (async_desc->num_desc > MAX_DESCRIPTORS)
961 async_desc->xfer_len = MAX_DESCRIPTORS;
963 async_desc->xfer_len = async_desc->num_desc;
965 /* set any special flags on the last descriptor */
966 if (async_desc->num_desc == async_desc->xfer_len)
967 desc[async_desc->xfer_len - 1].flags |=
968 cpu_to_le16(async_desc->flags);
970 desc[async_desc->xfer_len - 1].flags |=
971 cpu_to_le16(DESC_FLAG_INT);
973 if (bchan->tail + async_desc->xfer_len > MAX_DESCRIPTORS) {
974 u32 partial = MAX_DESCRIPTORS - bchan->tail;
976 memcpy(&fifo[bchan->tail], desc,
977 partial * sizeof(struct bam_desc_hw));
978 memcpy(fifo, &desc[partial], (async_desc->xfer_len - partial) *
979 sizeof(struct bam_desc_hw));
981 memcpy(&fifo[bchan->tail], desc,
982 async_desc->xfer_len * sizeof(struct bam_desc_hw));
985 bchan->tail += async_desc->xfer_len;
986 bchan->tail %= MAX_DESCRIPTORS;
988 /* ensure descriptor writes and dma start not reordered */
990 writel_relaxed(bchan->tail * sizeof(struct bam_desc_hw),
991 bam_addr(bdev, bchan->id, BAM_P_EVNT_REG));
993 pm_runtime_mark_last_busy(bdev->dev);
994 pm_runtime_put_autosuspend(bdev->dev);
998 * dma_tasklet - DMA IRQ tasklet
999 * @data: tasklet argument (bam controller structure)
1001 * Sets up next DMA operation and then processes all completed transactions
1003 static void dma_tasklet(unsigned long data)
1005 struct bam_device *bdev = (struct bam_device *)data;
1006 struct bam_chan *bchan;
1007 unsigned long flags;
1010 /* go through the channels and kick off transactions */
1011 for (i = 0; i < bdev->num_channels; i++) {
1012 bchan = &bdev->channels[i];
1013 spin_lock_irqsave(&bchan->vc.lock, flags);
1015 if (!list_empty(&bchan->vc.desc_issued) && !bchan->curr_txd)
1016 bam_start_dma(bchan);
1017 spin_unlock_irqrestore(&bchan->vc.lock, flags);
1023 * bam_issue_pending - starts pending transactions
1024 * @chan: dma channel
1026 * Calls tasklet directly which in turn starts any pending transactions
1028 static void bam_issue_pending(struct dma_chan *chan)
1030 struct bam_chan *bchan = to_bam_chan(chan);
1031 unsigned long flags;
1033 spin_lock_irqsave(&bchan->vc.lock, flags);
1035 /* if work pending and idle, start a transaction */
1036 if (vchan_issue_pending(&bchan->vc) && !bchan->curr_txd)
1037 bam_start_dma(bchan);
1039 spin_unlock_irqrestore(&bchan->vc.lock, flags);
1043 * bam_dma_free_desc - free descriptor memory
1044 * @vd: virtual descriptor
1047 static void bam_dma_free_desc(struct virt_dma_desc *vd)
1049 struct bam_async_desc *async_desc = container_of(vd,
1050 struct bam_async_desc, vd);
1055 static struct dma_chan *bam_dma_xlate(struct of_phandle_args *dma_spec,
1058 struct bam_device *bdev = container_of(of->of_dma_data,
1059 struct bam_device, common);
1060 unsigned int request;
1062 if (dma_spec->args_count != 1)
1065 request = dma_spec->args[0];
1066 if (request >= bdev->num_channels)
1069 return dma_get_slave_channel(&(bdev->channels[request].vc.chan));
1076 * Initialization helper for global bam registers
1078 static int bam_init(struct bam_device *bdev)
1082 /* read revision and configuration information */
1083 val = readl_relaxed(bam_addr(bdev, 0, BAM_REVISION)) >> NUM_EES_SHIFT;
1084 val &= NUM_EES_MASK;
1086 /* check that configured EE is within range */
1087 if (bdev->ee >= val)
1090 val = readl_relaxed(bam_addr(bdev, 0, BAM_NUM_PIPES));
1091 bdev->num_channels = val & BAM_NUM_PIPES_MASK;
1093 if (bdev->controlled_remotely)
1097 /* after reset all pipes are disabled and idle */
1098 val = readl_relaxed(bam_addr(bdev, 0, BAM_CTRL));
1100 writel_relaxed(val, bam_addr(bdev, 0, BAM_CTRL));
1102 writel_relaxed(val, bam_addr(bdev, 0, BAM_CTRL));
1104 /* make sure previous stores are visible before enabling BAM */
1109 writel_relaxed(val, bam_addr(bdev, 0, BAM_CTRL));
1111 /* set descriptor threshhold, start with 4 bytes */
1112 writel_relaxed(DEFAULT_CNT_THRSHLD,
1113 bam_addr(bdev, 0, BAM_DESC_CNT_TRSHLD));
1115 /* Enable default set of h/w workarounds, ie all except BAM_FULL_PIPE */
1116 writel_relaxed(BAM_CNFG_BITS_DEFAULT, bam_addr(bdev, 0, BAM_CNFG_BITS));
1118 /* enable irqs for errors */
1119 writel_relaxed(BAM_ERROR_EN | BAM_HRESP_ERR_EN,
1120 bam_addr(bdev, 0, BAM_IRQ_EN));
1122 /* unmask global bam interrupt */
1123 writel_relaxed(BAM_IRQ_MSK, bam_addr(bdev, 0, BAM_IRQ_SRCS_MSK_EE));
1128 static void bam_channel_init(struct bam_device *bdev, struct bam_chan *bchan,
1134 vchan_init(&bchan->vc, &bdev->common);
1135 bchan->vc.desc_free = bam_dma_free_desc;
1138 static const struct of_device_id bam_of_match[] = {
1139 { .compatible = "qcom,bam-v1.3.0", .data = &bam_v1_3_reg_info },
1140 { .compatible = "qcom,bam-v1.4.0", .data = &bam_v1_4_reg_info },
1141 { .compatible = "qcom,bam-v1.7.0", .data = &bam_v1_7_reg_info },
1145 MODULE_DEVICE_TABLE(of, bam_of_match);
1147 static int bam_dma_probe(struct platform_device *pdev)
1149 struct bam_device *bdev;
1150 const struct of_device_id *match;
1151 struct resource *iores;
1154 bdev = devm_kzalloc(&pdev->dev, sizeof(*bdev), GFP_KERNEL);
1158 bdev->dev = &pdev->dev;
1160 match = of_match_node(bam_of_match, pdev->dev.of_node);
1162 dev_err(&pdev->dev, "Unsupported BAM module\n");
1166 bdev->layout = match->data;
1168 iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1169 bdev->regs = devm_ioremap_resource(&pdev->dev, iores);
1170 if (IS_ERR(bdev->regs))
1171 return PTR_ERR(bdev->regs);
1173 bdev->irq = platform_get_irq(pdev, 0);
1177 ret = of_property_read_u32(pdev->dev.of_node, "qcom,ee", &bdev->ee);
1179 dev_err(bdev->dev, "Execution environment unspecified\n");
1183 bdev->controlled_remotely = of_property_read_bool(pdev->dev.of_node,
1184 "qcom,controlled-remotely");
1186 bdev->bamclk = devm_clk_get(bdev->dev, "bam_clk");
1187 if (IS_ERR(bdev->bamclk))
1188 return PTR_ERR(bdev->bamclk);
1190 ret = clk_prepare_enable(bdev->bamclk);
1192 dev_err(bdev->dev, "failed to prepare/enable clock\n");
1196 ret = bam_init(bdev);
1198 goto err_disable_clk;
1200 tasklet_init(&bdev->task, dma_tasklet, (unsigned long)bdev);
1202 bdev->channels = devm_kcalloc(bdev->dev, bdev->num_channels,
1203 sizeof(*bdev->channels), GFP_KERNEL);
1205 if (!bdev->channels) {
1207 goto err_tasklet_kill;
1210 /* allocate and initialize channels */
1211 INIT_LIST_HEAD(&bdev->common.channels);
1213 for (i = 0; i < bdev->num_channels; i++)
1214 bam_channel_init(bdev, &bdev->channels[i], i);
1216 ret = devm_request_irq(bdev->dev, bdev->irq, bam_dma_irq,
1217 IRQF_TRIGGER_HIGH, "bam_dma", bdev);
1219 goto err_bam_channel_exit;
1221 /* set max dma segment size */
1222 bdev->common.dev = bdev->dev;
1223 bdev->common.dev->dma_parms = &bdev->dma_parms;
1224 ret = dma_set_max_seg_size(bdev->common.dev, BAM_FIFO_SIZE);
1226 dev_err(bdev->dev, "cannot set maximum segment size\n");
1227 goto err_bam_channel_exit;
1230 platform_set_drvdata(pdev, bdev);
1232 /* set capabilities */
1233 dma_cap_zero(bdev->common.cap_mask);
1234 dma_cap_set(DMA_SLAVE, bdev->common.cap_mask);
1236 /* initialize dmaengine apis */
1237 bdev->common.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
1238 bdev->common.residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT;
1239 bdev->common.src_addr_widths = DMA_SLAVE_BUSWIDTH_4_BYTES;
1240 bdev->common.dst_addr_widths = DMA_SLAVE_BUSWIDTH_4_BYTES;
1241 bdev->common.device_alloc_chan_resources = bam_alloc_chan;
1242 bdev->common.device_free_chan_resources = bam_free_chan;
1243 bdev->common.device_prep_slave_sg = bam_prep_slave_sg;
1244 bdev->common.device_config = bam_slave_config;
1245 bdev->common.device_pause = bam_pause;
1246 bdev->common.device_resume = bam_resume;
1247 bdev->common.device_terminate_all = bam_dma_terminate_all;
1248 bdev->common.device_issue_pending = bam_issue_pending;
1249 bdev->common.device_tx_status = bam_tx_status;
1250 bdev->common.dev = bdev->dev;
1252 ret = dma_async_device_register(&bdev->common);
1254 dev_err(bdev->dev, "failed to register dma async device\n");
1255 goto err_bam_channel_exit;
1258 ret = of_dma_controller_register(pdev->dev.of_node, bam_dma_xlate,
1261 goto err_unregister_dma;
1263 pm_runtime_irq_safe(&pdev->dev);
1264 pm_runtime_set_autosuspend_delay(&pdev->dev, BAM_DMA_AUTOSUSPEND_DELAY);
1265 pm_runtime_use_autosuspend(&pdev->dev);
1266 pm_runtime_mark_last_busy(&pdev->dev);
1267 pm_runtime_set_active(&pdev->dev);
1268 pm_runtime_enable(&pdev->dev);
1273 dma_async_device_unregister(&bdev->common);
1274 err_bam_channel_exit:
1275 for (i = 0; i < bdev->num_channels; i++)
1276 tasklet_kill(&bdev->channels[i].vc.task);
1278 tasklet_kill(&bdev->task);
1280 clk_disable_unprepare(bdev->bamclk);
1285 static int bam_dma_remove(struct platform_device *pdev)
1287 struct bam_device *bdev = platform_get_drvdata(pdev);
1290 pm_runtime_force_suspend(&pdev->dev);
1292 of_dma_controller_free(pdev->dev.of_node);
1293 dma_async_device_unregister(&bdev->common);
1295 /* mask all interrupts for this execution environment */
1296 writel_relaxed(0, bam_addr(bdev, 0, BAM_IRQ_SRCS_MSK_EE));
1298 devm_free_irq(bdev->dev, bdev->irq, bdev);
1300 for (i = 0; i < bdev->num_channels; i++) {
1301 bam_dma_terminate_all(&bdev->channels[i].vc.chan);
1302 tasklet_kill(&bdev->channels[i].vc.task);
1304 if (!bdev->channels[i].fifo_virt)
1307 dma_free_wc(bdev->dev, BAM_DESC_FIFO_SIZE,
1308 bdev->channels[i].fifo_virt,
1309 bdev->channels[i].fifo_phys);
1312 tasklet_kill(&bdev->task);
1314 clk_disable_unprepare(bdev->bamclk);
1319 static int __maybe_unused bam_dma_runtime_suspend(struct device *dev)
1321 struct bam_device *bdev = dev_get_drvdata(dev);
1323 clk_disable(bdev->bamclk);
1328 static int __maybe_unused bam_dma_runtime_resume(struct device *dev)
1330 struct bam_device *bdev = dev_get_drvdata(dev);
1333 ret = clk_enable(bdev->bamclk);
1335 dev_err(dev, "clk_enable failed: %d\n", ret);
1342 static int __maybe_unused bam_dma_suspend(struct device *dev)
1344 struct bam_device *bdev = dev_get_drvdata(dev);
1346 pm_runtime_force_suspend(dev);
1348 clk_unprepare(bdev->bamclk);
1353 static int __maybe_unused bam_dma_resume(struct device *dev)
1355 struct bam_device *bdev = dev_get_drvdata(dev);
1358 ret = clk_prepare(bdev->bamclk);
1362 pm_runtime_force_resume(dev);
1367 static const struct dev_pm_ops bam_dma_pm_ops = {
1368 SET_LATE_SYSTEM_SLEEP_PM_OPS(bam_dma_suspend, bam_dma_resume)
1369 SET_RUNTIME_PM_OPS(bam_dma_runtime_suspend, bam_dma_runtime_resume,
1373 static struct platform_driver bam_dma_driver = {
1374 .probe = bam_dma_probe,
1375 .remove = bam_dma_remove,
1377 .name = "bam-dma-engine",
1378 .pm = &bam_dma_pm_ops,
1379 .of_match_table = bam_of_match,
1383 module_platform_driver(bam_dma_driver);
1385 MODULE_AUTHOR("Andy Gross <agross@codeaurora.org>");
1386 MODULE_DESCRIPTION("QCOM BAM DMA engine driver");
1387 MODULE_LICENSE("GPL v2");