xref: /linux/drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c (revision e5c86679d5e864947a52fb31e45a425dea3e7fa9)
1 /*
2  * This is the driver for the GMAC on-chip Ethernet controller for ST SoCs.
3  * DWC Ether MAC version 4.xx  has been used for  developing this code.
4  *
5  * This contains the functions to handle the dma.
6  *
7  * Copyright (C) 2015  STMicroelectronics Ltd
8  *
9  * This program is free software; you can redistribute it and/or modify it
10  * under the terms and conditions of the GNU General Public License,
11  * version 2, as published by the Free Software Foundation.
12  *
13  * Author: Alexandre Torgue <alexandre.torgue@st.com>
14  */
15 
16 #include <linux/io.h>
17 #include "dwmac4.h"
18 #include "dwmac4_dma.h"
19 
20 static void dwmac4_dma_axi(void __iomem *ioaddr, struct stmmac_axi *axi)
21 {
22 	u32 value = readl(ioaddr + DMA_SYS_BUS_MODE);
23 	int i;
24 
25 	pr_info("dwmac4: Master AXI performs %s burst length\n",
26 		(value & DMA_SYS_BUS_FB) ? "fixed" : "any");
27 
28 	if (axi->axi_lpi_en)
29 		value |= DMA_AXI_EN_LPI;
30 	if (axi->axi_xit_frm)
31 		value |= DMA_AXI_LPI_XIT_FRM;
32 
33 	value &= ~DMA_AXI_WR_OSR_LMT;
34 	value |= (axi->axi_wr_osr_lmt & DMA_AXI_OSR_MAX) <<
35 		 DMA_AXI_WR_OSR_LMT_SHIFT;
36 
37 	value &= ~DMA_AXI_RD_OSR_LMT;
38 	value |= (axi->axi_rd_osr_lmt & DMA_AXI_OSR_MAX) <<
39 		 DMA_AXI_RD_OSR_LMT_SHIFT;
40 
41 	/* Depending on the UNDEF bit the Master AXI will perform any burst
42 	 * length according to the BLEN programmed (by default all BLEN are
43 	 * set).
44 	 */
45 	for (i = 0; i < AXI_BLEN; i++) {
46 		switch (axi->axi_blen[i]) {
47 		case 256:
48 			value |= DMA_AXI_BLEN256;
49 			break;
50 		case 128:
51 			value |= DMA_AXI_BLEN128;
52 			break;
53 		case 64:
54 			value |= DMA_AXI_BLEN64;
55 			break;
56 		case 32:
57 			value |= DMA_AXI_BLEN32;
58 			break;
59 		case 16:
60 			value |= DMA_AXI_BLEN16;
61 			break;
62 		case 8:
63 			value |= DMA_AXI_BLEN8;
64 			break;
65 		case 4:
66 			value |= DMA_AXI_BLEN4;
67 			break;
68 		}
69 	}
70 
71 	writel(value, ioaddr + DMA_SYS_BUS_MODE);
72 }
73 
74 static void dwmac4_dma_init_channel(void __iomem *ioaddr,
75 				    struct stmmac_dma_cfg *dma_cfg,
76 				    u32 dma_tx_phy, u32 dma_rx_phy,
77 				    u32 channel)
78 {
79 	u32 value;
80 	int txpbl = dma_cfg->txpbl ?: dma_cfg->pbl;
81 	int rxpbl = dma_cfg->rxpbl ?: dma_cfg->pbl;
82 
83 	/* set PBL for each channels. Currently we affect same configuration
84 	 * on each channel
85 	 */
86 	value = readl(ioaddr + DMA_CHAN_CONTROL(channel));
87 	if (dma_cfg->pblx8)
88 		value = value | DMA_BUS_MODE_PBL;
89 	writel(value, ioaddr + DMA_CHAN_CONTROL(channel));
90 
91 	value = readl(ioaddr + DMA_CHAN_TX_CONTROL(channel));
92 	value = value | (txpbl << DMA_BUS_MODE_PBL_SHIFT);
93 	writel(value, ioaddr + DMA_CHAN_TX_CONTROL(channel));
94 
95 	value = readl(ioaddr + DMA_CHAN_RX_CONTROL(channel));
96 	value = value | (rxpbl << DMA_BUS_MODE_RPBL_SHIFT);
97 	writel(value, ioaddr + DMA_CHAN_RX_CONTROL(channel));
98 
99 	/* Mask interrupts by writing to CSR7 */
100 	writel(DMA_CHAN_INTR_DEFAULT_MASK, ioaddr + DMA_CHAN_INTR_ENA(channel));
101 
102 	writel(dma_tx_phy, ioaddr + DMA_CHAN_TX_BASE_ADDR(channel));
103 	writel(dma_rx_phy, ioaddr + DMA_CHAN_RX_BASE_ADDR(channel));
104 }
105 
106 static void dwmac4_dma_init(void __iomem *ioaddr,
107 			    struct stmmac_dma_cfg *dma_cfg,
108 			    u32 dma_tx, u32 dma_rx, int atds)
109 {
110 	u32 value = readl(ioaddr + DMA_SYS_BUS_MODE);
111 	int i;
112 
113 	/* Set the Fixed burst mode */
114 	if (dma_cfg->fixed_burst)
115 		value |= DMA_SYS_BUS_FB;
116 
117 	/* Mixed Burst has no effect when fb is set */
118 	if (dma_cfg->mixed_burst)
119 		value |= DMA_SYS_BUS_MB;
120 
121 	if (dma_cfg->aal)
122 		value |= DMA_SYS_BUS_AAL;
123 
124 	writel(value, ioaddr + DMA_SYS_BUS_MODE);
125 
126 	for (i = 0; i < DMA_CHANNEL_NB_MAX; i++)
127 		dwmac4_dma_init_channel(ioaddr, dma_cfg, dma_tx, dma_rx, i);
128 }
129 
130 static void _dwmac4_dump_dma_regs(void __iomem *ioaddr, u32 channel,
131 				  u32 *reg_space)
132 {
133 	reg_space[DMA_CHAN_CONTROL(channel) / 4] =
134 		readl(ioaddr + DMA_CHAN_CONTROL(channel));
135 	reg_space[DMA_CHAN_TX_CONTROL(channel) / 4] =
136 		readl(ioaddr + DMA_CHAN_TX_CONTROL(channel));
137 	reg_space[DMA_CHAN_RX_CONTROL(channel) / 4] =
138 		readl(ioaddr + DMA_CHAN_RX_CONTROL(channel));
139 	reg_space[DMA_CHAN_TX_BASE_ADDR(channel) / 4] =
140 		readl(ioaddr + DMA_CHAN_TX_BASE_ADDR(channel));
141 	reg_space[DMA_CHAN_RX_BASE_ADDR(channel) / 4] =
142 		readl(ioaddr + DMA_CHAN_RX_BASE_ADDR(channel));
143 	reg_space[DMA_CHAN_TX_END_ADDR(channel) / 4] =
144 		readl(ioaddr + DMA_CHAN_TX_END_ADDR(channel));
145 	reg_space[DMA_CHAN_RX_END_ADDR(channel) / 4] =
146 		readl(ioaddr + DMA_CHAN_RX_END_ADDR(channel));
147 	reg_space[DMA_CHAN_TX_RING_LEN(channel) / 4] =
148 		readl(ioaddr + DMA_CHAN_TX_RING_LEN(channel));
149 	reg_space[DMA_CHAN_RX_RING_LEN(channel) / 4] =
150 		readl(ioaddr + DMA_CHAN_RX_RING_LEN(channel));
151 	reg_space[DMA_CHAN_INTR_ENA(channel) / 4] =
152 		readl(ioaddr + DMA_CHAN_INTR_ENA(channel));
153 	reg_space[DMA_CHAN_RX_WATCHDOG(channel) / 4] =
154 		readl(ioaddr + DMA_CHAN_RX_WATCHDOG(channel));
155 	reg_space[DMA_CHAN_SLOT_CTRL_STATUS(channel) / 4] =
156 		readl(ioaddr + DMA_CHAN_SLOT_CTRL_STATUS(channel));
157 	reg_space[DMA_CHAN_CUR_TX_DESC(channel) / 4] =
158 		readl(ioaddr + DMA_CHAN_CUR_TX_DESC(channel));
159 	reg_space[DMA_CHAN_CUR_RX_DESC(channel) / 4] =
160 		readl(ioaddr + DMA_CHAN_CUR_RX_DESC(channel));
161 	reg_space[DMA_CHAN_CUR_TX_BUF_ADDR(channel) / 4] =
162 		readl(ioaddr + DMA_CHAN_CUR_TX_BUF_ADDR(channel));
163 	reg_space[DMA_CHAN_CUR_RX_BUF_ADDR(channel) / 4] =
164 		readl(ioaddr + DMA_CHAN_CUR_RX_BUF_ADDR(channel));
165 	reg_space[DMA_CHAN_STATUS(channel) / 4] =
166 		readl(ioaddr + DMA_CHAN_STATUS(channel));
167 }
168 
169 static void dwmac4_dump_dma_regs(void __iomem *ioaddr, u32 *reg_space)
170 {
171 	int i;
172 
173 	for (i = 0; i < DMA_CHANNEL_NB_MAX; i++)
174 		_dwmac4_dump_dma_regs(ioaddr, i, reg_space);
175 }
176 
177 static void dwmac4_rx_watchdog(void __iomem *ioaddr, u32 riwt)
178 {
179 	int i;
180 
181 	for (i = 0; i < DMA_CHANNEL_NB_MAX; i++)
182 		writel(riwt, ioaddr + DMA_CHAN_RX_WATCHDOG(i));
183 }
184 
185 static void dwmac4_dma_chan_op_mode(void __iomem *ioaddr, int txmode,
186 				    int rxmode, u32 channel)
187 {
188 	u32 mtl_tx_op, mtl_rx_op, mtl_rx_int;
189 
190 	/* Following code only done for channel 0, other channels not yet
191 	 * supported.
192 	 */
193 	mtl_tx_op = readl(ioaddr + MTL_CHAN_TX_OP_MODE(channel));
194 
195 	if (txmode == SF_DMA_MODE) {
196 		pr_debug("GMAC: enable TX store and forward mode\n");
197 		/* Transmit COE type 2 cannot be done in cut-through mode. */
198 		mtl_tx_op |= MTL_OP_MODE_TSF;
199 	} else {
200 		pr_debug("GMAC: disabling TX SF (threshold %d)\n", txmode);
201 		mtl_tx_op &= ~MTL_OP_MODE_TSF;
202 		mtl_tx_op &= MTL_OP_MODE_TTC_MASK;
203 		/* Set the transmit threshold */
204 		if (txmode <= 32)
205 			mtl_tx_op |= MTL_OP_MODE_TTC_32;
206 		else if (txmode <= 64)
207 			mtl_tx_op |= MTL_OP_MODE_TTC_64;
208 		else if (txmode <= 96)
209 			mtl_tx_op |= MTL_OP_MODE_TTC_96;
210 		else if (txmode <= 128)
211 			mtl_tx_op |= MTL_OP_MODE_TTC_128;
212 		else if (txmode <= 192)
213 			mtl_tx_op |= MTL_OP_MODE_TTC_192;
214 		else if (txmode <= 256)
215 			mtl_tx_op |= MTL_OP_MODE_TTC_256;
216 		else if (txmode <= 384)
217 			mtl_tx_op |= MTL_OP_MODE_TTC_384;
218 		else
219 			mtl_tx_op |= MTL_OP_MODE_TTC_512;
220 	}
221 	/* For an IP with DWC_EQOS_NUM_TXQ == 1, the fields TXQEN and TQS are RO
222 	 * with reset values: TXQEN on, TQS == DWC_EQOS_TXFIFO_SIZE.
223 	 * For an IP with DWC_EQOS_NUM_TXQ > 1, the fields TXQEN and TQS are R/W
224 	 * with reset values: TXQEN off, TQS 256 bytes.
225 	 *
226 	 * Write the bits in both cases, since it will have no effect when RO.
227 	 * For DWC_EQOS_NUM_TXQ > 1, the top bits in MTL_OP_MODE_TQS_MASK might
228 	 * be RO, however, writing the whole TQS field will result in a value
229 	 * equal to DWC_EQOS_TXFIFO_SIZE, just like for DWC_EQOS_NUM_TXQ == 1.
230 	 */
231 	mtl_tx_op |= MTL_OP_MODE_TXQEN | MTL_OP_MODE_TQS_MASK;
232 	writel(mtl_tx_op, ioaddr +  MTL_CHAN_TX_OP_MODE(channel));
233 
234 	mtl_rx_op = readl(ioaddr + MTL_CHAN_RX_OP_MODE(channel));
235 
236 	if (rxmode == SF_DMA_MODE) {
237 		pr_debug("GMAC: enable RX store and forward mode\n");
238 		mtl_rx_op |= MTL_OP_MODE_RSF;
239 	} else {
240 		pr_debug("GMAC: disable RX SF mode (threshold %d)\n", rxmode);
241 		mtl_rx_op &= ~MTL_OP_MODE_RSF;
242 		mtl_rx_op &= MTL_OP_MODE_RTC_MASK;
243 		if (rxmode <= 32)
244 			mtl_rx_op |= MTL_OP_MODE_RTC_32;
245 		else if (rxmode <= 64)
246 			mtl_rx_op |= MTL_OP_MODE_RTC_64;
247 		else if (rxmode <= 96)
248 			mtl_rx_op |= MTL_OP_MODE_RTC_96;
249 		else
250 			mtl_rx_op |= MTL_OP_MODE_RTC_128;
251 	}
252 
253 	writel(mtl_rx_op, ioaddr + MTL_CHAN_RX_OP_MODE(channel));
254 
255 	/* Enable MTL RX overflow */
256 	mtl_rx_int = readl(ioaddr + MTL_CHAN_INT_CTRL(channel));
257 	writel(mtl_rx_int | MTL_RX_OVERFLOW_INT_EN,
258 	       ioaddr + MTL_CHAN_INT_CTRL(channel));
259 }
260 
261 static void dwmac4_dma_operation_mode(void __iomem *ioaddr, int txmode,
262 				      int rxmode, int rxfifosz)
263 {
264 	/* Only Channel 0 is actually configured and used */
265 	dwmac4_dma_chan_op_mode(ioaddr, txmode, rxmode, 0);
266 }
267 
268 static void dwmac4_get_hw_feature(void __iomem *ioaddr,
269 				  struct dma_features *dma_cap)
270 {
271 	u32 hw_cap = readl(ioaddr + GMAC_HW_FEATURE0);
272 
273 	/*  MAC HW feature0 */
274 	dma_cap->mbps_10_100 = (hw_cap & GMAC_HW_FEAT_MIISEL);
275 	dma_cap->mbps_1000 = (hw_cap & GMAC_HW_FEAT_GMIISEL) >> 1;
276 	dma_cap->half_duplex = (hw_cap & GMAC_HW_FEAT_HDSEL) >> 2;
277 	dma_cap->hash_filter = (hw_cap & GMAC_HW_FEAT_VLHASH) >> 4;
278 	dma_cap->multi_addr = (hw_cap & GMAC_HW_FEAT_ADDMAC) >> 18;
279 	dma_cap->pcs = (hw_cap & GMAC_HW_FEAT_PCSSEL) >> 3;
280 	dma_cap->sma_mdio = (hw_cap & GMAC_HW_FEAT_SMASEL) >> 5;
281 	dma_cap->pmt_remote_wake_up = (hw_cap & GMAC_HW_FEAT_RWKSEL) >> 6;
282 	dma_cap->pmt_magic_frame = (hw_cap & GMAC_HW_FEAT_MGKSEL) >> 7;
283 	/* MMC */
284 	dma_cap->rmon = (hw_cap & GMAC_HW_FEAT_MMCSEL) >> 8;
285 	/* IEEE 1588-2008 */
286 	dma_cap->atime_stamp = (hw_cap & GMAC_HW_FEAT_TSSEL) >> 12;
287 	/* 802.3az - Energy-Efficient Ethernet (EEE) */
288 	dma_cap->eee = (hw_cap & GMAC_HW_FEAT_EEESEL) >> 13;
289 	/* TX and RX csum */
290 	dma_cap->tx_coe = (hw_cap & GMAC_HW_FEAT_TXCOSEL) >> 14;
291 	dma_cap->rx_coe =  (hw_cap & GMAC_HW_FEAT_RXCOESEL) >> 16;
292 
293 	/* MAC HW feature1 */
294 	hw_cap = readl(ioaddr + GMAC_HW_FEATURE1);
295 	dma_cap->av = (hw_cap & GMAC_HW_FEAT_AVSEL) >> 20;
296 	dma_cap->tsoen = (hw_cap & GMAC_HW_TSOEN) >> 18;
297 	/* MAC HW feature2 */
298 	hw_cap = readl(ioaddr + GMAC_HW_FEATURE2);
299 	/* TX and RX number of channels */
300 	dma_cap->number_rx_channel =
301 		((hw_cap & GMAC_HW_FEAT_RXCHCNT) >> 12) + 1;
302 	dma_cap->number_tx_channel =
303 		((hw_cap & GMAC_HW_FEAT_TXCHCNT) >> 18) + 1;
304 	/* TX and RX number of queues */
305 	dma_cap->number_rx_queues =
306 		((hw_cap & GMAC_HW_FEAT_RXQCNT) >> 0) + 1;
307 	dma_cap->number_tx_queues =
308 		((hw_cap & GMAC_HW_FEAT_TXQCNT) >> 6) + 1;
309 
310 	/* IEEE 1588-2002 */
311 	dma_cap->time_stamp = 0;
312 }
313 
314 /* Enable/disable TSO feature and set MSS */
315 static void dwmac4_enable_tso(void __iomem *ioaddr, bool en, u32 chan)
316 {
317 	u32 value;
318 
319 	if (en) {
320 		/* enable TSO */
321 		value = readl(ioaddr + DMA_CHAN_TX_CONTROL(chan));
322 		writel(value | DMA_CONTROL_TSE,
323 		       ioaddr + DMA_CHAN_TX_CONTROL(chan));
324 	} else {
325 		/* enable TSO */
326 		value = readl(ioaddr + DMA_CHAN_TX_CONTROL(chan));
327 		writel(value & ~DMA_CONTROL_TSE,
328 		       ioaddr + DMA_CHAN_TX_CONTROL(chan));
329 	}
330 }
331 
332 const struct stmmac_dma_ops dwmac4_dma_ops = {
333 	.reset = dwmac4_dma_reset,
334 	.init = dwmac4_dma_init,
335 	.axi = dwmac4_dma_axi,
336 	.dump_regs = dwmac4_dump_dma_regs,
337 	.dma_mode = dwmac4_dma_operation_mode,
338 	.enable_dma_irq = dwmac4_enable_dma_irq,
339 	.disable_dma_irq = dwmac4_disable_dma_irq,
340 	.start_tx = dwmac4_dma_start_tx,
341 	.stop_tx = dwmac4_dma_stop_tx,
342 	.start_rx = dwmac4_dma_start_rx,
343 	.stop_rx = dwmac4_dma_stop_rx,
344 	.dma_interrupt = dwmac4_dma_interrupt,
345 	.get_hw_feature = dwmac4_get_hw_feature,
346 	.rx_watchdog = dwmac4_rx_watchdog,
347 	.set_rx_ring_len = dwmac4_set_rx_ring_len,
348 	.set_tx_ring_len = dwmac4_set_tx_ring_len,
349 	.set_rx_tail_ptr = dwmac4_set_rx_tail_ptr,
350 	.set_tx_tail_ptr = dwmac4_set_tx_tail_ptr,
351 	.enable_tso = dwmac4_enable_tso,
352 };
353 
354 const struct stmmac_dma_ops dwmac410_dma_ops = {
355 	.reset = dwmac4_dma_reset,
356 	.init = dwmac4_dma_init,
357 	.axi = dwmac4_dma_axi,
358 	.dump_regs = dwmac4_dump_dma_regs,
359 	.dma_mode = dwmac4_dma_operation_mode,
360 	.enable_dma_irq = dwmac410_enable_dma_irq,
361 	.disable_dma_irq = dwmac4_disable_dma_irq,
362 	.start_tx = dwmac4_dma_start_tx,
363 	.stop_tx = dwmac4_dma_stop_tx,
364 	.start_rx = dwmac4_dma_start_rx,
365 	.stop_rx = dwmac4_dma_stop_rx,
366 	.dma_interrupt = dwmac4_dma_interrupt,
367 	.get_hw_feature = dwmac4_get_hw_feature,
368 	.rx_watchdog = dwmac4_rx_watchdog,
369 	.set_rx_ring_len = dwmac4_set_rx_ring_len,
370 	.set_tx_ring_len = dwmac4_set_tx_ring_len,
371 	.set_rx_tail_ptr = dwmac4_set_rx_tail_ptr,
372 	.set_tx_tail_ptr = dwmac4_set_tx_tail_ptr,
373 	.enable_tso = dwmac4_enable_tso,
374 };
375