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 |= (axi->axi_wr_osr_lmt & DMA_AXI_OSR_MAX) <<
34 		 DMA_AXI_WR_OSR_LMT_SHIFT;
35 
36 	value |= (axi->axi_rd_osr_lmt & DMA_AXI_OSR_MAX) <<
37 		 DMA_AXI_RD_OSR_LMT_SHIFT;
38 
39 	/* Depending on the UNDEF bit the Master AXI will perform any burst
40 	 * length according to the BLEN programmed (by default all BLEN are
41 	 * set).
42 	 */
43 	for (i = 0; i < AXI_BLEN; i++) {
44 		switch (axi->axi_blen[i]) {
45 		case 256:
46 			value |= DMA_AXI_BLEN256;
47 			break;
48 		case 128:
49 			value |= DMA_AXI_BLEN128;
50 			break;
51 		case 64:
52 			value |= DMA_AXI_BLEN64;
53 			break;
54 		case 32:
55 			value |= DMA_AXI_BLEN32;
56 			break;
57 		case 16:
58 			value |= DMA_AXI_BLEN16;
59 			break;
60 		case 8:
61 			value |= DMA_AXI_BLEN8;
62 			break;
63 		case 4:
64 			value |= DMA_AXI_BLEN4;
65 			break;
66 		}
67 	}
68 
69 	writel(value, ioaddr + DMA_SYS_BUS_MODE);
70 }
71 
72 static void dwmac4_dma_init_channel(void __iomem *ioaddr, int pbl,
73 				    u32 dma_tx_phy, u32 dma_rx_phy,
74 				    u32 channel)
75 {
76 	u32 value;
77 
78 	/* set PBL for each channels. Currently we affect same configuration
79 	 * on each channel
80 	 */
81 	value = readl(ioaddr + DMA_CHAN_CONTROL(channel));
82 	value = value | DMA_BUS_MODE_PBL;
83 	writel(value, ioaddr + DMA_CHAN_CONTROL(channel));
84 
85 	value = readl(ioaddr + DMA_CHAN_TX_CONTROL(channel));
86 	value = value | (pbl << DMA_BUS_MODE_PBL_SHIFT);
87 	writel(value, ioaddr + DMA_CHAN_TX_CONTROL(channel));
88 
89 	value = readl(ioaddr + DMA_CHAN_RX_CONTROL(channel));
90 	value = value | (pbl << DMA_BUS_MODE_RPBL_SHIFT);
91 	writel(value, ioaddr + DMA_CHAN_RX_CONTROL(channel));
92 
93 	/* Mask interrupts by writing to CSR7 */
94 	writel(DMA_CHAN_INTR_DEFAULT_MASK, ioaddr + DMA_CHAN_INTR_ENA(channel));
95 
96 	writel(dma_tx_phy, ioaddr + DMA_CHAN_TX_BASE_ADDR(channel));
97 	writel(dma_rx_phy, ioaddr + DMA_CHAN_RX_BASE_ADDR(channel));
98 }
99 
100 static void dwmac4_dma_init(void __iomem *ioaddr, int pbl, int fb, int mb,
101 			    int aal, u32 dma_tx, u32 dma_rx, int atds)
102 {
103 	u32 value = readl(ioaddr + DMA_SYS_BUS_MODE);
104 	int i;
105 
106 	/* Set the Fixed burst mode */
107 	if (fb)
108 		value |= DMA_SYS_BUS_FB;
109 
110 	/* Mixed Burst has no effect when fb is set */
111 	if (mb)
112 		value |= DMA_SYS_BUS_MB;
113 
114 	if (aal)
115 		value |= DMA_SYS_BUS_AAL;
116 
117 	writel(value, ioaddr + DMA_SYS_BUS_MODE);
118 
119 	for (i = 0; i < DMA_CHANNEL_NB_MAX; i++)
120 		dwmac4_dma_init_channel(ioaddr, pbl, dma_tx, dma_rx, i);
121 }
122 
123 static void _dwmac4_dump_dma_regs(void __iomem *ioaddr, u32 channel)
124 {
125 	pr_debug(" Channel %d\n", channel);
126 	pr_debug("\tDMA_CHAN_CONTROL, offset: 0x%x, val: 0x%x\n", 0,
127 		 readl(ioaddr + DMA_CHAN_CONTROL(channel)));
128 	pr_debug("\tDMA_CHAN_TX_CONTROL, offset: 0x%x, val: 0x%x\n", 0x4,
129 		 readl(ioaddr + DMA_CHAN_TX_CONTROL(channel)));
130 	pr_debug("\tDMA_CHAN_RX_CONTROL, offset: 0x%x, val: 0x%x\n", 0x8,
131 		 readl(ioaddr + DMA_CHAN_RX_CONTROL(channel)));
132 	pr_debug("\tDMA_CHAN_TX_BASE_ADDR, offset: 0x%x, val: 0x%x\n", 0x14,
133 		 readl(ioaddr + DMA_CHAN_TX_BASE_ADDR(channel)));
134 	pr_debug("\tDMA_CHAN_RX_BASE_ADDR, offset: 0x%x, val: 0x%x\n", 0x1c,
135 		 readl(ioaddr + DMA_CHAN_RX_BASE_ADDR(channel)));
136 	pr_debug("\tDMA_CHAN_TX_END_ADDR, offset: 0x%x, val: 0x%x\n", 0x20,
137 		 readl(ioaddr + DMA_CHAN_TX_END_ADDR(channel)));
138 	pr_debug("\tDMA_CHAN_RX_END_ADDR, offset: 0x%x, val: 0x%x\n", 0x28,
139 		 readl(ioaddr + DMA_CHAN_RX_END_ADDR(channel)));
140 	pr_debug("\tDMA_CHAN_TX_RING_LEN, offset: 0x%x, val: 0x%x\n", 0x2c,
141 		 readl(ioaddr + DMA_CHAN_TX_RING_LEN(channel)));
142 	pr_debug("\tDMA_CHAN_RX_RING_LEN, offset: 0x%x, val: 0x%x\n", 0x30,
143 		 readl(ioaddr + DMA_CHAN_RX_RING_LEN(channel)));
144 	pr_debug("\tDMA_CHAN_INTR_ENA, offset: 0x%x, val: 0x%x\n", 0x34,
145 		 readl(ioaddr + DMA_CHAN_INTR_ENA(channel)));
146 	pr_debug("\tDMA_CHAN_RX_WATCHDOG, offset: 0x%x, val: 0x%x\n", 0x38,
147 		 readl(ioaddr + DMA_CHAN_RX_WATCHDOG(channel)));
148 	pr_debug("\tDMA_CHAN_SLOT_CTRL_STATUS, offset: 0x%x, val: 0x%x\n", 0x3c,
149 		 readl(ioaddr + DMA_CHAN_SLOT_CTRL_STATUS(channel)));
150 	pr_debug("\tDMA_CHAN_CUR_TX_DESC, offset: 0x%x, val: 0x%x\n", 0x44,
151 		 readl(ioaddr + DMA_CHAN_CUR_TX_DESC(channel)));
152 	pr_debug("\tDMA_CHAN_CUR_RX_DESC, offset: 0x%x, val: 0x%x\n", 0x4c,
153 		 readl(ioaddr + DMA_CHAN_CUR_RX_DESC(channel)));
154 	pr_debug("\tDMA_CHAN_CUR_TX_BUF_ADDR, offset: 0x%x, val: 0x%x\n", 0x54,
155 		 readl(ioaddr + DMA_CHAN_CUR_TX_BUF_ADDR(channel)));
156 	pr_debug("\tDMA_CHAN_CUR_RX_BUF_ADDR, offset: 0x%x, val: 0x%x\n", 0x5c,
157 		 readl(ioaddr + DMA_CHAN_CUR_RX_BUF_ADDR(channel)));
158 	pr_debug("\tDMA_CHAN_STATUS, offset: 0x%x, val: 0x%x\n", 0x60,
159 		 readl(ioaddr + DMA_CHAN_STATUS(channel)));
160 }
161 
162 static void dwmac4_dump_dma_regs(void __iomem *ioaddr)
163 {
164 	int i;
165 
166 	pr_debug(" GMAC4 DMA registers\n");
167 
168 	for (i = 0; i < DMA_CHANNEL_NB_MAX; i++)
169 		_dwmac4_dump_dma_regs(ioaddr, i);
170 }
171 
172 static void dwmac4_rx_watchdog(void __iomem *ioaddr, u32 riwt)
173 {
174 	int i;
175 
176 	for (i = 0; i < DMA_CHANNEL_NB_MAX; i++)
177 		writel(riwt, ioaddr + DMA_CHAN_RX_WATCHDOG(i));
178 }
179 
180 static void dwmac4_dma_chan_op_mode(void __iomem *ioaddr, int txmode,
181 				    int rxmode, u32 channel)
182 {
183 	u32 mtl_tx_op, mtl_rx_op, mtl_rx_int;
184 
185 	/* Following code only done for channel 0, other channels not yet
186 	 * supported.
187 	 */
188 	mtl_tx_op = readl(ioaddr + MTL_CHAN_TX_OP_MODE(channel));
189 
190 	if (txmode == SF_DMA_MODE) {
191 		pr_debug("GMAC: enable TX store and forward mode\n");
192 		/* Transmit COE type 2 cannot be done in cut-through mode. */
193 		mtl_tx_op |= MTL_OP_MODE_TSF;
194 	} else {
195 		pr_debug("GMAC: disabling TX SF (threshold %d)\n", txmode);
196 		mtl_tx_op &= ~MTL_OP_MODE_TSF;
197 		mtl_tx_op &= MTL_OP_MODE_TTC_MASK;
198 		/* Set the transmit threshold */
199 		if (txmode <= 32)
200 			mtl_tx_op |= MTL_OP_MODE_TTC_32;
201 		else if (txmode <= 64)
202 			mtl_tx_op |= MTL_OP_MODE_TTC_64;
203 		else if (txmode <= 96)
204 			mtl_tx_op |= MTL_OP_MODE_TTC_96;
205 		else if (txmode <= 128)
206 			mtl_tx_op |= MTL_OP_MODE_TTC_128;
207 		else if (txmode <= 192)
208 			mtl_tx_op |= MTL_OP_MODE_TTC_192;
209 		else if (txmode <= 256)
210 			mtl_tx_op |= MTL_OP_MODE_TTC_256;
211 		else if (txmode <= 384)
212 			mtl_tx_op |= MTL_OP_MODE_TTC_384;
213 		else
214 			mtl_tx_op |= MTL_OP_MODE_TTC_512;
215 	}
216 
217 	writel(mtl_tx_op, ioaddr +  MTL_CHAN_TX_OP_MODE(channel));
218 
219 	mtl_rx_op = readl(ioaddr + MTL_CHAN_RX_OP_MODE(channel));
220 
221 	if (rxmode == SF_DMA_MODE) {
222 		pr_debug("GMAC: enable RX store and forward mode\n");
223 		mtl_rx_op |= MTL_OP_MODE_RSF;
224 	} else {
225 		pr_debug("GMAC: disable RX SF mode (threshold %d)\n", rxmode);
226 		mtl_rx_op &= ~MTL_OP_MODE_RSF;
227 		mtl_rx_op &= MTL_OP_MODE_RTC_MASK;
228 		if (rxmode <= 32)
229 			mtl_rx_op |= MTL_OP_MODE_RTC_32;
230 		else if (rxmode <= 64)
231 			mtl_rx_op |= MTL_OP_MODE_RTC_64;
232 		else if (rxmode <= 96)
233 			mtl_rx_op |= MTL_OP_MODE_RTC_96;
234 		else
235 			mtl_rx_op |= MTL_OP_MODE_RTC_128;
236 	}
237 
238 	writel(mtl_rx_op, ioaddr + MTL_CHAN_RX_OP_MODE(channel));
239 
240 	/* Enable MTL RX overflow */
241 	mtl_rx_int = readl(ioaddr + MTL_CHAN_INT_CTRL(channel));
242 	writel(mtl_rx_int | MTL_RX_OVERFLOW_INT_EN,
243 	       ioaddr + MTL_CHAN_INT_CTRL(channel));
244 }
245 
246 static void dwmac4_dma_operation_mode(void __iomem *ioaddr, int txmode,
247 				      int rxmode, int rxfifosz)
248 {
249 	/* Only Channel 0 is actually configured and used */
250 	dwmac4_dma_chan_op_mode(ioaddr, txmode, rxmode, 0);
251 }
252 
253 static void dwmac4_get_hw_feature(void __iomem *ioaddr,
254 				  struct dma_features *dma_cap)
255 {
256 	u32 hw_cap = readl(ioaddr + GMAC_HW_FEATURE0);
257 
258 	/*  MAC HW feature0 */
259 	dma_cap->mbps_10_100 = (hw_cap & GMAC_HW_FEAT_MIISEL);
260 	dma_cap->mbps_1000 = (hw_cap & GMAC_HW_FEAT_GMIISEL) >> 1;
261 	dma_cap->half_duplex = (hw_cap & GMAC_HW_FEAT_HDSEL) >> 2;
262 	dma_cap->hash_filter = (hw_cap & GMAC_HW_FEAT_VLHASH) >> 4;
263 	dma_cap->multi_addr = (hw_cap & GMAC_HW_FEAT_ADDMAC) >> 18;
264 	dma_cap->pcs = (hw_cap & GMAC_HW_FEAT_PCSSEL) >> 3;
265 	dma_cap->sma_mdio = (hw_cap & GMAC_HW_FEAT_SMASEL) >> 5;
266 	dma_cap->pmt_remote_wake_up = (hw_cap & GMAC_HW_FEAT_RWKSEL) >> 6;
267 	dma_cap->pmt_magic_frame = (hw_cap & GMAC_HW_FEAT_MGKSEL) >> 7;
268 	/* MMC */
269 	dma_cap->rmon = (hw_cap & GMAC_HW_FEAT_MMCSEL) >> 8;
270 	/* IEEE 1588-2008 */
271 	dma_cap->atime_stamp = (hw_cap & GMAC_HW_FEAT_TSSEL) >> 12;
272 	/* 802.3az - Energy-Efficient Ethernet (EEE) */
273 	dma_cap->eee = (hw_cap & GMAC_HW_FEAT_EEESEL) >> 13;
274 	/* TX and RX csum */
275 	dma_cap->tx_coe = (hw_cap & GMAC_HW_FEAT_TXCOSEL) >> 14;
276 	dma_cap->rx_coe =  (hw_cap & GMAC_HW_FEAT_RXCOESEL) >> 16;
277 
278 	/* MAC HW feature1 */
279 	hw_cap = readl(ioaddr + GMAC_HW_FEATURE1);
280 	dma_cap->av = (hw_cap & GMAC_HW_FEAT_AVSEL) >> 20;
281 	dma_cap->tsoen = (hw_cap & GMAC_HW_TSOEN) >> 18;
282 	/* MAC HW feature2 */
283 	hw_cap = readl(ioaddr + GMAC_HW_FEATURE2);
284 	/* TX and RX number of channels */
285 	dma_cap->number_rx_channel =
286 		((hw_cap & GMAC_HW_FEAT_RXCHCNT) >> 12) + 1;
287 	dma_cap->number_tx_channel =
288 		((hw_cap & GMAC_HW_FEAT_TXCHCNT) >> 18) + 1;
289 
290 	/* IEEE 1588-2002 */
291 	dma_cap->time_stamp = 0;
292 }
293 
294 /* Enable/disable TSO feature and set MSS */
295 static void dwmac4_enable_tso(void __iomem *ioaddr, bool en, u32 chan)
296 {
297 	u32 value;
298 
299 	if (en) {
300 		/* enable TSO */
301 		value = readl(ioaddr + DMA_CHAN_TX_CONTROL(chan));
302 		writel(value | DMA_CONTROL_TSE,
303 		       ioaddr + DMA_CHAN_TX_CONTROL(chan));
304 	} else {
305 		/* enable TSO */
306 		value = readl(ioaddr + DMA_CHAN_TX_CONTROL(chan));
307 		writel(value & ~DMA_CONTROL_TSE,
308 		       ioaddr + DMA_CHAN_TX_CONTROL(chan));
309 	}
310 }
311 
312 const struct stmmac_dma_ops dwmac4_dma_ops = {
313 	.reset = dwmac4_dma_reset,
314 	.init = dwmac4_dma_init,
315 	.axi = dwmac4_dma_axi,
316 	.dump_regs = dwmac4_dump_dma_regs,
317 	.dma_mode = dwmac4_dma_operation_mode,
318 	.enable_dma_irq = dwmac4_enable_dma_irq,
319 	.disable_dma_irq = dwmac4_disable_dma_irq,
320 	.start_tx = dwmac4_dma_start_tx,
321 	.stop_tx = dwmac4_dma_stop_tx,
322 	.start_rx = dwmac4_dma_start_rx,
323 	.stop_rx = dwmac4_dma_stop_rx,
324 	.dma_interrupt = dwmac4_dma_interrupt,
325 	.get_hw_feature = dwmac4_get_hw_feature,
326 	.rx_watchdog = dwmac4_rx_watchdog,
327 	.set_rx_ring_len = dwmac4_set_rx_ring_len,
328 	.set_tx_ring_len = dwmac4_set_tx_ring_len,
329 	.set_rx_tail_ptr = dwmac4_set_rx_tail_ptr,
330 	.set_tx_tail_ptr = dwmac4_set_tx_tail_ptr,
331 	.enable_tso = dwmac4_enable_tso,
332 };
333 
334 const struct stmmac_dma_ops dwmac410_dma_ops = {
335 	.reset = dwmac4_dma_reset,
336 	.init = dwmac4_dma_init,
337 	.axi = dwmac4_dma_axi,
338 	.dump_regs = dwmac4_dump_dma_regs,
339 	.dma_mode = dwmac4_dma_operation_mode,
340 	.enable_dma_irq = dwmac410_enable_dma_irq,
341 	.disable_dma_irq = dwmac4_disable_dma_irq,
342 	.start_tx = dwmac4_dma_start_tx,
343 	.stop_tx = dwmac4_dma_stop_tx,
344 	.start_rx = dwmac4_dma_start_rx,
345 	.stop_rx = dwmac4_dma_stop_rx,
346 	.dma_interrupt = dwmac4_dma_interrupt,
347 	.get_hw_feature = dwmac4_get_hw_feature,
348 	.rx_watchdog = dwmac4_rx_watchdog,
349 	.set_rx_ring_len = dwmac4_set_rx_ring_len,
350 	.set_tx_ring_len = dwmac4_set_tx_ring_len,
351 	.set_rx_tail_ptr = dwmac4_set_rx_tail_ptr,
352 	.set_tx_tail_ptr = dwmac4_set_tx_tail_ptr,
353 	.enable_tso = dwmac4_enable_tso,
354 };
355