xref: /linux/drivers/net/ethernet/stmicro/stmmac/dwmac_lib.c (revision be239684b18e1cdcafcf8c7face4a2f562c745ad)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*******************************************************************************
3   Copyright (C) 2007-2009  STMicroelectronics Ltd
4 
5 
6   Author: Giuseppe Cavallaro <peppe.cavallaro@st.com>
7 *******************************************************************************/
8 
9 #include <linux/io.h>
10 #include <linux/iopoll.h>
11 #include "common.h"
12 #include "dwmac_dma.h"
13 #include "stmmac.h"
14 
15 #define GMAC_HI_REG_AE		0x80000000
16 
17 int dwmac_dma_reset(void __iomem *ioaddr)
18 {
19 	u32 value = readl(ioaddr + DMA_BUS_MODE);
20 
21 	/* DMA SW reset */
22 	value |= DMA_BUS_MODE_SFT_RESET;
23 	writel(value, ioaddr + DMA_BUS_MODE);
24 
25 	return readl_poll_timeout(ioaddr + DMA_BUS_MODE, value,
26 				 !(value & DMA_BUS_MODE_SFT_RESET),
27 				 10000, 200000);
28 }
29 
30 /* CSR1 enables the transmit DMA to check for new descriptor */
31 void dwmac_enable_dma_transmission(void __iomem *ioaddr)
32 {
33 	writel(1, ioaddr + DMA_XMT_POLL_DEMAND);
34 }
35 
36 void dwmac_enable_dma_irq(struct stmmac_priv *priv, void __iomem *ioaddr,
37 			  u32 chan, bool rx, bool tx)
38 {
39 	u32 value = readl(ioaddr + DMA_INTR_ENA);
40 
41 	if (rx)
42 		value |= DMA_INTR_DEFAULT_RX;
43 	if (tx)
44 		value |= DMA_INTR_DEFAULT_TX;
45 
46 	writel(value, ioaddr + DMA_INTR_ENA);
47 }
48 
49 void dwmac_disable_dma_irq(struct stmmac_priv *priv, void __iomem *ioaddr,
50 			   u32 chan, bool rx, bool tx)
51 {
52 	u32 value = readl(ioaddr + DMA_INTR_ENA);
53 
54 	if (rx)
55 		value &= ~DMA_INTR_DEFAULT_RX;
56 	if (tx)
57 		value &= ~DMA_INTR_DEFAULT_TX;
58 
59 	writel(value, ioaddr + DMA_INTR_ENA);
60 }
61 
62 void dwmac_dma_start_tx(struct stmmac_priv *priv, void __iomem *ioaddr,
63 			u32 chan)
64 {
65 	u32 value = readl(ioaddr + DMA_CONTROL);
66 	value |= DMA_CONTROL_ST;
67 	writel(value, ioaddr + DMA_CONTROL);
68 }
69 
70 void dwmac_dma_stop_tx(struct stmmac_priv *priv, void __iomem *ioaddr, u32 chan)
71 {
72 	u32 value = readl(ioaddr + DMA_CONTROL);
73 	value &= ~DMA_CONTROL_ST;
74 	writel(value, ioaddr + DMA_CONTROL);
75 }
76 
77 void dwmac_dma_start_rx(struct stmmac_priv *priv, void __iomem *ioaddr,
78 			u32 chan)
79 {
80 	u32 value = readl(ioaddr + DMA_CONTROL);
81 	value |= DMA_CONTROL_SR;
82 	writel(value, ioaddr + DMA_CONTROL);
83 }
84 
85 void dwmac_dma_stop_rx(struct stmmac_priv *priv, void __iomem *ioaddr, u32 chan)
86 {
87 	u32 value = readl(ioaddr + DMA_CONTROL);
88 	value &= ~DMA_CONTROL_SR;
89 	writel(value, ioaddr + DMA_CONTROL);
90 }
91 
92 #ifdef DWMAC_DMA_DEBUG
93 static void show_tx_process_state(unsigned int status)
94 {
95 	unsigned int state;
96 	state = (status & DMA_STATUS_TS_MASK) >> DMA_STATUS_TS_SHIFT;
97 
98 	switch (state) {
99 	case 0:
100 		pr_debug("- TX (Stopped): Reset or Stop command\n");
101 		break;
102 	case 1:
103 		pr_debug("- TX (Running): Fetching the Tx desc\n");
104 		break;
105 	case 2:
106 		pr_debug("- TX (Running): Waiting for end of tx\n");
107 		break;
108 	case 3:
109 		pr_debug("- TX (Running): Reading the data "
110 		       "and queuing the data into the Tx buf\n");
111 		break;
112 	case 6:
113 		pr_debug("- TX (Suspended): Tx Buff Underflow "
114 		       "or an unavailable Transmit descriptor\n");
115 		break;
116 	case 7:
117 		pr_debug("- TX (Running): Closing Tx descriptor\n");
118 		break;
119 	default:
120 		break;
121 	}
122 }
123 
124 static void show_rx_process_state(unsigned int status)
125 {
126 	unsigned int state;
127 	state = (status & DMA_STATUS_RS_MASK) >> DMA_STATUS_RS_SHIFT;
128 
129 	switch (state) {
130 	case 0:
131 		pr_debug("- RX (Stopped): Reset or Stop command\n");
132 		break;
133 	case 1:
134 		pr_debug("- RX (Running): Fetching the Rx desc\n");
135 		break;
136 	case 2:
137 		pr_debug("- RX (Running): Checking for end of pkt\n");
138 		break;
139 	case 3:
140 		pr_debug("- RX (Running): Waiting for Rx pkt\n");
141 		break;
142 	case 4:
143 		pr_debug("- RX (Suspended): Unavailable Rx buf\n");
144 		break;
145 	case 5:
146 		pr_debug("- RX (Running): Closing Rx descriptor\n");
147 		break;
148 	case 6:
149 		pr_debug("- RX(Running): Flushing the current frame"
150 		       " from the Rx buf\n");
151 		break;
152 	case 7:
153 		pr_debug("- RX (Running): Queuing the Rx frame"
154 		       " from the Rx buf into memory\n");
155 		break;
156 	default:
157 		break;
158 	}
159 }
160 #endif
161 
162 int dwmac_dma_interrupt(struct stmmac_priv *priv, void __iomem *ioaddr,
163 			struct stmmac_extra_stats *x, u32 chan, u32 dir)
164 {
165 	struct stmmac_pcpu_stats *stats = this_cpu_ptr(priv->xstats.pcpu_stats);
166 	int ret = 0;
167 	/* read the status register (CSR5) */
168 	u32 intr_status = readl(ioaddr + DMA_STATUS);
169 
170 #ifdef DWMAC_DMA_DEBUG
171 	/* Enable it to monitor DMA rx/tx status in case of critical problems */
172 	pr_debug("%s: [CSR5: 0x%08x]\n", __func__, intr_status);
173 	show_tx_process_state(intr_status);
174 	show_rx_process_state(intr_status);
175 #endif
176 
177 	if (dir == DMA_DIR_RX)
178 		intr_status &= DMA_STATUS_MSK_RX;
179 	else if (dir == DMA_DIR_TX)
180 		intr_status &= DMA_STATUS_MSK_TX;
181 
182 	/* ABNORMAL interrupts */
183 	if (unlikely(intr_status & DMA_STATUS_AIS)) {
184 		if (unlikely(intr_status & DMA_STATUS_UNF)) {
185 			ret = tx_hard_error_bump_tc;
186 			x->tx_undeflow_irq++;
187 		}
188 		if (unlikely(intr_status & DMA_STATUS_TJT))
189 			x->tx_jabber_irq++;
190 
191 		if (unlikely(intr_status & DMA_STATUS_OVF))
192 			x->rx_overflow_irq++;
193 
194 		if (unlikely(intr_status & DMA_STATUS_RU))
195 			x->rx_buf_unav_irq++;
196 		if (unlikely(intr_status & DMA_STATUS_RPS))
197 			x->rx_process_stopped_irq++;
198 		if (unlikely(intr_status & DMA_STATUS_RWT))
199 			x->rx_watchdog_irq++;
200 		if (unlikely(intr_status & DMA_STATUS_ETI))
201 			x->tx_early_irq++;
202 		if (unlikely(intr_status & DMA_STATUS_TPS)) {
203 			x->tx_process_stopped_irq++;
204 			ret = tx_hard_error;
205 		}
206 		if (unlikely(intr_status & DMA_STATUS_FBI)) {
207 			x->fatal_bus_error_irq++;
208 			ret = tx_hard_error;
209 		}
210 	}
211 	/* TX/RX NORMAL interrupts */
212 	if (likely(intr_status & DMA_STATUS_NIS)) {
213 		if (likely(intr_status & DMA_STATUS_RI)) {
214 			u32 value = readl(ioaddr + DMA_INTR_ENA);
215 			/* to schedule NAPI on real RIE event. */
216 			if (likely(value & DMA_INTR_ENA_RIE)) {
217 				u64_stats_update_begin(&stats->syncp);
218 				u64_stats_inc(&stats->rx_normal_irq_n[chan]);
219 				u64_stats_update_end(&stats->syncp);
220 				ret |= handle_rx;
221 			}
222 		}
223 		if (likely(intr_status & DMA_STATUS_TI)) {
224 			u64_stats_update_begin(&stats->syncp);
225 			u64_stats_inc(&stats->tx_normal_irq_n[chan]);
226 			u64_stats_update_end(&stats->syncp);
227 			ret |= handle_tx;
228 		}
229 		if (unlikely(intr_status & DMA_STATUS_ERI))
230 			x->rx_early_irq++;
231 	}
232 	/* Optional hardware blocks, interrupts should be disabled */
233 	if (unlikely(intr_status &
234 		     (DMA_STATUS_GPI | DMA_STATUS_GMI | DMA_STATUS_GLI)))
235 		pr_warn("%s: unexpected status %08x\n", __func__, intr_status);
236 
237 	/* Clear the interrupt by writing a logic 1 to the CSR5[15-0] */
238 	writel((intr_status & 0x1ffff), ioaddr + DMA_STATUS);
239 
240 	return ret;
241 }
242 
243 void dwmac_dma_flush_tx_fifo(void __iomem *ioaddr)
244 {
245 	u32 csr6 = readl(ioaddr + DMA_CONTROL);
246 	writel((csr6 | DMA_CONTROL_FTF), ioaddr + DMA_CONTROL);
247 
248 	do {} while ((readl(ioaddr + DMA_CONTROL) & DMA_CONTROL_FTF));
249 }
250 
251 void stmmac_set_mac_addr(void __iomem *ioaddr, const u8 addr[6],
252 			 unsigned int high, unsigned int low)
253 {
254 	unsigned long data;
255 
256 	data = (addr[5] << 8) | addr[4];
257 	/* For MAC Addr registers we have to set the Address Enable (AE)
258 	 * bit that has no effect on the High Reg 0 where the bit 31 (MO)
259 	 * is RO.
260 	 */
261 	writel(data | GMAC_HI_REG_AE, ioaddr + high);
262 	data = (addr[3] << 24) | (addr[2] << 16) | (addr[1] << 8) | addr[0];
263 	writel(data, ioaddr + low);
264 }
265 EXPORT_SYMBOL_GPL(stmmac_set_mac_addr);
266 
267 /* Enable disable MAC RX/TX */
268 void stmmac_set_mac(void __iomem *ioaddr, bool enable)
269 {
270 	u32 old_val, value;
271 
272 	old_val = readl(ioaddr + MAC_CTRL_REG);
273 	value = old_val;
274 
275 	if (enable)
276 		value |= MAC_ENABLE_RX | MAC_ENABLE_TX;
277 	else
278 		value &= ~(MAC_ENABLE_TX | MAC_ENABLE_RX);
279 
280 	if (value != old_val)
281 		writel(value, ioaddr + MAC_CTRL_REG);
282 }
283 
284 void stmmac_get_mac_addr(void __iomem *ioaddr, unsigned char *addr,
285 			 unsigned int high, unsigned int low)
286 {
287 	unsigned int hi_addr, lo_addr;
288 
289 	/* Read the MAC address from the hardware */
290 	hi_addr = readl(ioaddr + high);
291 	lo_addr = readl(ioaddr + low);
292 
293 	/* Extract the MAC address from the high and low words */
294 	addr[0] = lo_addr & 0xff;
295 	addr[1] = (lo_addr >> 8) & 0xff;
296 	addr[2] = (lo_addr >> 16) & 0xff;
297 	addr[3] = (lo_addr >> 24) & 0xff;
298 	addr[4] = hi_addr & 0xff;
299 	addr[5] = (hi_addr >> 8) & 0xff;
300 }
301 EXPORT_SYMBOL_GPL(stmmac_get_mac_addr);
302