1 /*******************************************************************************
2   Copyright (C) 2007-2009  STMicroelectronics Ltd
3 
4   This program is free software; you can redistribute it and/or modify it
5   under the terms and conditions of the GNU General Public License,
6   version 2, as published by the Free Software Foundation.
7 
8   This program is distributed in the hope it will be useful, but WITHOUT
9   ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10   FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
11   more details.
12 
13   You should have received a copy of the GNU General Public License along with
14   this program; if not, write to the Free Software Foundation, Inc.,
15   51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
16 
17   The full GNU General Public License is included in this distribution in
18   the file called "COPYING".
19 
20   Author: Giuseppe Cavallaro <peppe.cavallaro@st.com>
21 *******************************************************************************/
22 
23 #include <linux/io.h>
24 #include "common.h"
25 #include "dwmac_dma.h"
26 
27 #define GMAC_HI_REG_AE		0x80000000
28 
29 int dwmac_dma_reset(void __iomem *ioaddr)
30 {
31 	u32 value = readl(ioaddr + DMA_BUS_MODE);
32 	int limit;
33 
34 	/* DMA SW reset */
35 	value |= DMA_BUS_MODE_SFT_RESET;
36 	writel(value, ioaddr + DMA_BUS_MODE);
37 	limit = 10;
38 	while (limit--) {
39 		if (!(readl(ioaddr + DMA_BUS_MODE) & DMA_BUS_MODE_SFT_RESET))
40 			break;
41 		mdelay(10);
42 	}
43 
44 	if (limit < 0)
45 		return -EBUSY;
46 
47 	return 0;
48 }
49 
50 /* CSR1 enables the transmit DMA to check for new descriptor */
51 void dwmac_enable_dma_transmission(void __iomem *ioaddr)
52 {
53 	writel(1, ioaddr + DMA_XMT_POLL_DEMAND);
54 }
55 
56 void dwmac_enable_dma_irq(void __iomem *ioaddr)
57 {
58 	writel(DMA_INTR_DEFAULT_MASK, ioaddr + DMA_INTR_ENA);
59 }
60 
61 void dwmac_disable_dma_irq(void __iomem *ioaddr)
62 {
63 	writel(0, ioaddr + DMA_INTR_ENA);
64 }
65 
66 void dwmac_dma_start_tx(void __iomem *ioaddr)
67 {
68 	u32 value = readl(ioaddr + DMA_CONTROL);
69 	value |= DMA_CONTROL_ST;
70 	writel(value, ioaddr + DMA_CONTROL);
71 }
72 
73 void dwmac_dma_stop_tx(void __iomem *ioaddr)
74 {
75 	u32 value = readl(ioaddr + DMA_CONTROL);
76 	value &= ~DMA_CONTROL_ST;
77 	writel(value, ioaddr + DMA_CONTROL);
78 }
79 
80 void dwmac_dma_start_rx(void __iomem *ioaddr)
81 {
82 	u32 value = readl(ioaddr + DMA_CONTROL);
83 	value |= DMA_CONTROL_SR;
84 	writel(value, ioaddr + DMA_CONTROL);
85 }
86 
87 void dwmac_dma_stop_rx(void __iomem *ioaddr)
88 {
89 	u32 value = readl(ioaddr + DMA_CONTROL);
90 	value &= ~DMA_CONTROL_SR;
91 	writel(value, ioaddr + DMA_CONTROL);
92 }
93 
94 #ifdef DWMAC_DMA_DEBUG
95 static void show_tx_process_state(unsigned int status)
96 {
97 	unsigned int state;
98 	state = (status & DMA_STATUS_TS_MASK) >> DMA_STATUS_TS_SHIFT;
99 
100 	switch (state) {
101 	case 0:
102 		pr_debug("- TX (Stopped): Reset or Stop command\n");
103 		break;
104 	case 1:
105 		pr_debug("- TX (Running):Fetching the Tx desc\n");
106 		break;
107 	case 2:
108 		pr_debug("- TX (Running): Waiting for end of tx\n");
109 		break;
110 	case 3:
111 		pr_debug("- TX (Running): Reading the data "
112 		       "and queuing the data into the Tx buf\n");
113 		break;
114 	case 6:
115 		pr_debug("- TX (Suspended): Tx Buff Underflow "
116 		       "or an unavailable Transmit descriptor\n");
117 		break;
118 	case 7:
119 		pr_debug("- TX (Running): Closing Tx descriptor\n");
120 		break;
121 	default:
122 		break;
123 	}
124 }
125 
126 static void show_rx_process_state(unsigned int status)
127 {
128 	unsigned int state;
129 	state = (status & DMA_STATUS_RS_MASK) >> DMA_STATUS_RS_SHIFT;
130 
131 	switch (state) {
132 	case 0:
133 		pr_debug("- RX (Stopped): Reset or Stop command\n");
134 		break;
135 	case 1:
136 		pr_debug("- RX (Running): Fetching the Rx desc\n");
137 		break;
138 	case 2:
139 		pr_debug("- RX (Running):Checking for end of pkt\n");
140 		break;
141 	case 3:
142 		pr_debug("- RX (Running): Waiting for Rx pkt\n");
143 		break;
144 	case 4:
145 		pr_debug("- RX (Suspended): Unavailable Rx buf\n");
146 		break;
147 	case 5:
148 		pr_debug("- RX (Running): Closing Rx descriptor\n");
149 		break;
150 	case 6:
151 		pr_debug("- RX(Running): Flushing the current frame"
152 		       " from the Rx buf\n");
153 		break;
154 	case 7:
155 		pr_debug("- RX (Running): Queuing the Rx frame"
156 		       " from the Rx buf into memory\n");
157 		break;
158 	default:
159 		break;
160 	}
161 }
162 #endif
163 
164 int dwmac_dma_interrupt(void __iomem *ioaddr,
165 			struct stmmac_extra_stats *x)
166 {
167 	int ret = 0;
168 	/* read the status register (CSR5) */
169 	u32 intr_status = readl(ioaddr + DMA_STATUS);
170 
171 #ifdef DWMAC_DMA_DEBUG
172 	/* Enable it to monitor DMA rx/tx status in case of critical problems */
173 	pr_debug("%s: [CSR5: 0x%08x]\n", __func__, intr_status);
174 	show_tx_process_state(intr_status);
175 	show_rx_process_state(intr_status);
176 #endif
177 	/* ABNORMAL interrupts */
178 	if (unlikely(intr_status & DMA_STATUS_AIS)) {
179 		if (unlikely(intr_status & DMA_STATUS_UNF)) {
180 			ret = tx_hard_error_bump_tc;
181 			x->tx_undeflow_irq++;
182 		}
183 		if (unlikely(intr_status & DMA_STATUS_TJT))
184 			x->tx_jabber_irq++;
185 
186 		if (unlikely(intr_status & DMA_STATUS_OVF))
187 			x->rx_overflow_irq++;
188 
189 		if (unlikely(intr_status & DMA_STATUS_RU))
190 			x->rx_buf_unav_irq++;
191 		if (unlikely(intr_status & DMA_STATUS_RPS))
192 			x->rx_process_stopped_irq++;
193 		if (unlikely(intr_status & DMA_STATUS_RWT))
194 			x->rx_watchdog_irq++;
195 		if (unlikely(intr_status & DMA_STATUS_ETI))
196 			x->tx_early_irq++;
197 		if (unlikely(intr_status & DMA_STATUS_TPS)) {
198 			x->tx_process_stopped_irq++;
199 			ret = tx_hard_error;
200 		}
201 		if (unlikely(intr_status & DMA_STATUS_FBI)) {
202 			x->fatal_bus_error_irq++;
203 			ret = tx_hard_error;
204 		}
205 	}
206 	/* TX/RX NORMAL interrupts */
207 	if (likely(intr_status & DMA_STATUS_NIS)) {
208 		x->normal_irq_n++;
209 		if (likely(intr_status & DMA_STATUS_RI)) {
210 			u32 value = readl(ioaddr + DMA_INTR_ENA);
211 			/* to schedule NAPI on real RIE event. */
212 			if (likely(value & DMA_INTR_ENA_RIE)) {
213 				x->rx_normal_irq_n++;
214 				ret |= handle_rx;
215 			}
216 		}
217 		if (likely(intr_status & DMA_STATUS_TI)) {
218 			x->tx_normal_irq_n++;
219 			ret |= handle_tx;
220 		}
221 		if (unlikely(intr_status & DMA_STATUS_ERI))
222 			x->rx_early_irq++;
223 	}
224 	/* Optional hardware blocks, interrupts should be disabled */
225 	if (unlikely(intr_status &
226 		     (DMA_STATUS_GPI | DMA_STATUS_GMI | DMA_STATUS_GLI)))
227 		pr_warn("%s: unexpected status %08x\n", __func__, intr_status);
228 
229 	/* Clear the interrupt by writing a logic 1 to the CSR5[15-0] */
230 	writel((intr_status & 0x1ffff), ioaddr + DMA_STATUS);
231 
232 	return ret;
233 }
234 
235 void dwmac_dma_flush_tx_fifo(void __iomem *ioaddr)
236 {
237 	u32 csr6 = readl(ioaddr + DMA_CONTROL);
238 	writel((csr6 | DMA_CONTROL_FTF), ioaddr + DMA_CONTROL);
239 
240 	do {} while ((readl(ioaddr + DMA_CONTROL) & DMA_CONTROL_FTF));
241 }
242 
243 void stmmac_set_mac_addr(void __iomem *ioaddr, u8 addr[6],
244 			 unsigned int high, unsigned int low)
245 {
246 	unsigned long data;
247 
248 	data = (addr[5] << 8) | addr[4];
249 	/* For MAC Addr registers se have to set the Address Enable (AE)
250 	 * bit that has no effect on the High Reg 0 where the bit 31 (MO)
251 	 * is RO.
252 	 */
253 	writel(data | GMAC_HI_REG_AE, ioaddr + high);
254 	data = (addr[3] << 24) | (addr[2] << 16) | (addr[1] << 8) | addr[0];
255 	writel(data, ioaddr + low);
256 }
257 
258 /* Enable disable MAC RX/TX */
259 void stmmac_set_mac(void __iomem *ioaddr, bool enable)
260 {
261 	u32 value = readl(ioaddr + MAC_CTRL_REG);
262 
263 	if (enable)
264 		value |= MAC_RNABLE_RX | MAC_ENABLE_TX;
265 	else
266 		value &= ~(MAC_ENABLE_TX | MAC_RNABLE_RX);
267 
268 	writel(value, ioaddr + MAC_CTRL_REG);
269 }
270 
271 void stmmac_get_mac_addr(void __iomem *ioaddr, unsigned char *addr,
272 			 unsigned int high, unsigned int low)
273 {
274 	unsigned int hi_addr, lo_addr;
275 
276 	/* Read the MAC address from the hardware */
277 	hi_addr = readl(ioaddr + high);
278 	lo_addr = readl(ioaddr + low);
279 
280 	/* Extract the MAC address from the high and low words */
281 	addr[0] = lo_addr & 0xff;
282 	addr[1] = (lo_addr >> 8) & 0xff;
283 	addr[2] = (lo_addr >> 16) & 0xff;
284 	addr[3] = (lo_addr >> 24) & 0xff;
285 	addr[4] = hi_addr & 0xff;
286 	addr[5] = (hi_addr >> 8) & 0xff;
287 }
288 
289