1 /*******************************************************************************
2   This is the driver for the GMAC on-chip Ethernet controller for ST SoCs.
3   DWC Ether MAC 10/100/1000 Universal version 3.41a  has been used for
4   developing this code.
5 
6   This contains the functions to handle the dma.
7 
8   Copyright (C) 2007-2009  STMicroelectronics Ltd
9 
10   This program is free software; you can redistribute it and/or modify it
11   under the terms and conditions of the GNU General Public License,
12   version 2, as published by the Free Software Foundation.
13 
14   This program is distributed in the hope it will be useful, but WITHOUT
15   ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
16   FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
17   more details.
18 
19   You should have received a copy of the GNU General Public License along with
20   this program; if not, write to the Free Software Foundation, Inc.,
21   51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
22 
23   The full GNU General Public License is included in this distribution in
24   the file called "COPYING".
25 
26   Author: Giuseppe Cavallaro <peppe.cavallaro@st.com>
27 *******************************************************************************/
28 
29 #include <asm/io.h>
30 #include "dwmac1000.h"
31 #include "dwmac_dma.h"
32 
33 static int dwmac1000_dma_init(void __iomem *ioaddr, int pbl, u32 dma_tx,
34 			      u32 dma_rx)
35 {
36 	u32 value = readl(ioaddr + DMA_BUS_MODE);
37 	int limit;
38 
39 	/* DMA SW reset */
40 	value |= DMA_BUS_MODE_SFT_RESET;
41 	writel(value, ioaddr + DMA_BUS_MODE);
42 	limit = 10;
43 	while (limit--) {
44 		if (!(readl(ioaddr + DMA_BUS_MODE) & DMA_BUS_MODE_SFT_RESET))
45 			break;
46 		mdelay(10);
47 	}
48 	if (limit < 0)
49 		return -EBUSY;
50 
51 	value = /* DMA_BUS_MODE_FB | */ DMA_BUS_MODE_4PBL |
52 	    ((pbl << DMA_BUS_MODE_PBL_SHIFT) |
53 	     (pbl << DMA_BUS_MODE_RPBL_SHIFT));
54 
55 #ifdef CONFIG_STMMAC_DA
56 	value |= DMA_BUS_MODE_DA;	/* Rx has priority over tx */
57 #endif
58 	writel(value, ioaddr + DMA_BUS_MODE);
59 
60 	/* Mask interrupts by writing to CSR7 */
61 	writel(DMA_INTR_DEFAULT_MASK, ioaddr + DMA_INTR_ENA);
62 
63 	/* The base address of the RX/TX descriptor lists must be written into
64 	 * DMA CSR3 and CSR4, respectively. */
65 	writel(dma_tx, ioaddr + DMA_TX_BASE_ADDR);
66 	writel(dma_rx, ioaddr + DMA_RCV_BASE_ADDR);
67 
68 	return 0;
69 }
70 
71 static void dwmac1000_dma_operation_mode(void __iomem *ioaddr, int txmode,
72 				    int rxmode)
73 {
74 	u32 csr6 = readl(ioaddr + DMA_CONTROL);
75 
76 	if (txmode == SF_DMA_MODE) {
77 		CHIP_DBG(KERN_DEBUG "GMAC: enable TX store and forward mode\n");
78 		/* Transmit COE type 2 cannot be done in cut-through mode. */
79 		csr6 |= DMA_CONTROL_TSF;
80 		/* Operating on second frame increase the performance
81 		 * especially when transmit store-and-forward is used.*/
82 		csr6 |= DMA_CONTROL_OSF;
83 	} else {
84 		CHIP_DBG(KERN_DEBUG "GMAC: disabling TX store and forward mode"
85 			      " (threshold = %d)\n", txmode);
86 		csr6 &= ~DMA_CONTROL_TSF;
87 		csr6 &= DMA_CONTROL_TC_TX_MASK;
88 		/* Set the transmit threshold */
89 		if (txmode <= 32)
90 			csr6 |= DMA_CONTROL_TTC_32;
91 		else if (txmode <= 64)
92 			csr6 |= DMA_CONTROL_TTC_64;
93 		else if (txmode <= 128)
94 			csr6 |= DMA_CONTROL_TTC_128;
95 		else if (txmode <= 192)
96 			csr6 |= DMA_CONTROL_TTC_192;
97 		else
98 			csr6 |= DMA_CONTROL_TTC_256;
99 	}
100 
101 	if (rxmode == SF_DMA_MODE) {
102 		CHIP_DBG(KERN_DEBUG "GMAC: enable RX store and forward mode\n");
103 		csr6 |= DMA_CONTROL_RSF;
104 	} else {
105 		CHIP_DBG(KERN_DEBUG "GMAC: disabling RX store and forward mode"
106 			      " (threshold = %d)\n", rxmode);
107 		csr6 &= ~DMA_CONTROL_RSF;
108 		csr6 &= DMA_CONTROL_TC_RX_MASK;
109 		if (rxmode <= 32)
110 			csr6 |= DMA_CONTROL_RTC_32;
111 		else if (rxmode <= 64)
112 			csr6 |= DMA_CONTROL_RTC_64;
113 		else if (rxmode <= 96)
114 			csr6 |= DMA_CONTROL_RTC_96;
115 		else
116 			csr6 |= DMA_CONTROL_RTC_128;
117 	}
118 
119 	writel(csr6, ioaddr + DMA_CONTROL);
120 }
121 
122 static void dwmac1000_dump_dma_regs(void __iomem *ioaddr)
123 {
124 	int i;
125 	pr_info(" DMA registers\n");
126 	for (i = 0; i < 22; i++) {
127 		if ((i < 9) || (i > 17)) {
128 			int offset = i * 4;
129 			pr_err("\t Reg No. %d (offset 0x%x): 0x%08x\n", i,
130 			       (DMA_BUS_MODE + offset),
131 			       readl(ioaddr + DMA_BUS_MODE + offset));
132 		}
133 	}
134 }
135 
136 static unsigned int dwmac1000_get_hw_feature(void __iomem *ioaddr)
137 {
138 	return readl(ioaddr + DMA_HW_FEATURE);
139 }
140 
141 const struct stmmac_dma_ops dwmac1000_dma_ops = {
142 	.init = dwmac1000_dma_init,
143 	.dump_regs = dwmac1000_dump_dma_regs,
144 	.dma_mode = dwmac1000_dma_operation_mode,
145 	.enable_dma_transmission = dwmac_enable_dma_transmission,
146 	.enable_dma_irq = dwmac_enable_dma_irq,
147 	.disable_dma_irq = dwmac_disable_dma_irq,
148 	.start_tx = dwmac_dma_start_tx,
149 	.stop_tx = dwmac_dma_stop_tx,
150 	.start_rx = dwmac_dma_start_rx,
151 	.stop_rx = dwmac_dma_stop_rx,
152 	.dma_interrupt = dwmac_dma_interrupt,
153 	.get_hw_feature = dwmac1000_get_hw_feature,
154 };
155