1 /*******************************************************************************
2   This is the driver for the MAC 10/100 on-chip Ethernet controller
3   currently tested on all the ST boards based on STb7109 and stx7200 SoCs.
4 
5   DWC Ether MAC 10/100 Universal version 4.0 has been used for developing
6   this code.
7 
8   This contains the functions to handle the dma.
9 
10   Copyright (C) 2007-2009  STMicroelectronics Ltd
11 
12   This program is free software; you can redistribute it and/or modify it
13   under the terms and conditions of the GNU General Public License,
14   version 2, as published by the Free Software Foundation.
15 
16   This program is distributed in the hope it will be useful, but WITHOUT
17   ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
18   FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
19   more details.
20 
21   The full GNU General Public License is included in this distribution in
22   the file called "COPYING".
23 
24   Author: Giuseppe Cavallaro <peppe.cavallaro@st.com>
25 *******************************************************************************/
26 
27 #include <asm/io.h>
28 #include "dwmac100.h"
29 #include "dwmac_dma.h"
30 
31 static void dwmac100_dma_init(void __iomem *ioaddr,
32 			      struct stmmac_dma_cfg *dma_cfg,
33 			      u32 dma_tx, u32 dma_rx, int atds)
34 {
35 	/* Enable Application Access by writing to DMA CSR0 */
36 	writel(DMA_BUS_MODE_DEFAULT | (dma_cfg->pbl << DMA_BUS_MODE_PBL_SHIFT),
37 	       ioaddr + DMA_BUS_MODE);
38 
39 	/* Mask interrupts by writing to CSR7 */
40 	writel(DMA_INTR_DEFAULT_MASK, ioaddr + DMA_INTR_ENA);
41 
42 	/* RX/TX descriptor base addr lists must be written into
43 	 * DMA CSR3 and CSR4, respectively
44 	 */
45 	writel(dma_tx, ioaddr + DMA_TX_BASE_ADDR);
46 	writel(dma_rx, ioaddr + DMA_RCV_BASE_ADDR);
47 }
48 
49 /* Store and Forward capability is not used at all.
50  *
51  * The transmit threshold can be programmed by setting the TTC bits in the DMA
52  * control register.
53  */
54 static void dwmac100_dma_operation_mode(void __iomem *ioaddr, int txmode,
55 					int rxmode, int rxfifosz)
56 {
57 	u32 csr6 = readl(ioaddr + DMA_CONTROL);
58 
59 	if (txmode <= 32)
60 		csr6 |= DMA_CONTROL_TTC_32;
61 	else if (txmode <= 64)
62 		csr6 |= DMA_CONTROL_TTC_64;
63 	else
64 		csr6 |= DMA_CONTROL_TTC_128;
65 
66 	writel(csr6, ioaddr + DMA_CONTROL);
67 }
68 
69 static void dwmac100_dump_dma_regs(void __iomem *ioaddr, u32 *reg_space)
70 {
71 	int i;
72 
73 	for (i = 0; i < 9; i++)
74 		reg_space[DMA_BUS_MODE / 4 + i] =
75 			readl(ioaddr + DMA_BUS_MODE + i * 4);
76 
77 	reg_space[DMA_CUR_TX_BUF_ADDR / 4] =
78 		readl(ioaddr + DMA_CUR_TX_BUF_ADDR);
79 	reg_space[DMA_CUR_RX_BUF_ADDR / 4] =
80 		readl(ioaddr + DMA_CUR_RX_BUF_ADDR);
81 }
82 
83 /* DMA controller has two counters to track the number of the missed frames. */
84 static void dwmac100_dma_diagnostic_fr(void *data, struct stmmac_extra_stats *x,
85 				       void __iomem *ioaddr)
86 {
87 	struct net_device_stats *stats = (struct net_device_stats *)data;
88 	u32 csr8 = readl(ioaddr + DMA_MISSED_FRAME_CTR);
89 
90 	if (unlikely(csr8)) {
91 		if (csr8 & DMA_MISSED_FRAME_OVE) {
92 			stats->rx_over_errors += 0x800;
93 			x->rx_overflow_cntr += 0x800;
94 		} else {
95 			unsigned int ove_cntr;
96 			ove_cntr = ((csr8 & DMA_MISSED_FRAME_OVE_CNTR) >> 17);
97 			stats->rx_over_errors += ove_cntr;
98 			x->rx_overflow_cntr += ove_cntr;
99 		}
100 
101 		if (csr8 & DMA_MISSED_FRAME_OVE_M) {
102 			stats->rx_missed_errors += 0xffff;
103 			x->rx_missed_cntr += 0xffff;
104 		} else {
105 			unsigned int miss_f = (csr8 & DMA_MISSED_FRAME_M_CNTR);
106 			stats->rx_missed_errors += miss_f;
107 			x->rx_missed_cntr += miss_f;
108 		}
109 	}
110 }
111 
112 const struct stmmac_dma_ops dwmac100_dma_ops = {
113 	.reset = dwmac_dma_reset,
114 	.init = dwmac100_dma_init,
115 	.dump_regs = dwmac100_dump_dma_regs,
116 	.dma_mode = dwmac100_dma_operation_mode,
117 	.dma_diagnostic_fr = dwmac100_dma_diagnostic_fr,
118 	.enable_dma_transmission = dwmac_enable_dma_transmission,
119 	.enable_dma_irq = dwmac_enable_dma_irq,
120 	.disable_dma_irq = dwmac_disable_dma_irq,
121 	.start_tx = dwmac_dma_start_tx,
122 	.stop_tx = dwmac_dma_stop_tx,
123 	.start_rx = dwmac_dma_start_rx,
124 	.stop_rx = dwmac_dma_stop_rx,
125 	.dma_interrupt = dwmac_dma_interrupt,
126 };
127