1// SPDX-License-Identifier: GPL-2.0-only
2/* Altera TSE SGDMA and MSGDMA Linux driver
3 * Copyright (C) 2014 Altera Corporation. All rights reserved
4 */
5
6#include <linux/netdevice.h>
7#include "altera_utils.h"
8#include "altera_tse.h"
9#include "altera_msgdmahw.h"
10#include "altera_msgdma.h"
11
12/* No initialization work to do for MSGDMA */
13int msgdma_initialize(struct altera_tse_private *priv)
14{
15 return 0;
16}
17
18void msgdma_uninitialize(struct altera_tse_private *priv)
19{
20}
21
22void msgdma_start_rxdma(struct altera_tse_private *priv)
23{
24}
25
26void msgdma_reset(struct altera_tse_private *priv)
27{
28 int counter;
29
30 /* Reset Rx mSGDMA */
31 csrwr32(MSGDMA_CSR_STAT_MASK, mac: priv->rx_dma_csr,
32 msgdma_csroffs(status));
33 csrwr32(MSGDMA_CSR_CTL_RESET, mac: priv->rx_dma_csr,
34 msgdma_csroffs(control));
35
36 counter = 0;
37 while (counter++ < ALTERA_TSE_SW_RESET_WATCHDOG_CNTR) {
38 if (tse_bit_is_clear(ioaddr: priv->rx_dma_csr, msgdma_csroffs(status),
39 MSGDMA_CSR_STAT_RESETTING))
40 break;
41 udelay(1);
42 }
43
44 if (counter >= ALTERA_TSE_SW_RESET_WATCHDOG_CNTR)
45 netif_warn(priv, drv, priv->dev,
46 "TSE Rx mSGDMA resetting bit never cleared!\n");
47
48 /* clear all status bits */
49 csrwr32(MSGDMA_CSR_STAT_MASK, mac: priv->rx_dma_csr, msgdma_csroffs(status));
50
51 /* Reset Tx mSGDMA */
52 csrwr32(MSGDMA_CSR_STAT_MASK, mac: priv->tx_dma_csr,
53 msgdma_csroffs(status));
54
55 csrwr32(MSGDMA_CSR_CTL_RESET, mac: priv->tx_dma_csr,
56 msgdma_csroffs(control));
57
58 counter = 0;
59 while (counter++ < ALTERA_TSE_SW_RESET_WATCHDOG_CNTR) {
60 if (tse_bit_is_clear(ioaddr: priv->tx_dma_csr, msgdma_csroffs(status),
61 MSGDMA_CSR_STAT_RESETTING))
62 break;
63 udelay(1);
64 }
65
66 if (counter >= ALTERA_TSE_SW_RESET_WATCHDOG_CNTR)
67 netif_warn(priv, drv, priv->dev,
68 "TSE Tx mSGDMA resetting bit never cleared!\n");
69
70 /* clear all status bits */
71 csrwr32(MSGDMA_CSR_STAT_MASK, mac: priv->tx_dma_csr, msgdma_csroffs(status));
72}
73
74void msgdma_disable_rxirq(struct altera_tse_private *priv)
75{
76 tse_clear_bit(ioaddr: priv->rx_dma_csr, msgdma_csroffs(control),
77 MSGDMA_CSR_CTL_GLOBAL_INTR);
78}
79
80void msgdma_enable_rxirq(struct altera_tse_private *priv)
81{
82 tse_set_bit(ioaddr: priv->rx_dma_csr, msgdma_csroffs(control),
83 MSGDMA_CSR_CTL_GLOBAL_INTR);
84}
85
86void msgdma_disable_txirq(struct altera_tse_private *priv)
87{
88 tse_clear_bit(ioaddr: priv->tx_dma_csr, msgdma_csroffs(control),
89 MSGDMA_CSR_CTL_GLOBAL_INTR);
90}
91
92void msgdma_enable_txirq(struct altera_tse_private *priv)
93{
94 tse_set_bit(ioaddr: priv->tx_dma_csr, msgdma_csroffs(control),
95 MSGDMA_CSR_CTL_GLOBAL_INTR);
96}
97
98void msgdma_clear_rxirq(struct altera_tse_private *priv)
99{
100 csrwr32(MSGDMA_CSR_STAT_IRQ, mac: priv->rx_dma_csr, msgdma_csroffs(status));
101}
102
103void msgdma_clear_txirq(struct altera_tse_private *priv)
104{
105 csrwr32(MSGDMA_CSR_STAT_IRQ, mac: priv->tx_dma_csr, msgdma_csroffs(status));
106}
107
108/* return 0 to indicate transmit is pending */
109int msgdma_tx_buffer(struct altera_tse_private *priv, struct tse_buffer *buffer)
110{
111 csrwr32(lower_32_bits(buffer->dma_addr), mac: priv->tx_dma_desc,
112 msgdma_descroffs(read_addr_lo));
113 csrwr32(upper_32_bits(buffer->dma_addr), mac: priv->tx_dma_desc,
114 msgdma_descroffs(read_addr_hi));
115 csrwr32(val: 0, mac: priv->tx_dma_desc, msgdma_descroffs(write_addr_lo));
116 csrwr32(val: 0, mac: priv->tx_dma_desc, msgdma_descroffs(write_addr_hi));
117 csrwr32(val: buffer->len, mac: priv->tx_dma_desc, msgdma_descroffs(len));
118 csrwr32(val: 0, mac: priv->tx_dma_desc, msgdma_descroffs(burst_seq_num));
119 csrwr32(MSGDMA_DESC_TX_STRIDE, mac: priv->tx_dma_desc,
120 msgdma_descroffs(stride));
121 csrwr32(MSGDMA_DESC_CTL_TX_SINGLE, mac: priv->tx_dma_desc,
122 msgdma_descroffs(control));
123 return 0;
124}
125
126u32 msgdma_tx_completions(struct altera_tse_private *priv)
127{
128 u32 ready = 0;
129 u32 inuse;
130 u32 status;
131
132 /* Get number of sent descriptors */
133 inuse = csrrd32(mac: priv->tx_dma_csr, msgdma_csroffs(rw_fill_level))
134 & 0xffff;
135
136 if (inuse) { /* Tx FIFO is not empty */
137 ready = max_t(int,
138 priv->tx_prod - priv->tx_cons - inuse - 1, 0);
139 } else {
140 /* Check for buffered last packet */
141 status = csrrd32(mac: priv->tx_dma_csr, msgdma_csroffs(status));
142 if (status & MSGDMA_CSR_STAT_BUSY)
143 ready = priv->tx_prod - priv->tx_cons - 1;
144 else
145 ready = priv->tx_prod - priv->tx_cons;
146 }
147 return ready;
148}
149
150/* Put buffer to the mSGDMA RX FIFO
151 */
152void msgdma_add_rx_desc(struct altera_tse_private *priv,
153 struct tse_buffer *rxbuffer)
154{
155 u32 len = priv->rx_dma_buf_sz;
156 dma_addr_t dma_addr = rxbuffer->dma_addr;
157 u32 control = (MSGDMA_DESC_CTL_END_ON_EOP
158 | MSGDMA_DESC_CTL_END_ON_LEN
159 | MSGDMA_DESC_CTL_TR_COMP_IRQ
160 | MSGDMA_DESC_CTL_EARLY_IRQ
161 | MSGDMA_DESC_CTL_TR_ERR_IRQ
162 | MSGDMA_DESC_CTL_GO);
163
164 csrwr32(val: 0, mac: priv->rx_dma_desc, msgdma_descroffs(read_addr_lo));
165 csrwr32(val: 0, mac: priv->rx_dma_desc, msgdma_descroffs(read_addr_hi));
166 csrwr32(lower_32_bits(dma_addr), mac: priv->rx_dma_desc,
167 msgdma_descroffs(write_addr_lo));
168 csrwr32(upper_32_bits(dma_addr), mac: priv->rx_dma_desc,
169 msgdma_descroffs(write_addr_hi));
170 csrwr32(val: len, mac: priv->rx_dma_desc, msgdma_descroffs(len));
171 csrwr32(val: 0, mac: priv->rx_dma_desc, msgdma_descroffs(burst_seq_num));
172 csrwr32(val: 0x00010001, mac: priv->rx_dma_desc, msgdma_descroffs(stride));
173 csrwr32(val: control, mac: priv->rx_dma_desc, msgdma_descroffs(control));
174}
175
176/* status is returned on upper 16 bits,
177 * length is returned in lower 16 bits
178 */
179u32 msgdma_rx_status(struct altera_tse_private *priv)
180{
181 u32 rxstatus = 0;
182 u32 pktlength;
183 u32 pktstatus;
184
185 if (csrrd32(mac: priv->rx_dma_csr, msgdma_csroffs(resp_fill_level))
186 & 0xffff) {
187 pktlength = csrrd32(mac: priv->rx_dma_resp,
188 msgdma_respoffs(bytes_transferred));
189 pktstatus = csrrd32(mac: priv->rx_dma_resp,
190 msgdma_respoffs(status));
191 rxstatus = pktstatus;
192 rxstatus = rxstatus << 16;
193 rxstatus |= (pktlength & 0xffff);
194 }
195 return rxstatus;
196}
197

source code of linux/drivers/net/ethernet/altera/altera_msgdma.c