xref: /openbmc/linux/drivers/net/ethernet/amd/7990.h (revision f21e49be)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * 7990.h -- LANCE ethernet IC generic routines.
4  * This is an attempt to separate out the bits of various ethernet
5  * drivers that are common because they all use the AMD 7990 LANCE
6  * (Local Area Network Controller for Ethernet) chip.
7  *
8  * Copyright (C) 05/1998 Peter Maydell <pmaydell@chiark.greenend.org.uk>
9  *
10  * Most of this stuff was obtained by looking at other LANCE drivers,
11  * in particular a2065.[ch]. The AMD C-LANCE datasheet was also helpful.
12  */
13 
14 #ifndef _7990_H
15 #define _7990_H
16 
17 /* The lance only has two register locations. We communicate mostly via memory. */
18 #define LANCE_RDP	0	/* Register Data Port */
19 #define LANCE_RAP	2	/* Register Address Port */
20 
21 /* Transmit/receive ring definitions.
22  * We allow the specific drivers to override these defaults if they want to.
23  * NB: according to lance.c, increasing the number of buffers is a waste
24  * of space and reduces the chance that an upper layer will be able to
25  * reorder queued Tx packets based on priority. [Clearly there is a minimum
26  * limit too: too small and we drop rx packets and can't tx at full speed.]
27  * 4+4 seems to be the usual setting; the atarilance driver uses 3 and 5.
28  */
29 
30 /* Blast! This won't work. The problem is that we can't specify a default
31  * setting because that would cause the lance_init_block struct to be
32  * too long (and overflow the RAM on shared-memory cards like the HP LANCE.
33  */
34 #ifndef LANCE_LOG_TX_BUFFERS
35 #define LANCE_LOG_TX_BUFFERS 1
36 #define LANCE_LOG_RX_BUFFERS 3
37 #endif
38 
39 #define TX_RING_SIZE		(1 << LANCE_LOG_TX_BUFFERS)
40 #define RX_RING_SIZE		(1 << LANCE_LOG_RX_BUFFERS)
41 #define TX_RING_MOD_MASK	(TX_RING_SIZE - 1)
42 #define RX_RING_MOD_MASK	(RX_RING_SIZE - 1)
43 #define TX_RING_LEN_BITS	((LANCE_LOG_TX_BUFFERS) << 29)
44 #define RX_RING_LEN_BITS	((LANCE_LOG_RX_BUFFERS) << 29)
45 #define PKT_BUFF_SIZE		(1544)
46 #define RX_BUFF_SIZE		PKT_BUFF_SIZE
47 #define TX_BUFF_SIZE		PKT_BUFF_SIZE
48 
49 /* Each receive buffer is described by a receive message descriptor (RMD) */
50 struct lance_rx_desc {
51 	volatile unsigned short rmd0;	    /* low address of packet */
52 	volatile unsigned char  rmd1_bits;  /* descriptor bits */
53 	volatile unsigned char  rmd1_hadr;  /* high address of packet */
54 	volatile short    length;	    /* This length is 2s complement (negative)!
55 					     * Buffer length */
56 	volatile unsigned short mblength;   /* Actual number of bytes received */
57 };
58 
59 /* Ditto for TMD: */
60 struct lance_tx_desc {
61 	volatile unsigned short tmd0;	    /* low address of packet */
62 	volatile unsigned char  tmd1_bits;  /* descriptor bits */
63 	volatile unsigned char  tmd1_hadr;  /* high address of packet */
64 	volatile short    length;	    /* Length is 2s complement (negative)! */
65 	volatile unsigned short misc;
66 };
67 
68 /* There are three memory structures accessed by the LANCE:
69  * the initialization block, the receive and transmit descriptor rings,
70  * and the data buffers themselves. In fact we might as well put the
71  * init block,the Tx and Rx rings and the buffers together in memory:
72  */
73 struct lance_init_block {
74 	volatile unsigned short mode;		/* Pre-set mode (reg. 15) */
75 	volatile unsigned char phys_addr[6];	/* Physical ethernet address */
76 	volatile unsigned filter[2];		/* Multicast filter (64 bits) */
77 
78 	/* Receive and transmit ring base, along with extra bits. */
79 	volatile unsigned short rx_ptr;		/* receive descriptor addr */
80 	volatile unsigned short rx_len;		/* receive len and high addr */
81 	volatile unsigned short tx_ptr;		/* transmit descriptor addr */
82 	volatile unsigned short tx_len;		/* transmit len and high addr */
83 
84 	/* The Tx and Rx ring entries must be aligned on 8-byte boundaries.
85 	 * This will be true if this whole struct is 8-byte aligned.
86 	 */
87 	volatile struct lance_tx_desc btx_ring[TX_RING_SIZE];
88 	volatile struct lance_rx_desc brx_ring[RX_RING_SIZE];
89 
90 	volatile char tx_buf[TX_RING_SIZE][TX_BUFF_SIZE];
91 	volatile char rx_buf[RX_RING_SIZE][RX_BUFF_SIZE];
92 	/* we use this just to make the struct big enough that we can move its startaddr
93 	 * in order to force alignment to an eight byte boundary.
94 	 */
95 };
96 
97 /* This is where we keep all the stuff the driver needs to know about.
98  * I'm definitely unhappy about the mechanism for allowing specific
99  * drivers to add things...
100  */
101 struct lance_private {
102 	const char *name;
103 	unsigned long base;
104 	volatile struct lance_init_block *init_block; /* CPU address of RAM */
105 	volatile struct lance_init_block *lance_init_block; /* LANCE address of RAM */
106 
107 	int rx_new, tx_new;
108 	int rx_old, tx_old;
109 
110 	int lance_log_rx_bufs, lance_log_tx_bufs;
111 	int rx_ring_mod_mask, tx_ring_mod_mask;
112 
113 	int tpe;			/* TPE is selected */
114 	int auto_select;		/* cable-selection is by carrier */
115 	unsigned short busmaster_regval;
116 
117 	unsigned int irq;		/* IRQ to register */
118 
119 	/* This is because the HP LANCE is disgusting and you have to check
120 	 * a DIO-specific register every time you read/write the LANCE regs :-<
121 	 * [could we get away with making these some sort of macro?]
122 	 */
123 	void (*writerap)(void *, unsigned short);
124 	void (*writerdp)(void *, unsigned short);
125 	unsigned short (*readrdp)(void *);
126 	spinlock_t devlock;
127 	char tx_full;
128 };
129 
130 /*
131  *		Am7990 Control and Status Registers
132  */
133 #define LE_CSR0		0x0000	/* LANCE Controller Status */
134 #define LE_CSR1		0x0001	/* IADR[15:0] (bit0==0 ie word aligned) */
135 #define LE_CSR2		0x0002	/* IADR[23:16] (high bits reserved) */
136 #define LE_CSR3		0x0003	/* Misc */
137 
138 /*
139  *		Bit definitions for CSR0 (LANCE Controller Status)
140  */
141 #define LE_C0_ERR	0x8000	/* Error = BABL | CERR | MISS | MERR */
142 #define LE_C0_BABL	0x4000	/* Babble: Transmitted too many bits */
143 #define LE_C0_CERR	0x2000	/* No Heartbeat (10BASE-T) */
144 #define LE_C0_MISS	0x1000	/* Missed Frame (no rx buffer to put it in) */
145 #define LE_C0_MERR	0x0800	/* Memory Error */
146 #define LE_C0_RINT	0x0400	/* Receive Interrupt */
147 #define LE_C0_TINT	0x0200	/* Transmit Interrupt */
148 #define LE_C0_IDON	0x0100	/* Initialization Done */
149 #define LE_C0_INTR	0x0080	/* Interrupt Flag
150 				   = BABL | MISS | MERR | RINT | TINT | IDON */
151 #define LE_C0_INEA	0x0040	/* Interrupt Enable */
152 #define LE_C0_RXON	0x0020	/* Receive On */
153 #define LE_C0_TXON	0x0010	/* Transmit On */
154 #define LE_C0_TDMD	0x0008	/* Transmit Demand */
155 #define LE_C0_STOP	0x0004	/* Stop */
156 #define LE_C0_STRT	0x0002	/* Start */
157 #define LE_C0_INIT	0x0001	/* Initialize */
158 
159 
160 /*
161  *		Bit definitions for CSR3
162  */
163 #define LE_C3_BSWP	0x0004	/* Byte Swap (on for big endian byte order) */
164 #define LE_C3_ACON	0x0002	/* ALE Control (on for active low ALE) */
165 #define LE_C3_BCON	0x0001	/* Byte Control */
166 
167 
168 /*
169  *		Mode Flags
170  */
171 #define LE_MO_PROM	0x8000	/* Promiscuous Mode */
172 /* these next ones 0x4000 -- 0x0080 are not available on the LANCE 7990,
173  * but they are in NetBSD's am7990.h, presumably for backwards-compatible chips
174  */
175 #define LE_MO_DRCVBC	0x4000	/* disable receive broadcast */
176 #define LE_MO_DRCVPA	0x2000	/* disable physical address detection */
177 #define LE_MO_DLNKTST	0x1000	/* disable link status */
178 #define LE_MO_DAPC	0x0800	/* disable automatic polarity correction */
179 #define LE_MO_MENDECL	0x0400	/* MENDEC loopback mode */
180 #define LE_MO_LRTTSEL	0x0200	/* lower RX threshold / TX mode selection */
181 #define LE_MO_PSEL1	0x0100	/* port selection bit1 */
182 #define LE_MO_PSEL0	0x0080	/* port selection bit0 */
183 /* and this one is from the C-LANCE data sheet... */
184 #define LE_MO_EMBA	0x0080	/* Enable Modified Backoff Algorithm
185 				   (C-LANCE, not original LANCE) */
186 #define LE_MO_INTL	0x0040	/* Internal Loopback */
187 #define LE_MO_DRTY	0x0020	/* Disable Retry */
188 #define LE_MO_FCOLL	0x0010	/* Force Collision */
189 #define LE_MO_DXMTFCS	0x0008	/* Disable Transmit CRC */
190 #define LE_MO_LOOP	0x0004	/* Loopback Enable */
191 #define LE_MO_DTX	0x0002	/* Disable Transmitter */
192 #define LE_MO_DRX	0x0001	/* Disable Receiver */
193 
194 
195 /*
196  *		Receive Flags
197  */
198 #define LE_R1_OWN	0x80	/* LANCE owns the descriptor */
199 #define LE_R1_ERR	0x40	/* Error */
200 #define LE_R1_FRA	0x20	/* Framing Error */
201 #define LE_R1_OFL	0x10	/* Overflow Error */
202 #define LE_R1_CRC	0x08	/* CRC Error */
203 #define LE_R1_BUF	0x04	/* Buffer Error */
204 #define LE_R1_SOP	0x02	/* Start of Packet */
205 #define LE_R1_EOP	0x01	/* End of Packet */
206 #define LE_R1_POK	0x03	/* Packet is complete: SOP + EOP */
207 
208 
209 /*
210  *		Transmit Flags
211  */
212 #define LE_T1_OWN	0x80	/* LANCE owns the descriptor */
213 #define LE_T1_ERR	0x40	/* Error */
214 #define LE_T1_RES	0x20	/* Reserved, LANCE writes this with a zero */
215 #define LE_T1_EMORE	0x10	/* More than one retry needed */
216 #define LE_T1_EONE	0x08	/* One retry needed */
217 #define LE_T1_EDEF	0x04	/* Deferred */
218 #define LE_T1_SOP	0x02	/* Start of Packet */
219 #define LE_T1_EOP	0x01	/* End of Packet */
220 #define LE_T1_POK	0x03	/* Packet is complete: SOP + EOP */
221 
222 /*
223  *		Error Flags
224  */
225 #define LE_T3_BUF	0x8000	/* Buffer Error */
226 #define LE_T3_UFL	0x4000	/* Underflow Error */
227 #define LE_T3_LCOL	0x1000	/* Late Collision */
228 #define LE_T3_CLOS	0x0800	/* Loss of Carrier */
229 #define LE_T3_RTY	0x0400	/* Retry Error */
230 #define LE_T3_TDR	0x03ff	/* Time Domain Reflectometry */
231 
232 /* Miscellaneous useful macros */
233 
234 #define TX_BUFFS_AVAIL ((lp->tx_old <= lp->tx_new) ? \
235 			lp->tx_old + lp->tx_ring_mod_mask - lp->tx_new : \
236 			lp->tx_old - lp->tx_new - 1)
237 
238 /* The LANCE only uses 24 bit addresses. This does the obvious thing. */
239 #define LANCE_ADDR(x) ((int)(x) & ~0xff000000)
240 
241 /* Now the prototypes we export */
242 int lance_open(struct net_device *dev);
243 int lance_close(struct net_device *dev);
244 netdev_tx_t lance_start_xmit(struct sk_buff *skb, struct net_device *dev);
245 void lance_set_multicast(struct net_device *dev);
246 void lance_tx_timeout(struct net_device *dev, unsigned int txqueue);
247 #ifdef CONFIG_NET_POLL_CONTROLLER
248 void lance_poll(struct net_device *dev);
249 #endif
250 
251 #endif /* ndef _7990_H */
252