xref: /OK3568_Linux_fs/u-boot/arch/x86/cpu/broadwell/iobp.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /*
2*4882a593Smuzhiyun  * Copyright (c) 2016 Google, Inc
3*4882a593Smuzhiyun  *
4*4882a593Smuzhiyun  * Modified from coreboot
5*4882a593Smuzhiyun  *
6*4882a593Smuzhiyun  * SPDX-License-Identifier:	GPL-2.0
7*4882a593Smuzhiyun  */
8*4882a593Smuzhiyun 
9*4882a593Smuzhiyun #include <common.h>
10*4882a593Smuzhiyun #include <errno.h>
11*4882a593Smuzhiyun #include <asm/intel_regs.h>
12*4882a593Smuzhiyun #include <asm/io.h>
13*4882a593Smuzhiyun #include <asm/arch/pch.h>
14*4882a593Smuzhiyun 
15*4882a593Smuzhiyun #define IOBP_RETRY 1000
16*4882a593Smuzhiyun 
17*4882a593Smuzhiyun /* IO Buffer Programming */
18*4882a593Smuzhiyun #define IOBPIRI		0x2330
19*4882a593Smuzhiyun #define IOBPD		0x2334
20*4882a593Smuzhiyun #define IOBPS		0x2338
21*4882a593Smuzhiyun #define  IOBPS_READY	0x0001
22*4882a593Smuzhiyun #define  IOBPS_TX_MASK	0x0006
23*4882a593Smuzhiyun #define  IOBPS_MASK     0xff00
24*4882a593Smuzhiyun #define  IOBPS_READ     0x0600
25*4882a593Smuzhiyun #define  IOBPS_WRITE	0x0700
26*4882a593Smuzhiyun #define IOBPU		0x233a
27*4882a593Smuzhiyun #define  IOBPU_MAGIC	0xf000
28*4882a593Smuzhiyun #define  IOBP_PCICFG_READ	0x0400
29*4882a593Smuzhiyun #define  IOBP_PCICFG_WRITE	0x0500
30*4882a593Smuzhiyun 
iobp_poll(void)31*4882a593Smuzhiyun static inline int iobp_poll(void)
32*4882a593Smuzhiyun {
33*4882a593Smuzhiyun 	unsigned try;
34*4882a593Smuzhiyun 
35*4882a593Smuzhiyun 	for (try = IOBP_RETRY; try > 0; try--) {
36*4882a593Smuzhiyun 		u16 status = readw(RCB_REG(IOBPS));
37*4882a593Smuzhiyun 		if ((status & IOBPS_READY) == 0)
38*4882a593Smuzhiyun 			return 1;
39*4882a593Smuzhiyun 		udelay(10);
40*4882a593Smuzhiyun 	}
41*4882a593Smuzhiyun 
42*4882a593Smuzhiyun 	printf("IOBP: timeout waiting for transaction to complete\n");
43*4882a593Smuzhiyun 	return 0;
44*4882a593Smuzhiyun }
45*4882a593Smuzhiyun 
pch_iobp_trans_start(u32 address,int op)46*4882a593Smuzhiyun int pch_iobp_trans_start(u32 address, int op)
47*4882a593Smuzhiyun {
48*4882a593Smuzhiyun 	if (!iobp_poll())
49*4882a593Smuzhiyun 		return 0;
50*4882a593Smuzhiyun 
51*4882a593Smuzhiyun 	/* Set the address */
52*4882a593Smuzhiyun 	writel(address, RCB_REG(IOBPIRI));
53*4882a593Smuzhiyun 
54*4882a593Smuzhiyun 	/* READ OPCODE */
55*4882a593Smuzhiyun 	clrsetbits_le16(RCB_REG(IOBPS), IOBPS_MASK, op);
56*4882a593Smuzhiyun 
57*4882a593Smuzhiyun 	return 1;
58*4882a593Smuzhiyun }
59*4882a593Smuzhiyun 
pch_iobp_trans_finish(void)60*4882a593Smuzhiyun int pch_iobp_trans_finish(void)
61*4882a593Smuzhiyun {
62*4882a593Smuzhiyun 	u16 status;
63*4882a593Smuzhiyun 
64*4882a593Smuzhiyun 	/* Undocumented magic */
65*4882a593Smuzhiyun 	writew(IOBPU_MAGIC, RCB_REG(IOBPU));
66*4882a593Smuzhiyun 
67*4882a593Smuzhiyun 	/* Set ready bit */
68*4882a593Smuzhiyun 	setbits_le16(RCB_REG(IOBPS), IOBPS_READY);
69*4882a593Smuzhiyun 
70*4882a593Smuzhiyun 	if (!iobp_poll())
71*4882a593Smuzhiyun 		return 1;
72*4882a593Smuzhiyun 
73*4882a593Smuzhiyun 	/* Check for successful transaction */
74*4882a593Smuzhiyun 	status = readw(RCB_REG(IOBPS));
75*4882a593Smuzhiyun 	if (status & IOBPS_TX_MASK)
76*4882a593Smuzhiyun 		return 1;
77*4882a593Smuzhiyun 
78*4882a593Smuzhiyun 	return 0;
79*4882a593Smuzhiyun }
80*4882a593Smuzhiyun 
pch_iobp_read(u32 address)81*4882a593Smuzhiyun u32 pch_iobp_read(u32 address)
82*4882a593Smuzhiyun {
83*4882a593Smuzhiyun 	if (!pch_iobp_trans_start(address, IOBPS_READ))
84*4882a593Smuzhiyun 		return 0;
85*4882a593Smuzhiyun 	if (pch_iobp_trans_finish()) {
86*4882a593Smuzhiyun 		printf("IOBP: read 0x%08x failed\n", address);
87*4882a593Smuzhiyun 		return 0;
88*4882a593Smuzhiyun 	}
89*4882a593Smuzhiyun 
90*4882a593Smuzhiyun 	/* Read IOBP data */
91*4882a593Smuzhiyun 	return readl(RCB_REG(IOBPD));
92*4882a593Smuzhiyun }
93*4882a593Smuzhiyun 
pch_iobp_write(u32 address,u32 data)94*4882a593Smuzhiyun int pch_iobp_write(u32 address, u32 data)
95*4882a593Smuzhiyun {
96*4882a593Smuzhiyun 	if (!pch_iobp_trans_start(address, IOBPS_WRITE))
97*4882a593Smuzhiyun 		return -EIO;
98*4882a593Smuzhiyun 
99*4882a593Smuzhiyun 	writel(data, RCB_REG(IOBPD));
100*4882a593Smuzhiyun 
101*4882a593Smuzhiyun 	if (pch_iobp_trans_finish()) {
102*4882a593Smuzhiyun 		printf("IOBP: write 0x%08x failed\n", address);
103*4882a593Smuzhiyun 		return -EIO;
104*4882a593Smuzhiyun 	}
105*4882a593Smuzhiyun 
106*4882a593Smuzhiyun 	return 0;
107*4882a593Smuzhiyun }
108*4882a593Smuzhiyun 
pch_iobp_update(u32 address,u32 andvalue,u32 orvalue)109*4882a593Smuzhiyun int pch_iobp_update(u32 address, u32 andvalue, u32 orvalue)
110*4882a593Smuzhiyun {
111*4882a593Smuzhiyun 	u32 data = pch_iobp_read(address);
112*4882a593Smuzhiyun 
113*4882a593Smuzhiyun 	/* Update the data */
114*4882a593Smuzhiyun 	data &= andvalue;
115*4882a593Smuzhiyun 	data |= orvalue;
116*4882a593Smuzhiyun 
117*4882a593Smuzhiyun 	return pch_iobp_write(address, data);
118*4882a593Smuzhiyun }
119*4882a593Smuzhiyun 
pch_iobp_exec(u32 addr,u16 op_code,u8 route_id,u32 * data,u8 * resp)120*4882a593Smuzhiyun int pch_iobp_exec(u32 addr, u16 op_code, u8 route_id, u32 *data, u8 *resp)
121*4882a593Smuzhiyun {
122*4882a593Smuzhiyun 	if (!data || !resp)
123*4882a593Smuzhiyun 		return 0;
124*4882a593Smuzhiyun 
125*4882a593Smuzhiyun 	*resp = -1;
126*4882a593Smuzhiyun 	if (!iobp_poll())
127*4882a593Smuzhiyun 		return -EIO;
128*4882a593Smuzhiyun 
129*4882a593Smuzhiyun 	writel(addr, RCB_REG(IOBPIRI));
130*4882a593Smuzhiyun 	clrsetbits_le16(RCB_REG(IOBPS), 0xff00, op_code);
131*4882a593Smuzhiyun 	writew(IOBPU_MAGIC | route_id, RCB_REG(IOBPU));
132*4882a593Smuzhiyun 
133*4882a593Smuzhiyun 	writel(*data, RCB_REG(IOBPD));
134*4882a593Smuzhiyun 	/* Set IOBPS[0] to trigger IOBP transaction*/
135*4882a593Smuzhiyun 	setbits_le16(RCB_REG(IOBPS), 1);
136*4882a593Smuzhiyun 
137*4882a593Smuzhiyun 	if (!iobp_poll())
138*4882a593Smuzhiyun 		return -EIO;
139*4882a593Smuzhiyun 
140*4882a593Smuzhiyun 	*resp = (readw(RCB_REG(IOBPS)) & IOBPS_TX_MASK) >> 1;
141*4882a593Smuzhiyun 	*data = readl(RCB_REG(IOBPD));
142*4882a593Smuzhiyun 
143*4882a593Smuzhiyun 	return 0;
144*4882a593Smuzhiyun }
145