1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * the ISA Virtual Support Module of AMD CS5536
4  *
5  * Copyright (C) 2007 Lemote, Inc.
6  * Author : jlliu, liujl@lemote.com
7  *
8  * Copyright (C) 2009 Lemote, Inc.
9  * Author: Wu Zhangjin, wuzhangjin@gmail.com
10  */
11 
12 #include <linux/pci.h>
13 #include <cs5536/cs5536.h>
14 #include <cs5536/cs5536_pci.h>
15 
16 /* common variables for PCI_ISA_READ/WRITE_BAR */
17 static const u32 divil_msr_reg[6] = {
18 	DIVIL_MSR_REG(DIVIL_LBAR_SMB), DIVIL_MSR_REG(DIVIL_LBAR_GPIO),
19 	DIVIL_MSR_REG(DIVIL_LBAR_MFGPT), DIVIL_MSR_REG(DIVIL_LBAR_IRQ),
20 	DIVIL_MSR_REG(DIVIL_LBAR_PMS), DIVIL_MSR_REG(DIVIL_LBAR_ACPI),
21 };
22 
23 static const u32 soft_bar_flag[6] = {
24 	SOFT_BAR_SMB_FLAG, SOFT_BAR_GPIO_FLAG, SOFT_BAR_MFGPT_FLAG,
25 	SOFT_BAR_IRQ_FLAG, SOFT_BAR_PMS_FLAG, SOFT_BAR_ACPI_FLAG,
26 };
27 
28 static const u32 sb_msr_reg[6] = {
29 	SB_MSR_REG(SB_R0), SB_MSR_REG(SB_R1), SB_MSR_REG(SB_R2),
30 	SB_MSR_REG(SB_R3), SB_MSR_REG(SB_R4), SB_MSR_REG(SB_R5),
31 };
32 
33 static const u32 bar_space_range[6] = {
34 	CS5536_SMB_RANGE, CS5536_GPIO_RANGE, CS5536_MFGPT_RANGE,
35 	CS5536_IRQ_RANGE, CS5536_PMS_RANGE, CS5536_ACPI_RANGE,
36 };
37 
38 static const int bar_space_len[6] = {
39 	CS5536_SMB_LENGTH, CS5536_GPIO_LENGTH, CS5536_MFGPT_LENGTH,
40 	CS5536_IRQ_LENGTH, CS5536_PMS_LENGTH, CS5536_ACPI_LENGTH,
41 };
42 
43 /*
44  * enable the divil module bar space.
45  *
46  * For all the DIVIL module LBAR, you should control the DIVIL LBAR reg
47  * and the RCONFx(0~5) reg to use the modules.
48  */
49 static void divil_lbar_enable(void)
50 {
51 	u32 hi, lo;
52 	int offset;
53 
54 	/*
55 	 * The DIVIL IRQ is not used yet. and make the RCONF0 reserved.
56 	 */
57 
58 	for (offset = DIVIL_LBAR_SMB; offset <= DIVIL_LBAR_PMS; offset++) {
59 		_rdmsr(DIVIL_MSR_REG(offset), &hi, &lo);
60 		hi |= 0x01;
61 		_wrmsr(DIVIL_MSR_REG(offset), hi, lo);
62 	}
63 }
64 
65 /*
66  * disable the divil module bar space.
67  */
68 static void divil_lbar_disable(void)
69 {
70 	u32 hi, lo;
71 	int offset;
72 
73 	for (offset = DIVIL_LBAR_SMB; offset <= DIVIL_LBAR_PMS; offset++) {
74 		_rdmsr(DIVIL_MSR_REG(offset), &hi, &lo);
75 		hi &= ~0x01;
76 		_wrmsr(DIVIL_MSR_REG(offset), hi, lo);
77 	}
78 }
79 
80 /*
81  * BAR write: write value to the n BAR
82  */
83 
84 void pci_isa_write_bar(int n, u32 value)
85 {
86 	u32 hi = 0, lo = value;
87 
88 	if (value == PCI_BAR_RANGE_MASK) {
89 		_rdmsr(GLCP_MSR_REG(GLCP_SOFT_COM), &hi, &lo);
90 		lo |= soft_bar_flag[n];
91 		_wrmsr(GLCP_MSR_REG(GLCP_SOFT_COM), hi, lo);
92 	} else if (value & 0x01) {
93 		/* NATIVE reg */
94 		hi = 0x0000f001;
95 		lo &= bar_space_range[n];
96 		_wrmsr(divil_msr_reg[n], hi, lo);
97 
98 		/* RCONFx is 4bytes in units for I/O space */
99 		hi = ((value & 0x000ffffc) << 12) |
100 		    ((bar_space_len[n] - 4) << 12) | 0x01;
101 		lo = ((value & 0x000ffffc) << 12) | 0x01;
102 		_wrmsr(sb_msr_reg[n], hi, lo);
103 	}
104 }
105 
106 /*
107  * BAR read: read the n BAR
108  */
109 
110 u32 pci_isa_read_bar(int n)
111 {
112 	u32 conf_data = 0;
113 	u32 hi, lo;
114 
115 	_rdmsr(GLCP_MSR_REG(GLCP_SOFT_COM), &hi, &lo);
116 	if (lo & soft_bar_flag[n]) {
117 		conf_data = bar_space_range[n] | PCI_BASE_ADDRESS_SPACE_IO;
118 		lo &= ~soft_bar_flag[n];
119 		_wrmsr(GLCP_MSR_REG(GLCP_SOFT_COM), hi, lo);
120 	} else {
121 		_rdmsr(divil_msr_reg[n], &hi, &lo);
122 		conf_data = lo & bar_space_range[n];
123 		conf_data |= 0x01;
124 		conf_data &= ~0x02;
125 	}
126 	return conf_data;
127 }
128 
129 /*
130  * isa_write: ISA write transfer
131  *
132  * We assume that this is not a bus master transfer.
133  */
134 void pci_isa_write_reg(int reg, u32 value)
135 {
136 	u32 hi = 0, lo = value;
137 	u32 temp;
138 
139 	switch (reg) {
140 	case PCI_COMMAND:
141 		if (value & PCI_COMMAND_IO)
142 			divil_lbar_enable();
143 		else
144 			divil_lbar_disable();
145 		break;
146 	case PCI_STATUS:
147 		_rdmsr(SB_MSR_REG(SB_ERROR), &hi, &lo);
148 		temp = lo & 0x0000ffff;
149 		if ((value & PCI_STATUS_SIG_TARGET_ABORT) &&
150 		    (lo & SB_TAS_ERR_EN))
151 			temp |= SB_TAS_ERR_FLAG;
152 
153 		if ((value & PCI_STATUS_REC_TARGET_ABORT) &&
154 		    (lo & SB_TAR_ERR_EN))
155 			temp |= SB_TAR_ERR_FLAG;
156 
157 		if ((value & PCI_STATUS_REC_MASTER_ABORT)
158 		    && (lo & SB_MAR_ERR_EN))
159 			temp |= SB_MAR_ERR_FLAG;
160 
161 		if ((value & PCI_STATUS_DETECTED_PARITY)
162 		    && (lo & SB_PARE_ERR_EN))
163 			temp |= SB_PARE_ERR_FLAG;
164 
165 		lo = temp;
166 		_wrmsr(SB_MSR_REG(SB_ERROR), hi, lo);
167 		break;
168 	case PCI_CACHE_LINE_SIZE:
169 		value &= 0x0000ff00;
170 		_rdmsr(SB_MSR_REG(SB_CTRL), &hi, &lo);
171 		hi &= 0xffffff00;
172 		hi |= (value >> 8);
173 		_wrmsr(SB_MSR_REG(SB_CTRL), hi, lo);
174 		break;
175 	case PCI_BAR0_REG:
176 		pci_isa_write_bar(0, value);
177 		break;
178 	case PCI_BAR1_REG:
179 		pci_isa_write_bar(1, value);
180 		break;
181 	case PCI_BAR2_REG:
182 		pci_isa_write_bar(2, value);
183 		break;
184 	case PCI_BAR3_REG:
185 		pci_isa_write_bar(3, value);
186 		break;
187 	case PCI_BAR4_REG:
188 		pci_isa_write_bar(4, value);
189 		break;
190 	case PCI_BAR5_REG:
191 		pci_isa_write_bar(5, value);
192 		break;
193 	case PCI_UART1_INT_REG:
194 		_rdmsr(DIVIL_MSR_REG(PIC_YSEL_HIGH), &hi, &lo);
195 		/* disable uart1 interrupt in PIC */
196 		lo &= ~(0xf << 24);
197 		if (value)	/* enable uart1 interrupt in PIC */
198 			lo |= (CS5536_UART1_INTR << 24);
199 		_wrmsr(DIVIL_MSR_REG(PIC_YSEL_HIGH), hi, lo);
200 		break;
201 	case PCI_UART2_INT_REG:
202 		_rdmsr(DIVIL_MSR_REG(PIC_YSEL_HIGH), &hi, &lo);
203 		/* disable uart2 interrupt in PIC */
204 		lo &= ~(0xf << 28);
205 		if (value)	/* enable uart2 interrupt in PIC */
206 			lo |= (CS5536_UART2_INTR << 28);
207 		_wrmsr(DIVIL_MSR_REG(PIC_YSEL_HIGH), hi, lo);
208 		break;
209 	case PCI_ISA_FIXUP_REG:
210 		if (value) {
211 			/* enable the TARGET ABORT/MASTER ABORT etc. */
212 			_rdmsr(SB_MSR_REG(SB_ERROR), &hi, &lo);
213 			lo |= 0x00000063;
214 			_wrmsr(SB_MSR_REG(SB_ERROR), hi, lo);
215 		}
216 		break;
217 	default:
218 		/* ALL OTHER PCI CONFIG SPACE HEADER IS NOT IMPLEMENTED. */
219 		break;
220 	}
221 }
222 
223 /*
224  * isa_read: ISA read transfers
225  *
226  * We assume that this is not a bus master transfer.
227  */
228 u32 pci_isa_read_reg(int reg)
229 {
230 	u32 conf_data = 0;
231 	u32 hi, lo;
232 
233 	switch (reg) {
234 	case PCI_VENDOR_ID:
235 		conf_data =
236 		    CFG_PCI_VENDOR_ID(CS5536_ISA_DEVICE_ID, CS5536_VENDOR_ID);
237 		break;
238 	case PCI_COMMAND:
239 		/* we just check the first LBAR for the IO enable bit, */
240 		/* maybe we should changed later. */
241 		_rdmsr(DIVIL_MSR_REG(DIVIL_LBAR_SMB), &hi, &lo);
242 		if (hi & 0x01)
243 			conf_data |= PCI_COMMAND_IO;
244 		break;
245 	case PCI_STATUS:
246 		conf_data |= PCI_STATUS_66MHZ;
247 		conf_data |= PCI_STATUS_DEVSEL_MEDIUM;
248 		conf_data |= PCI_STATUS_FAST_BACK;
249 
250 		_rdmsr(SB_MSR_REG(SB_ERROR), &hi, &lo);
251 		if (lo & SB_TAS_ERR_FLAG)
252 			conf_data |= PCI_STATUS_SIG_TARGET_ABORT;
253 		if (lo & SB_TAR_ERR_FLAG)
254 			conf_data |= PCI_STATUS_REC_TARGET_ABORT;
255 		if (lo & SB_MAR_ERR_FLAG)
256 			conf_data |= PCI_STATUS_REC_MASTER_ABORT;
257 		if (lo & SB_PARE_ERR_FLAG)
258 			conf_data |= PCI_STATUS_DETECTED_PARITY;
259 		break;
260 	case PCI_CLASS_REVISION:
261 		_rdmsr(GLCP_MSR_REG(GLCP_CHIP_REV_ID), &hi, &lo);
262 		conf_data = lo & 0x000000ff;
263 		conf_data |= (CS5536_ISA_CLASS_CODE << 8);
264 		break;
265 	case PCI_CACHE_LINE_SIZE:
266 		_rdmsr(SB_MSR_REG(SB_CTRL), &hi, &lo);
267 		hi &= 0x000000f8;
268 		conf_data = CFG_PCI_CACHE_LINE_SIZE(PCI_BRIDGE_HEADER_TYPE, hi);
269 		break;
270 		/*
271 		 * we only use the LBAR of DIVIL, no RCONF used.
272 		 * all of them are IO space.
273 		 */
274 	case PCI_BAR0_REG:
275 		return pci_isa_read_bar(0);
276 		break;
277 	case PCI_BAR1_REG:
278 		return pci_isa_read_bar(1);
279 		break;
280 	case PCI_BAR2_REG:
281 		return pci_isa_read_bar(2);
282 		break;
283 	case PCI_BAR3_REG:
284 		break;
285 	case PCI_BAR4_REG:
286 		return pci_isa_read_bar(4);
287 		break;
288 	case PCI_BAR5_REG:
289 		return pci_isa_read_bar(5);
290 		break;
291 	case PCI_CARDBUS_CIS:
292 		conf_data = PCI_CARDBUS_CIS_POINTER;
293 		break;
294 	case PCI_SUBSYSTEM_VENDOR_ID:
295 		conf_data =
296 		    CFG_PCI_VENDOR_ID(CS5536_ISA_SUB_ID, CS5536_SUB_VENDOR_ID);
297 		break;
298 	case PCI_ROM_ADDRESS:
299 		conf_data = PCI_EXPANSION_ROM_BAR;
300 		break;
301 	case PCI_CAPABILITY_LIST:
302 		conf_data = PCI_CAPLIST_POINTER;
303 		break;
304 	case PCI_INTERRUPT_LINE:
305 		/* no interrupt used here */
306 		conf_data = CFG_PCI_INTERRUPT_LINE(0x00, 0x00);
307 		break;
308 	default:
309 		break;
310 	}
311 
312 	return conf_data;
313 }
314 
315 /*
316  * The mfgpt timer interrupt is running early, so we must keep the south bridge
317  * mmio always enabled. Otherwise we may race with the PCI configuration which
318  * may temporarily disable it. When that happens and the timer interrupt fires,
319  * we are not able to clear it and the system will hang.
320  */
321 static void cs5536_isa_mmio_always_on(struct pci_dev *dev)
322 {
323 	dev->mmio_always_on = 1;
324 }
325 DECLARE_PCI_FIXUP_CLASS_EARLY(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CS5536_ISA,
326 	PCI_CLASS_BRIDGE_ISA, 8, cs5536_isa_mmio_always_on);
327