xref: /titanic_52/usr/src/uts/i86pc/io/pcplusmp/apic_regops.c (revision fcf3ce441efd61da9bb2884968af01cb7c1452cc)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #include <sys/cpuvar.h>
27 #include <sys/psm.h>
28 #include <sys/archsystm.h>
29 #include <sys/apic.h>
30 #include <sys/sunddi.h>
31 #include <sys/ddi_impldefs.h>
32 #include <sys/mach_intr.h>
33 #include <sys/sysmacros.h>
34 #include <sys/trap.h>
35 #include <sys/x86_archext.h>
36 #include <sys/privregs.h>
37 #include <sys/psm_common.h>
38 
39 /* Function prototypes of local apic and x2apic */
40 static uint64_t local_apic_read(uint32_t reg);
41 static void local_apic_write(uint32_t reg, uint64_t value);
42 static int get_local_apic_pri(void);
43 static void local_apic_write_task_reg(uint64_t value);
44 static void local_apic_write_int_cmd(uint32_t cpu_id, uint32_t cmd1);
45 static uint64_t local_x2apic_read(uint32_t msr);
46 static void local_x2apic_write(uint32_t msr, uint64_t value);
47 static int get_local_x2apic_pri(void);
48 static void local_x2apic_write_task_reg(uint64_t value);
49 static void local_x2apic_write_int_cmd(uint32_t cpu_id, uint32_t cmd1);
50 
51 /*
52  * According to the x2APIC specification:
53  *
54  *   xAPIC global enable    x2APIC enable         Description
55  *   (IA32_APIC_BASE[11])   (IA32_APIC_BASE[10])
56  * -----------------------------------------------------------
57  *      0 			0 	APIC is disabled
58  * 	0			1	Invalid
59  *	1			0	APIC is enabled in xAPIC mode
60  *	1			1	APIC is enabled in x2APIC mode
61  * -----------------------------------------------------------
62  */
63 int	x2apic_enable = 1;
64 int 	apic_mode = LOCAL_APIC;		/* Default mode is Local APIC */
65 
66 /* Uses MMIO (Memory Mapped IO) */
67 static apic_reg_ops_t local_apic_regs_ops = {
68 	local_apic_read,
69 	local_apic_write,
70 	get_local_apic_pri,
71 	local_apic_write_task_reg,
72 	local_apic_write_int_cmd,
73 	apic_send_EOI,
74 };
75 
76 /* x2APIC : Uses RDMSR/WRMSR instructions to access APIC registers */
77 static apic_reg_ops_t x2apic_regs_ops = {
78 	local_x2apic_read,
79 	local_x2apic_write,
80 	get_local_x2apic_pri,
81 	local_x2apic_write_task_reg,
82 	local_x2apic_write_int_cmd,
83 	apic_send_EOI,
84 };
85 
86 
87 /* The default ops is local APIC (Memory Mapped IO) */
88 apic_reg_ops_t *apic_reg_ops = &local_apic_regs_ops;
89 
90 /*
91  * APIC register ops related data sturctures and functions.
92  */
93 int	apic_direct_EOI = 0;			/* Directed EOI Support */
94 
95 void apic_send_EOI();
96 void apic_send_directed_EOI(uint32_t irq);
97 
98 #define	X2APIC_CPUID_BIT	21
99 #define	X2APIC_ENABLE_BIT	10
100 
101 /*
102  * Local APIC Implementation
103  */
104 static uint64_t
105 local_apic_read(uint32_t reg)
106 {
107 	return ((uint32_t)apicadr[reg]);
108 }
109 
110 static void
111 local_apic_write(uint32_t reg, uint64_t value)
112 {
113 	apicadr[reg] = (uint32_t)value;
114 }
115 
116 static int
117 get_local_apic_pri(void)
118 {
119 #if defined(__amd64)
120 	return ((int)getcr8());
121 #else
122 	return (apicadr[APIC_TASK_REG]);
123 #endif
124 }
125 
126 static void
127 local_apic_write_task_reg(uint64_t value)
128 {
129 #if defined(__amd64)
130 	setcr8((ulong_t)(value >> APIC_IPL_SHIFT));
131 #else
132 	apicadr[APIC_TASK_REG] = (uint32_t)value;
133 #endif
134 }
135 
136 static void
137 local_apic_write_int_cmd(uint32_t cpu_id, uint32_t cmd1)
138 {
139 	apicadr[APIC_INT_CMD2] = cpu_id << APIC_ICR_ID_BIT_OFFSET;
140 	apicadr[APIC_INT_CMD1] = cmd1;
141 }
142 
143 /*
144  * x2APIC Implementation.
145  */
146 static uint64_t
147 local_x2apic_read(uint32_t msr)
148 {
149 	uint64_t i;
150 
151 	i = (uint64_t)(rdmsr(REG_X2APIC_BASE_MSR + (msr >> 2)) & 0xffffffff);
152 	return (i);
153 }
154 
155 static void
156 local_x2apic_write(uint32_t msr, uint64_t value)
157 {
158 	uint64_t tmp;
159 
160 	if (msr != APIC_EOI_REG) {
161 		tmp = rdmsr(REG_X2APIC_BASE_MSR + (msr >> 2));
162 		tmp = (tmp & 0xffffffff00000000) | value;
163 	} else {
164 		tmp = 0;
165 	}
166 
167 	wrmsr((REG_X2APIC_BASE_MSR + (msr >> 2)), tmp);
168 }
169 
170 static int
171 get_local_x2apic_pri(void)
172 {
173 	return (rdmsr(REG_X2APIC_BASE_MSR + (APIC_TASK_REG >> 2)));
174 }
175 
176 static void
177 local_x2apic_write_task_reg(uint64_t value)
178 {
179 	X2APIC_WRITE(APIC_TASK_REG, value);
180 }
181 
182 static void
183 local_x2apic_write_int_cmd(uint32_t cpu_id, uint32_t cmd1)
184 {
185 	wrmsr((REG_X2APIC_BASE_MSR + (APIC_INT_CMD1 >> 2)),
186 	    (((uint64_t)cpu_id << 32) | cmd1));
187 }
188 
189 /*ARGSUSED*/
190 void
191 apic_send_EOI(uint32_t irq)
192 {
193 	apic_reg_ops->apic_write(APIC_EOI_REG, 0);
194 }
195 
196 void
197 apic_send_directed_EOI(uint32_t irq)
198 {
199 	uchar_t ioapicindex;
200 	uchar_t vector;
201 	apic_irq_t *apic_irq;
202 	short intr_index;
203 
204 	ASSERT(apic_mode == LOCAL_X2APIC);
205 
206 	apic_irq = apic_irq_table[irq];
207 
208 	while (apic_irq) {
209 		intr_index = apic_irq->airq_mps_intr_index;
210 		if (intr_index == ACPI_INDEX || intr_index >= 0) {
211 			ioapicindex = apic_irq->airq_ioapicindex;
212 			vector = apic_irq->airq_vector;
213 			ioapic_write_eoi(ioapicindex, vector);
214 		}
215 		apic_irq = apic_irq->airq_next;
216 	}
217 }
218 
219 int
220 apic_detect_x2apic(void)
221 {
222 	struct cpuid_regs cp;
223 
224 	if (x2apic_enable == 0)
225 		return (0);
226 
227 	cp.cp_eax = 1;
228 	(void) __cpuid_insn(&cp);
229 
230 	return ((cp.cp_ecx & (0x1 << X2APIC_CPUID_BIT)) ? 1 : 0);
231 }
232 
233 void
234 apic_enable_x2apic(void)
235 {
236 	uint64_t apic_base_msr;
237 
238 	apic_base_msr = rdmsr(REG_APIC_BASE_MSR);
239 	apic_base_msr = apic_base_msr | (0x1 << X2APIC_ENABLE_BIT);
240 
241 	wrmsr(REG_APIC_BASE_MSR, apic_base_msr);
242 
243 	/* change the mode and ops */
244 	if (apic_mode != LOCAL_X2APIC) {
245 		apic_mode = LOCAL_X2APIC;
246 		apic_reg_ops = &x2apic_regs_ops;
247 		x2apic_update_psm();
248 	}
249 }
250 
251 /*
252  * Generates an interprocessor interrupt to another CPU when x2APIC mode is
253  * enabled.
254  */
255 void
256 x2apic_send_ipi(int cpun, int ipl)
257 {
258 	int vector;
259 	ulong_t flag;
260 
261 	ASSERT(apic_mode == LOCAL_X2APIC);
262 
263 	/*
264 	 * With X2APIC, Intel relaxed the semantics of the
265 	 * WRMSR instruction such that references to the X2APIC
266 	 * MSR registers are no longer serializing instructions.
267 	 * The code that initiates IPIs assumes that some sort
268 	 * of memory serialization occurs. The old APIC code
269 	 * did a write to uncachable memory mapped registers.
270 	 * Any reference to uncached memory is a serializing
271 	 * operation. To mimic those semantics here, we do an
272 	 * atomic operation, which translates to a LOCK OR instruction,
273 	 * which is serializing.
274 	 */
275 	atomic_or_ulong(&flag, 1);
276 
277 	vector = apic_resv_vector[ipl];
278 
279 	flag = intr_clear();
280 
281 	/*
282 	 * According to x2APIC specification in section '2.3.5.1' of
283 	 * Interrupt Command Register Semantics, the semantics of
284 	 * programming Interrupt Command Register to dispatch an interrupt
285 	 * is simplified. A single MSR write to the 64-bit ICR is required
286 	 * for dispatching an interrupt. Specifically with the 64-bit MSR
287 	 * interface to ICR, system software is not required to check the
288 	 * status of the delivery status bit prior to writing to the ICR
289 	 * to send an IPI. With the removal of the Delivery Status bit,
290 	 * system software no longer has a reason to read the ICR. It remains
291 	 * readable only to aid in debugging.
292 	 */
293 #ifdef	DEBUG
294 	APIC_AV_PENDING_SET();
295 #endif	/* DEBUG */
296 
297 	if ((cpun == psm_get_cpu_id()))
298 		apic_reg_ops->apic_write(X2APIC_SELF_IPI, vector);
299 	else
300 		apic_reg_ops->apic_write_int_cmd(
301 		    apic_cpus[cpun].aci_local_id, vector);
302 
303 	intr_restore(flag);
304 }
305 
306 
307 void
308 apic_change_eoi()
309 {
310 	apic_reg_ops->apic_send_eoi = apic_send_directed_EOI;
311 }
312