xref: /openbmc/linux/arch/mips/mti-malta/malta-int.c (revision 2c684d89)
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Carsten Langgaard, carstenl@mips.com
7  * Copyright (C) 2000, 2001, 2004 MIPS Technologies, Inc.
8  * Copyright (C) 2001 Ralf Baechle
9  * Copyright (C) 2013 Imagination Technologies Ltd.
10  *
11  * Routines for generic manipulation of the interrupts found on the MIPS
12  * Malta board. The interrupt controller is located in the South Bridge
13  * a PIIX4 device with two internal 82C95 interrupt controllers.
14  */
15 #include <linux/init.h>
16 #include <linux/irq.h>
17 #include <linux/sched.h>
18 #include <linux/smp.h>
19 #include <linux/interrupt.h>
20 #include <linux/io.h>
21 #include <linux/irqchip/mips-gic.h>
22 #include <linux/kernel_stat.h>
23 #include <linux/kernel.h>
24 #include <linux/random.h>
25 
26 #include <asm/traps.h>
27 #include <asm/i8259.h>
28 #include <asm/irq_cpu.h>
29 #include <asm/irq_regs.h>
30 #include <asm/mips-cm.h>
31 #include <asm/mips-boards/malta.h>
32 #include <asm/mips-boards/maltaint.h>
33 #include <asm/gt64120.h>
34 #include <asm/mips-boards/generic.h>
35 #include <asm/mips-boards/msc01_pci.h>
36 #include <asm/msc01_ic.h>
37 #include <asm/setup.h>
38 #include <asm/rtlx.h>
39 
40 static void __iomem *_msc01_biu_base;
41 
42 static DEFINE_RAW_SPINLOCK(mips_irq_lock);
43 
44 static inline int mips_pcibios_iack(void)
45 {
46 	int irq;
47 
48 	/*
49 	 * Determine highest priority pending interrupt by performing
50 	 * a PCI Interrupt Acknowledge cycle.
51 	 */
52 	switch (mips_revision_sconid) {
53 	case MIPS_REVISION_SCON_SOCIT:
54 	case MIPS_REVISION_SCON_ROCIT:
55 	case MIPS_REVISION_SCON_SOCITSC:
56 	case MIPS_REVISION_SCON_SOCITSCP:
57 		MSC_READ(MSC01_PCI_IACK, irq);
58 		irq &= 0xff;
59 		break;
60 	case MIPS_REVISION_SCON_GT64120:
61 		irq = GT_READ(GT_PCI0_IACK_OFS);
62 		irq &= 0xff;
63 		break;
64 	case MIPS_REVISION_SCON_BONITO:
65 		/* The following will generate a PCI IACK cycle on the
66 		 * Bonito controller. It's a little bit kludgy, but it
67 		 * was the easiest way to implement it in hardware at
68 		 * the given time.
69 		 */
70 		BONITO_PCIMAP_CFG = 0x20000;
71 
72 		/* Flush Bonito register block */
73 		(void) BONITO_PCIMAP_CFG;
74 		iob();	  /* sync */
75 
76 		irq = __raw_readl((u32 *)_pcictrl_bonito_pcicfg);
77 		iob();	  /* sync */
78 		irq &= 0xff;
79 		BONITO_PCIMAP_CFG = 0;
80 		break;
81 	default:
82 		pr_emerg("Unknown system controller.\n");
83 		return -1;
84 	}
85 	return irq;
86 }
87 
88 static inline int get_int(void)
89 {
90 	unsigned long flags;
91 	int irq;
92 	raw_spin_lock_irqsave(&mips_irq_lock, flags);
93 
94 	irq = mips_pcibios_iack();
95 
96 	/*
97 	 * The only way we can decide if an interrupt is spurious
98 	 * is by checking the 8259 registers.  This needs a spinlock
99 	 * on an SMP system,  so leave it up to the generic code...
100 	 */
101 
102 	raw_spin_unlock_irqrestore(&mips_irq_lock, flags);
103 
104 	return irq;
105 }
106 
107 static void malta_hw0_irqdispatch(void)
108 {
109 	int irq;
110 
111 	irq = get_int();
112 	if (irq < 0) {
113 		/* interrupt has already been cleared */
114 		return;
115 	}
116 
117 	do_IRQ(MALTA_INT_BASE + irq);
118 
119 #ifdef CONFIG_MIPS_VPE_APSP_API_MT
120 	if (aprp_hook)
121 		aprp_hook();
122 #endif
123 }
124 
125 static irqreturn_t i8259_handler(int irq, void *dev_id)
126 {
127 	malta_hw0_irqdispatch();
128 	return IRQ_HANDLED;
129 }
130 
131 static void corehi_irqdispatch(void)
132 {
133 	unsigned int intedge, intsteer, pcicmd, pcibadaddr;
134 	unsigned int pcimstat, intisr, inten, intpol;
135 	unsigned int intrcause, datalo, datahi;
136 	struct pt_regs *regs = get_irq_regs();
137 
138 	pr_emerg("CoreHI interrupt, shouldn't happen, we die here!\n");
139 	pr_emerg("epc	 : %08lx\nStatus: %08lx\n"
140 		 "Cause : %08lx\nbadVaddr : %08lx\n",
141 		 regs->cp0_epc, regs->cp0_status,
142 		 regs->cp0_cause, regs->cp0_badvaddr);
143 
144 	/* Read all the registers and then print them as there is a
145 	   problem with interspersed printk's upsetting the Bonito controller.
146 	   Do it for the others too.
147 	*/
148 
149 	switch (mips_revision_sconid) {
150 	case MIPS_REVISION_SCON_SOCIT:
151 	case MIPS_REVISION_SCON_ROCIT:
152 	case MIPS_REVISION_SCON_SOCITSC:
153 	case MIPS_REVISION_SCON_SOCITSCP:
154 		ll_msc_irq();
155 		break;
156 	case MIPS_REVISION_SCON_GT64120:
157 		intrcause = GT_READ(GT_INTRCAUSE_OFS);
158 		datalo = GT_READ(GT_CPUERR_ADDRLO_OFS);
159 		datahi = GT_READ(GT_CPUERR_ADDRHI_OFS);
160 		pr_emerg("GT_INTRCAUSE = %08x\n", intrcause);
161 		pr_emerg("GT_CPUERR_ADDR = %02x%08x\n",
162 				datahi, datalo);
163 		break;
164 	case MIPS_REVISION_SCON_BONITO:
165 		pcibadaddr = BONITO_PCIBADADDR;
166 		pcimstat = BONITO_PCIMSTAT;
167 		intisr = BONITO_INTISR;
168 		inten = BONITO_INTEN;
169 		intpol = BONITO_INTPOL;
170 		intedge = BONITO_INTEDGE;
171 		intsteer = BONITO_INTSTEER;
172 		pcicmd = BONITO_PCICMD;
173 		pr_emerg("BONITO_INTISR = %08x\n", intisr);
174 		pr_emerg("BONITO_INTEN = %08x\n", inten);
175 		pr_emerg("BONITO_INTPOL = %08x\n", intpol);
176 		pr_emerg("BONITO_INTEDGE = %08x\n", intedge);
177 		pr_emerg("BONITO_INTSTEER = %08x\n", intsteer);
178 		pr_emerg("BONITO_PCICMD = %08x\n", pcicmd);
179 		pr_emerg("BONITO_PCIBADADDR = %08x\n", pcibadaddr);
180 		pr_emerg("BONITO_PCIMSTAT = %08x\n", pcimstat);
181 		break;
182 	}
183 
184 	die("CoreHi interrupt", regs);
185 }
186 
187 static irqreturn_t corehi_handler(int irq, void *dev_id)
188 {
189 	corehi_irqdispatch();
190 	return IRQ_HANDLED;
191 }
192 
193 #ifdef CONFIG_MIPS_MT_SMP
194 
195 #define MIPS_CPU_IPI_RESCHED_IRQ 0	/* SW int 0 for resched */
196 #define C_RESCHED C_SW0
197 #define MIPS_CPU_IPI_CALL_IRQ 1		/* SW int 1 for resched */
198 #define C_CALL C_SW1
199 static int cpu_ipi_resched_irq, cpu_ipi_call_irq;
200 
201 static void ipi_resched_dispatch(void)
202 {
203 	do_IRQ(MIPS_CPU_IRQ_BASE + MIPS_CPU_IPI_RESCHED_IRQ);
204 }
205 
206 static void ipi_call_dispatch(void)
207 {
208 	do_IRQ(MIPS_CPU_IRQ_BASE + MIPS_CPU_IPI_CALL_IRQ);
209 }
210 
211 static irqreturn_t ipi_resched_interrupt(int irq, void *dev_id)
212 {
213 #ifdef CONFIG_MIPS_VPE_APSP_API_CMP
214 	if (aprp_hook)
215 		aprp_hook();
216 #endif
217 
218 	scheduler_ipi();
219 
220 	return IRQ_HANDLED;
221 }
222 
223 static irqreturn_t ipi_call_interrupt(int irq, void *dev_id)
224 {
225 	generic_smp_call_function_interrupt();
226 
227 	return IRQ_HANDLED;
228 }
229 
230 static struct irqaction irq_resched = {
231 	.handler	= ipi_resched_interrupt,
232 	.flags		= IRQF_PERCPU,
233 	.name		= "IPI_resched"
234 };
235 
236 static struct irqaction irq_call = {
237 	.handler	= ipi_call_interrupt,
238 	.flags		= IRQF_PERCPU,
239 	.name		= "IPI_call"
240 };
241 #endif /* CONFIG_MIPS_MT_SMP */
242 
243 static struct irqaction i8259irq = {
244 	.handler = i8259_handler,
245 	.name = "XT-PIC cascade",
246 	.flags = IRQF_NO_THREAD,
247 };
248 
249 static struct irqaction corehi_irqaction = {
250 	.handler = corehi_handler,
251 	.name = "CoreHi",
252 	.flags = IRQF_NO_THREAD,
253 };
254 
255 static msc_irqmap_t msc_irqmap[] __initdata = {
256 	{MSC01C_INT_TMR,		MSC01_IRQ_EDGE, 0},
257 	{MSC01C_INT_PCI,		MSC01_IRQ_LEVEL, 0},
258 };
259 static int msc_nr_irqs __initdata = ARRAY_SIZE(msc_irqmap);
260 
261 static msc_irqmap_t msc_eicirqmap[] __initdata = {
262 	{MSC01E_INT_SW0,		MSC01_IRQ_LEVEL, 0},
263 	{MSC01E_INT_SW1,		MSC01_IRQ_LEVEL, 0},
264 	{MSC01E_INT_I8259A,		MSC01_IRQ_LEVEL, 0},
265 	{MSC01E_INT_SMI,		MSC01_IRQ_LEVEL, 0},
266 	{MSC01E_INT_COREHI,		MSC01_IRQ_LEVEL, 0},
267 	{MSC01E_INT_CORELO,		MSC01_IRQ_LEVEL, 0},
268 	{MSC01E_INT_TMR,		MSC01_IRQ_EDGE, 0},
269 	{MSC01E_INT_PCI,		MSC01_IRQ_LEVEL, 0},
270 	{MSC01E_INT_PERFCTR,		MSC01_IRQ_LEVEL, 0},
271 	{MSC01E_INT_CPUCTR,		MSC01_IRQ_LEVEL, 0}
272 };
273 
274 static int msc_nr_eicirqs __initdata = ARRAY_SIZE(msc_eicirqmap);
275 
276 void __init arch_init_ipiirq(int irq, struct irqaction *action)
277 {
278 	setup_irq(irq, action);
279 	irq_set_handler(irq, handle_percpu_irq);
280 }
281 
282 void __init arch_init_irq(void)
283 {
284 	int corehi_irq, i8259_irq;
285 
286 	init_i8259_irqs();
287 
288 	if (!cpu_has_veic)
289 		mips_cpu_irq_init();
290 
291 	if (mips_cm_present()) {
292 		write_gcr_gic_base(GIC_BASE_ADDR | CM_GCR_GIC_BASE_GICEN_MSK);
293 		gic_present = 1;
294 	} else {
295 		if (mips_revision_sconid == MIPS_REVISION_SCON_ROCIT) {
296 			_msc01_biu_base = ioremap_nocache(MSC01_BIU_REG_BASE,
297 						MSC01_BIU_ADDRSPACE_SZ);
298 			gic_present =
299 			  (__raw_readl(_msc01_biu_base + MSC01_SC_CFG_OFS) &
300 			   MSC01_SC_CFG_GICPRES_MSK) >>
301 			  MSC01_SC_CFG_GICPRES_SHF;
302 		}
303 	}
304 	if (gic_present)
305 		pr_debug("GIC present\n");
306 
307 	switch (mips_revision_sconid) {
308 	case MIPS_REVISION_SCON_SOCIT:
309 	case MIPS_REVISION_SCON_ROCIT:
310 		if (cpu_has_veic)
311 			init_msc_irqs(MIPS_MSC01_IC_REG_BASE,
312 					MSC01E_INT_BASE, msc_eicirqmap,
313 					msc_nr_eicirqs);
314 		else
315 			init_msc_irqs(MIPS_MSC01_IC_REG_BASE,
316 					MSC01C_INT_BASE, msc_irqmap,
317 					msc_nr_irqs);
318 		break;
319 
320 	case MIPS_REVISION_SCON_SOCITSC:
321 	case MIPS_REVISION_SCON_SOCITSCP:
322 		if (cpu_has_veic)
323 			init_msc_irqs(MIPS_SOCITSC_IC_REG_BASE,
324 					MSC01E_INT_BASE, msc_eicirqmap,
325 					msc_nr_eicirqs);
326 		else
327 			init_msc_irqs(MIPS_SOCITSC_IC_REG_BASE,
328 					MSC01C_INT_BASE, msc_irqmap,
329 					msc_nr_irqs);
330 	}
331 
332 	if (gic_present) {
333 		int i;
334 
335 		gic_init(GIC_BASE_ADDR, GIC_ADDRSPACE_SZ, MIPSCPU_INT_GIC,
336 			 MIPS_GIC_IRQ_BASE);
337 		if (!mips_cm_present()) {
338 			/* Enable the GIC */
339 			i = __raw_readl(_msc01_biu_base + MSC01_SC_CFG_OFS);
340 			__raw_writel(i | (0x1 << MSC01_SC_CFG_GICENA_SHF),
341 				 _msc01_biu_base + MSC01_SC_CFG_OFS);
342 			pr_debug("GIC Enabled\n");
343 		}
344 		i8259_irq = MIPS_GIC_IRQ_BASE + GIC_INT_I8259A;
345 		corehi_irq = MIPS_CPU_IRQ_BASE + MIPSCPU_INT_COREHI;
346 	} else {
347 #if defined(CONFIG_MIPS_MT_SMP)
348 		/* set up ipi interrupts */
349 		if (cpu_has_veic) {
350 			set_vi_handler (MSC01E_INT_SW0, ipi_resched_dispatch);
351 			set_vi_handler (MSC01E_INT_SW1, ipi_call_dispatch);
352 			cpu_ipi_resched_irq = MSC01E_INT_SW0;
353 			cpu_ipi_call_irq = MSC01E_INT_SW1;
354 		} else {
355 			cpu_ipi_resched_irq = MIPS_CPU_IRQ_BASE +
356 				MIPS_CPU_IPI_RESCHED_IRQ;
357 			cpu_ipi_call_irq = MIPS_CPU_IRQ_BASE +
358 				MIPS_CPU_IPI_CALL_IRQ;
359 		}
360 		arch_init_ipiirq(cpu_ipi_resched_irq, &irq_resched);
361 		arch_init_ipiirq(cpu_ipi_call_irq, &irq_call);
362 #endif
363 		if (cpu_has_veic) {
364 			set_vi_handler(MSC01E_INT_I8259A,
365 				       malta_hw0_irqdispatch);
366 			set_vi_handler(MSC01E_INT_COREHI,
367 				       corehi_irqdispatch);
368 			i8259_irq = MSC01E_INT_BASE + MSC01E_INT_I8259A;
369 			corehi_irq = MSC01E_INT_BASE + MSC01E_INT_COREHI;
370 		} else {
371 			i8259_irq = MIPS_CPU_IRQ_BASE + MIPSCPU_INT_I8259A;
372 			corehi_irq = MIPS_CPU_IRQ_BASE + MIPSCPU_INT_COREHI;
373 		}
374 	}
375 
376 	setup_irq(i8259_irq, &i8259irq);
377 	setup_irq(corehi_irq, &corehi_irqaction);
378 }
379 
380 void malta_be_init(void)
381 {
382 	/* Could change CM error mask register. */
383 }
384 
385 int malta_be_handler(struct pt_regs *regs, int is_fixup)
386 {
387 	/* This duplicates the handling in do_be which seems wrong */
388 	int retval = is_fixup ? MIPS_BE_FIXUP : MIPS_BE_FATAL;
389 
390 	mips_cm_error_report();
391 
392 	return retval;
393 }
394