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source: soft/giet_vm/giet_kernel/kernel_init.c @ 404

Last change on this file since 404 was 396, checked in by alain, 10 years ago
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1	///////////////////////////////////////////////////////////////////////////////////
2	// File : kernel_init.c
3	// Date : 26/05/2012
4	// Authors : alain greiner & mohamed karaoui
5	// Copyright (c) UPMC-LIP6
6	////////////////////////////////////////////////////////////////////////////////////
7	// The kernel_init.c file is part of the GIET-VM nano-kernel.
8	//
9	// This nano-kernel has been written for the MIPS32 processor.
10	// The virtual adresses are on 32 bits and use the (unsigned int) type, but the
11	// physicals addresses can have up to 40 bits, and use the (unsigned long long) type.
12	// It natively supports clusterised shared mmemory multi-processors architectures,
13	// where each processor is identified by a composite index [x,y,lpid],
14	// and where there is one physical memory bank per cluster.
15	//
16	// The kernel_init() function is executed sequencially by all procesors.
17	// It completes the system initialisation that has been started by processor[0,0,0]
18	// in the boot_init() function. It makes the following assuptions, regarding the work
19	// bone by the boot code:
20	//
21	// 1) The page tables associated to the various vspaces have been build
22	// in physical memory, and can be used by the kernel code.
23	//
24	// 2) All schedulers (this include all task contexts) have been initialised,
25	// Both the virtual and the physical base addresses of the page tables
26	// are available in the CTX_PTAB and CTX_PTPR slots.
27	//
28	// 3) The CP0_SCHED register of each processor contains a pointer on its
29	// private scheduler (virtual address).
30	//
31	// 4) The CP2_PTPR register of each processor contains a pointer on
32	// the vspace_0 page table (physical address>>13).
33	//
34	// 5) For all processors, the MMU is activated (CP2_MODE contains 0xF).
35	//
36	// This code must be loaded in .kinit section, in order to control seg_kinit_base,
37	// as this address is used by the boot code to jump into kernel code.
38	//
39	// Each processor performs the following actions:
40	// 1/ contribute to _schedulers_paddr[] array initialisation.
41	// 2/ contribute to _ptabs_paddr[] and _ptabs_vaddr arrays initialisation
42	// 3/ completes task context initialisation for ech allocated task
43	// 4/ compute and set the ICU mask for its private ICU channel
44	// 5/ initialise its private TICK timer (if tasks > 0)
45	// 6/ initialise the "idle" task context in its private scheduler
46	// 7/ initialise SP, SR, PTPR, EPC registers and jump to user code with an eret.
47	////////////////////////////////////////////////////////////////////////////////////
48
49	#include <giet_config.h>
50
51	// kernel libraries
52	#include <utils.h>
53	#include <fat32.h>
54
55	//for peripheral initialisation
56	#include <dma_driver.h>
57	#include <fbf_driver.h>
58	#include <tty_driver.h>
59	#include <icu_driver.h>
60	#include <xcu_driver.h>
61	#include <ioc_driver.h>
62	#include <mmc_driver.h>
63	#include <mwr_driver.h>
64	#include <nic_driver.h>
65	#include <tim_driver.h>
66
67	#include <ctx_handler.h>
68	#include <irq_handler.h>
69
70	#include <mapping_info.h>
71	#include <mips32_registers.h>
72
73	#if !defined(X_SIZE)
74	# error: You must define X_SIZE in the hard_config.h file
75	#endif
76
77	#if !defined(Y_SIZE)
78	# error: You must define Y_SIZE in the hard_config.h file
79	#endif
80
81	#if !defined(Y_WIDTH)
82	# error: You must define Y_WIDTH in the hard_config.h file
83	#endif
84
85	#if !defined(Y_WIDTH)
86	# error: You must define Y_WIDTH in the hard_config.h file
87	#endif
88
89	#if !defined(NB_PROCS_MAX)
90	# error: You must define NB_PROCS_MAX in the hard_config.h file
91	#endif
92
93	#if !defined(NB_TOTAL_PROCS)
94	# error: You must define NB_TOTAL_PROCS in the hard_config.h file
95	#endif
96
97	#if !defined(USE_XCU)
98	# error: You must define USE_XCU in the hard_config.h file
99	#endif
100
101	#if !defined(IDLE_TASK_INDEX)
102	# error: You must define IDLE_TASK_INDEX in the ctx_handler.h file
103	#endif
104
105	#if !defined(GIET_TICK_VALUE)
106	# error: You must define GIET_TICK_VALUE in the giet_config.h file
107	#endif
108
109	#if !defined(GIET_NB_VSPACE_MAX)
110	# error: You must define GIET_NB_VSPACE_MAX in the giet_config.h file
111	#endif
112
113	///////////////////////////////////////////////////////////////////////////////////
114	// array of pointers on the page tables (virtual addresses)
115	///////////////////////////////////////////////////////////////////////////////////
116
117	__attribute__((section (".kdata")))
118	volatile unsigned int _ptabs_vaddr[GIET_NB_VSPACE_MAX]; // virtual addresses
119
120	__attribute__((section (".kdata")))
121	volatile unsigned int _ptabs_ptprs[GIET_NB_VSPACE_MAX]; // physical addresses >> 13
122
123	///////////////////////////////////////////////////////////////////////////////////
124	// array of pointers on the schedulers (physical addresses)
125	///////////////////////////////////////////////////////////////////////////////////
126
127	__attribute__((section (".kdata")))
128	volatile static_scheduler_t* _schedulers[NB_PROCS_MAX<<(X_WIDTH+Y_WIDTH)];
129
130	////////////////////////////////////////////////////////////////////////////////////
131	// Synchonisation barrier before jumping to user code
132	////////////////////////////////////////////////////////////////////////////////////
133
134	__attribute__((section (".kdata")))
135	volatile unsigned int _init_barrier = 0;
136
137	///////////////////////////////////////////////////////////////////////////////////
138	__attribute__((section (".kinit"))) void kernel_init()
139	{
140	unsigned int global_pid = _get_procid();
141	unsigned int cluster_xy = global_pid / NB_PROCS_MAX;
142	unsigned int x = cluster_xy >> Y_WIDTH;
143	unsigned int y = cluster_xy & ((1<<Y_WIDTH)-1);
144	unsigned int lpid = global_pid % NB_PROCS_MAX;
145	unsigned int pid = ((( x * Y_SIZE) + y) * NB_PROCS_MAX) + lpid;
146
147	// This last initialisation phase is done sequencially:
148	while( pid != _init_barrier ) asm volatile ( "nop" );
149
150	// Step 1 : each processor get its scheduler virtual address from CP0 register
151	// and contribute to initialise the _schedulers[] array
152
153	static_scheduler_t* psched = (static_scheduler_t*)_get_sched();
154	unsigned int tasks = psched->tasks;
155
156	_schedulers[global_pid] = psched;
157
158	#if GIET_DEBUG_INIT
159	_printf("\n[GIET DEBUG INIT] Processor[%d,%d,%d] starts kernel init\n"
160	" - scheduler vbase = %x\n"
161	" - tasks = %d\n",
162	x, y, lpid, (unsigned int)psched, tasks );
163	#endif
164
165	// step 2 : each processor that is allocated at least one task loops
166	// on all allocated tasks:
167	// - contributes to _ptabs_vaddr[] & _ptabs_ptprs[] initialisation.
168	// - set CTX_RA slot with the kernel _ctx_eret() virtual address.
169	// - set CTX_EPC slot that must contain the task entry point,
170	// and contain only at this point the virtual address of the memory
171	// location containing this entry point. We must switch the PTPR
172	// to use the page table corresponding to the task.
173
174	unsigned int ltid;
175
176	for (ltid = 0; ltid < tasks; ltid++)
177	{
178	unsigned int vsid = _get_task_slot( global_pid, ltid , CTX_VSID_ID );
179	unsigned int ptab = _get_task_slot( global_pid, ltid , CTX_PTAB_ID );
180	unsigned int ptpr = _get_task_slot( global_pid, ltid , CTX_PTPR_ID );
181
182	// initialize PTABS arrays
183	_ptabs_vaddr[vsid] = ptab;
184	_ptabs_ptprs[vsid] = ptpr;
185
186	#if GIET_DEBUG_INIT
187	_printf("\n[GIET DEBUG INIT] Processor[%d,%d,%d] contributes to PTABS arrays\n"
188	" - ptabs_vaddr[%d] = %x / ptpr_paddr[%d] = %l\n",
189	x, y, lpid,
190	vsid, ptab, vsid, ((unsigned long long)ptpr)<<13 );
191	#endif
192
193	// set the ptpr to use the task page table
194	asm volatile( "mtc2 %0, $0 \n"
195	: : "r" (ptpr) );
196
197	// compute ctx_ra
198	unsigned int ctx_ra = (unsigned int)(&_ctx_eret);
199	_set_task_slot( global_pid, ltid, CTX_RA_ID, ctx_ra );
200
201	// compute ctx_epc
202	unsigned int* ptr = (unsigned int*)_get_task_slot( global_pid, ltid, CTX_EPC_ID );
203	_set_task_slot( global_pid, ltid, CTX_EPC_ID, *ptr );
204
205	#if GIET_DEBUG_INIT
206	_printf("\n[GIET DEBUG INIT] Processor[%d,%d,%d] updates context for task %d\n"
207	" - ctx_epc = %x\n"
208	" - ctx_ra = %x\n",
209	x, y, lpid, ltid,
210	_get_task_slot( global_pid, ltid, CTX_EPC_ID ),
211	_get_task_slot( global_pid, ltid, CTX_RA_ID ) );
212	#endif
213
214	} // end for tasks
215
216	// step 4 : compute and set ICU or XCU masks
217
218	unsigned int isr_switch_index = 0xFFFFFFFF;
219	unsigned int hwi_mask = 0;
220	unsigned int pti_mask = 0;
221	unsigned int wti_mask = 0;
222	unsigned int irq_id; // IN_IRQ index
223	unsigned int entry; // interrupt vector entry
224
225	for (irq_id = 0; irq_id < 32; irq_id++)
226	{
227	entry = psched->hwi_vector[irq_id];
228	if ( entry & 0x80000000 ) hwi_mask = hwi_mask \| (1<<irq_id);
229	if ( (entry & 0x0000FFFF) == ISR_TICK ) isr_switch_index = irq_id;
230
231	entry = psched->pti_vector[irq_id];
232	if ( entry & 0x80000000 ) pti_mask = pti_mask \| (1<<irq_id);
233	if ( (entry & 0x0000FFFF) == ISR_TICK ) isr_switch_index = irq_id;
234
235	entry = psched->wti_vector[irq_id];
236	if ( entry & 0x80000000 ) wti_mask = wti_mask \| (1<<irq_id);
237	if ( (entry & 0x0000FFFF) == ISR_TICK ) isr_switch_index = irq_id;
238	}
239
240	#if GIET_DEBUG_INIT
241	_printf("\n[GIET DEBUG INIT] Processor[%d,%d,%d] sets XCU masks\n"
242	" - ICU HWI_MASK = %x\n"
243	" - ICU WTI_MASK = %x\n"
244	" - ICU PTI_MASK = %x\n",
245	x, y, lpid, hwi_mask, wti_mask, pti_mask );
246	#endif
247
248	unsigned int channel = lpid * IRQ_PER_PROCESSOR;
249
250	#if USE_XCU
251	_xcu_set_mask( cluster_xy, channel, hwi_mask, IRQ_TYPE_HWI );
252	_xcu_set_mask( cluster_xy, channel, wti_mask, IRQ_TYPE_WTI );
253	_xcu_set_mask( cluster_xy, channel, pti_mask, IRQ_TYPE_PTI );
254	#else
255	_icu_set_mask( cluster_xy, channel, hwi_mask );
256	#endif
257
258	// step 5 : start TICK timer if at least one task
259	if (tasks > 0)
260	{
261	// one ISR_TICK must be defined for each proc
262	if (isr_switch_index == 0xFFFFFFFF)
263	{
264	_printf("\n[GIET ERROR] ISR_TICK not found for processor[%d,%d,%d]\n",
265	x, y, lpid );
266	_exit();
267	}
268
269	// start system timer
270
271	#if USE_XCU
272	_xcu_timer_start( cluster_xy, isr_switch_index, GIET_TICK_VALUE );
273	#else
274	_timer_start( cluster_xy, isr_switch_index, GIET_TICK_VALUE );
275	#endif
276
277	}
278
279	#if GIET_DEBUG_INIT
280	_printf("\n[GIET DEBUG INIT] Processor[%d,%d,%d] starts TICK timer\n",
281	x, y, lpid );
282	#endif
283
284	// step 6 : each processor updates the idle_task context:
285	// (CTX_SP, CTX_RA, CTX_EPC).
286	// The 4 Kbytes idle stack is implemented in the scheduler.
287	// The PTPR register, the CTX_PTPR and CTX_PTAB slots
288	// have been initialised in boot code.
289
290	unsigned int pstack = ((unsigned int)psched) + 0x2000;
291
292	_set_task_slot( global_pid, IDLE_TASK_INDEX, CTX_SP_ID, pstack);
293	_set_task_slot( global_pid, IDLE_TASK_INDEX, CTX_RA_ID, (unsigned int) &_ctx_eret);
294	_set_task_slot( global_pid, IDLE_TASK_INDEX, CTX_EPC_ID, (unsigned int) &_idle_task);
295
296	#if GIET_DEBUG_INIT
297	_printf("\n[GIET DEBUG INIT] Processor[%d,%d,%d] initializes IDLE task\n"
298	" - stack_base = %x\n"
299	" - stack_size = 0x1000\n",
300	x, y, lpid, pstack - 0x1000 );
301	#endif
302
303	// step 7 : when all processors reach the synchronisation barrier,
304	// each processor set registers SP, SR, PTPR, EPC,
305	// with the values corresponding to the first allocated task,
306	// or to the idle_task if there is no task allocated,
307	// and jump to user code
308
309	if (tasks == 0)
310	{
311	ltid = IDLE_TASK_INDEX;
312
313	_printf("\n[GIET WARNING] No task allocated to processor[%d,%d,%d]\n",
314	x, y, lpid );
315	}
316	else
317	{
318	ltid = 0;
319	}
320
321	unsigned int sp_value = _get_task_slot(global_pid, ltid, CTX_SP_ID);
322	unsigned int sr_value = _get_task_slot(global_pid, ltid, CTX_SR_ID);
323	unsigned int ptpr_value = _get_task_slot(global_pid, ltid, CTX_PTPR_ID);
324	unsigned int epc_value = _get_task_slot(global_pid, ltid, CTX_EPC_ID);
325
326	#if GIET_DEBUG_INIT
327	_printf("\n[GIET DEBUG INIT] Processor[%d,%d,%d] reach barrier at cycle %d\n",
328	x, y, lpid, _get_proctime() );
329	#endif
330
331	// increment barrier counter
332	_init_barrier++;
333
334	// busy waiting until all processors synchronized
335	while ( _init_barrier != NB_TOTAL_PROCS );
336
337	#if GIET_DEBUG_INIT
338	_printf("\n[GIET DEBUG INIT] Processor[%d,%d,%d] initializes registers at cycle %d\n"
339	" - sp = %x\n"
340	" - sr = %x\n"
341	" - ptpr = %x\n"
342	" - epc = %x\n",
343	x, y, lpid, _get_proctime(),
344	sp_value, sr_value, ptpr_value, epc_value );
345	#endif
346
347	// set registers and jump to user code
348	asm volatile ( "move $29, %0 \n" /* SP <= ctx[CTX_SP_ID] */
349	"mtc0 %1, $12 \n" /* SR <= ctx[CTX_SR_ID] */
350	"mtc2 %2, $0 \n" /* PTPR <= ctx[CTX_PTPR] */
351	"mtc0 %3, $14 \n" /* EPC <= ctx[CTX_EPC] */
352	"eret \n" /* jump to user code */
353	"nop \n"
354	:
355	: "r"(sp_value), "r"(sr_value), "r"(ptpr_value), "r"(epc_value)
356	: "$29", "memory" );
357
358	} // end kernel_init()
359
360
361	// Local Variables:
362	// tab-width: 4
363	// c-basic-offset: 4
364	// c-file-offsets:((innamespace . 0)(inline-open . 0))
365	// indent-tabs-mode: nil
366	// End:
367	// vim: filetype=c:expandtab:shiftwidth=4:tabstop=4:softtabstop=4
368

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