Changeset 294 for soft/giet_vm/giet_kernel/ctx_handler.h

Timestamp:

Mar 26, 2014, 6:10:01 PM (10 years ago)

Author:

alain

Message:

Introducing support for IOPIC component.

File:

• soft/giet_vm/giet_kernel/ctx_handler.h (modified) (7 diffs)

soft/giet_vm/giet_kernel/ctx_handler.h

@@ +1 @@
+/////////////////////////////////////////////////////////////////////////////////////////
+// File     : ctx_handler.h
+// Date     : 01/04/2012
+// Authors  : alain greiner & joel porquet
+// Copyright (c) UPMC-LIP6
+/////////////////////////////////////////////////////////////////////////////////////////
+// The ctx_handler.h and ctx_handler.c files are part of the GIET-VM nano-kernel.
+// This code is used to support context switch when several tasks are executing
+// in time multiplexing on a single processor.
+// The tasks are statically allocated to a processor in the boot phase, and
+// there is one private scheduler per processor. Each sheduler occupies 4K bytes, 
+// and contains up to 14 task contexts (task_id is from 0 to 13).
+// The task context [13] is reserved for the "idle" task that does nothing, and
+// is launched by the scheduler when there is no other runable task.
+/////////////////////////////////////////////////////////////////////////////////////////
+// A task context is an array of 64 words = 256 bytes. 
+// It contains copies of processor registers (when the task is preempted):
+// - GPR[i], generally stored in slot (i). $0, $26 & $27 are not saved.
+// - HI & LO registers
+// - CP0 registers: EPC, SR, CR, BVAR 
+// - CP2 registers : PTPR 
+// It contains some general informations associated to the task:
+// - TTY    : TTY channel global index
+// - NIC    : NIC channel global index
+// - CMA    : CMA channel global index
+// - HBA    : HBA channel global index
+// - DMA    : DMA channel local index
+// - TIM    : TIM channel local index
+// - PTAB   : page table virtual base address 
+// - LTID   : Task local index (in scheduler)
+// - VSID   : Virtual space index
+// - RUN    : Task state (0 => sleeping / 1 => runnable ) 
+// - TRDID  : Thread ID index (in vspace)
+//
+// ctx[0] <- ***   |ctx[8] <- $8    |ctx[16]<- $16   |ctx[24]<- $24
+// ctx[1] <- $1    |ctx[9] <- $9    |ctx[17]<- $17   |ctx[25]<- $25
+// ctx[2] <- $2    |ctx[10]<- $10   |ctx[18]<- $18   |ctx[26]<- LO
+// ctx[3] <- $3    |ctx[11]<- $11   |ctx[19]<- $19   |ctx[27]<- HI
+// ctx[4] <- $4    |ctx[12]<- $12   |ctx[20]<- $20   |ctx[28]<- $28
+// ctx[5] <- $5    |ctx[13]<- $13   |ctx[21]<- $21   |ctx[29]<- SP
+// ctx[6] <- $6    |ctx[14]<- $14   |ctx[22]<- $22   |ctx[30]<- $30
+// ctx[7] <- $7    |ctx[15]<- $15   |ctx[23]<- $23   |ctx[31]<- RA
+//
+// ctx[32]<- EPC   |ctx[40]<- TTY   |ctx[48]<- TRDID |
+// ctx[33]<- CR    |ctx[41]<- DMA
+// ctx[34]<- SR    |ctx[42]<- NIC
+// ctx[35]<- BVAR  |ctx[43]<- TIM
+// ctx[36]<- PTAB  |ctx[44]<- HBA
+// ctx[37]<- LTID  |ctx[45]<- CMA 
+// ctx[38]<- VSID  |ctx[46]<- GTID
+// ctx[39]<- PTPR  |ctx[47]<- RUN
+/////////////////////////////////////////////////////////////////////////////////////////
+
 #ifndef _CTX_HANDLER_H
 #define _CTX_HANDLER_H
@@ -10 +63 @@
 typedef struct static_scheduler_s 
 {
-    unsigned int context[15][64];      // at most 15 task contexts
+    unsigned int context[14][64];      // at most 14 task (including idle_task)
     unsigned int tasks;                // actual number of tasks
     unsigned int current;              // current task index
-    unsigned int interrupt_vector[32]; // interrupt vector
+    unsigned int hwi_vector[32];       // hardware interrupt vector
+    unsigned int pti_vector[32];       // timer    interrupt vector
+    unsigned int wti_vector[32];       // software interrupt vector
 } static_scheduler_t;
 
@@ -21 +76 @@
 /////////////////////////////////////////////////////////////////////////////////
 
-#define IDLE_TASK_INDEX        14
+#define IDLE_TASK_INDEX        13
 
 /////////////////////////////////////////////////////////////////////////////////
@@ -27 +82 @@
 /////////////////////////////////////////////////////////////////////////////////
 
-#define CTX_SP_ID        29
-#define CTX_RA_ID        31
+#define CTX_SP_ID        29  // Stack Pointer
+#define CTX_RA_ID        31  // Return Address
 
 #define CTX_EPC_ID       32  // Exception Program Counter (CP0)
@@ -34 +89 @@
 #define CTX_SR_ID        34  // Status Register (CP0)
 #define CTX_BVAR_ID      35      // Bad Virtual Address Register (CP0)
-
 #define CTX_PTAB_ID      36  // Page Table Virtual address
 #define CTX_LTID_ID      37  // Local  Task Index (in scheduler)
@@ -40 +94 @@
 #define CTX_PTPR_ID      39  // Page Table Pointer Register (PADDR>>13)
 
-#define CTX_TTY_ID       40  // global TTY terminal  
+#define CTX_TTY_ID       40  // global TTY channel   
 #define CTX_DMA_ID       41  // local DMA channel 
 #define CTX_NIC_ID       42  // global NIC channel 
@@ -48 +102 @@
 #define CTX_GTID_ID      46  // Global Task Index
 #define CTX_RUN_ID       47  // Boolean: task runable
+
 #define CTX_TRDID_ID     48  // Thread Index in vspace