1 /******************************************************************************
2  *
3  * Name:	skgehwt.c
4  * Project:	Gigabit Ethernet Adapters, Event Scheduler Module
5  * Purpose:	Hardware Timer
6  *
7  ******************************************************************************/
8 
9 /******************************************************************************
10  *
11  *	(C)Copyright 1998-2002 SysKonnect GmbH.
12  *	(C)Copyright 2002-2003 Marvell.
13  *
14  *	This program is free software; you can redistribute it and/or modify
15  *	it under the terms of the GNU General Public License as published by
16  *	the Free Software Foundation; either version 2 of the License, or
17  *	(at your option) any later version.
18  *
19  *	The information in this file is provided "AS IS" without warranty.
20  *
21  ******************************************************************************/
22 
23 /*
24  *	Event queue and dispatcher
25  */
26 #if (defined(DEBUG) || ((!defined(LINT)) && (!defined(SK_SLIM))))
27 static const char SysKonnectFileId[] =
28 	"@(#) $Id: skgehwt.c,v 1.15 2003/09/16 13:41:23 rschmidt Exp $ (C) Marvell.";
29 #endif
30 
31 #include "h/skdrv1st.h"		/* Driver Specific Definitions */
32 #include "h/skdrv2nd.h"		/* Adapter Control- and Driver specific Def. */
33 
34 #ifdef __C2MAN__
35 /*
36  *   Hardware Timer function queue management.
37  */
intro()38 intro()
39 {}
40 #endif
41 
42 /*
43  * Prototypes of local functions.
44  */
45 #define	SK_HWT_MAX	(65000)
46 
47 /* correction factor */
48 #define	SK_HWT_FAC	(1000 * (SK_U32)pAC->GIni.GIHstClkFact / 100)
49 
50 /*
51  * Initialize hardware timer.
52  *
53  * Must be called during init level 1.
54  */
SkHwtInit(SK_AC * pAC,SK_IOC Ioc)55 void	SkHwtInit(
56 SK_AC	*pAC,	/* Adapters context */
57 SK_IOC	Ioc)	/* IoContext */
58 {
59 	pAC->Hwt.TStart = 0 ;
60 	pAC->Hwt.TStop	= 0 ;
61 	pAC->Hwt.TActive = SK_FALSE;
62 
63 	SkHwtStop(pAC, Ioc);
64 }
65 
66 /*
67  *
68  * Start hardware timer (clock ticks are 16us).
69  *
70  */
SkHwtStart(SK_AC * pAC,SK_IOC Ioc,SK_U32 Time)71 void	SkHwtStart(
72 SK_AC	*pAC,	/* Adapters context */
73 SK_IOC	Ioc,	/* IoContext */
74 SK_U32	Time)	/* Time in units of 16us to load the timer with. */
75 {
76 	SK_U32	Cnt;
77 
78 	if (Time > SK_HWT_MAX)
79 		Time = SK_HWT_MAX;
80 
81 	pAC->Hwt.TStart = Time;
82 	pAC->Hwt.TStop = 0L;
83 
84 	Cnt = Time;
85 
86 	/*
87 	 * if time < 16 us
88 	 *	time = 16 us
89 	 */
90 	if (!Cnt) {
91 		Cnt++;
92 	}
93 
94 	SK_OUT32(Ioc, B2_TI_INI, Cnt * SK_HWT_FAC);
95 
96 	SK_OUT16(Ioc, B2_TI_CTRL, TIM_START);	/* Start timer. */
97 
98 	pAC->Hwt.TActive = SK_TRUE;
99 }
100 
101 /*
102  * Stop hardware timer.
103  * and clear the timer IRQ
104  */
SkHwtStop(SK_AC * pAC,SK_IOC Ioc)105 void	SkHwtStop(
106 SK_AC	*pAC,	/* Adapters context */
107 SK_IOC	Ioc)	/* IoContext */
108 {
109 	SK_OUT16(Ioc, B2_TI_CTRL, TIM_STOP);
110 
111 	SK_OUT16(Ioc, B2_TI_CTRL, TIM_CLR_IRQ);
112 
113 	pAC->Hwt.TActive = SK_FALSE;
114 }
115 
116 
117 /*
118  *	Stop hardware timer and read time elapsed since last start.
119  *
120  * returns
121  *	The elapsed time since last start in units of 16us.
122  *
123  */
SkHwtRead(SK_AC * pAC,SK_IOC Ioc)124 SK_U32	SkHwtRead(
125 SK_AC	*pAC,	/* Adapters context */
126 SK_IOC	Ioc)	/* IoContext */
127 {
128 	SK_U32	TRead;
129 	SK_U32	IStatus;
130 
131 	if (pAC->Hwt.TActive) {
132 
133 		SkHwtStop(pAC, Ioc);
134 
135 		SK_IN32(Ioc, B2_TI_VAL, &TRead);
136 		TRead /= SK_HWT_FAC;
137 
138 		SK_IN32(Ioc, B0_ISRC, &IStatus);
139 
140 		/* Check if timer expired (or wraped around) */
141 		if ((TRead > pAC->Hwt.TStart) || (IStatus & IS_TIMINT)) {
142 
143 			SkHwtStop(pAC, Ioc);
144 
145 			pAC->Hwt.TStop = pAC->Hwt.TStart;
146 		}
147 		else {
148 
149 			pAC->Hwt.TStop = pAC->Hwt.TStart - TRead;
150 		}
151 	}
152 	return(pAC->Hwt.TStop);
153 }
154 
155 /*
156  * interrupt source= timer
157  */
SkHwtIsr(SK_AC * pAC,SK_IOC Ioc)158 void	SkHwtIsr(
159 SK_AC	*pAC,	/* Adapters context */
160 SK_IOC	Ioc)	/* IoContext */
161 {
162 	SkHwtStop(pAC, Ioc);
163 
164 	pAC->Hwt.TStop = pAC->Hwt.TStart;
165 
166 	SkTimerDone(pAC, Ioc);
167 }
168 
169 /* End of file */
170