source: rtems/c/src/lib/libbsp/sparc/leon3/amba/amba.c @ e428dc4a

4.115
Last change on this file since e428dc4a was e428dc4a, checked in by Daniel Hellstrom <daniel@…>, on 12/12/11 at 14:50:57

LEON3: implemented BSP DRVMGR startup initialization

  • Property mode set to 100644
File size: 5.2 KB
Line 
1/*
2 *  AMBA Plug & Play Bus Driver
3 *
4 *  This driver hook performs bus scanning.
5 *
6 *  COPYRIGHT (c) 2011.
7 *  Aeroflex Gaisler
8 *
9 *  The license and distribution terms for this file may be
10 *  found in the file LICENSE in this distribution or at
11 *  http://www.rtems.org/license/LICENSE.
12 */
13
14#include <bsp.h>
15#include <bsp/fatal.h>
16#include <leon.h>
17#include <ambapp.h>
18
19unsigned int leon3_timer_prescaler __attribute__((weak)) = 0;
20int leon3_timer_core_index __attribute__((weak)) = 0;
21
22/* AMBA Plug&Play information description.
23 *
24 * After software has scanned AMBA PnP it builds a tree to make
25 * it easier for drivers to work with the bus architecture.
26 */
27struct ambapp_bus ambapp_plb;
28
29/* If RTEMS_DRVMGR_STARTUP is defined extra code is added that
30 * registers the GRLIB AMBA PnP bus driver as root driver.
31 */
32#ifdef RTEMS_DRVMGR_STARTUP
33#include <drvmgr/drvmgr.h>
34#include <drvmgr/ambapp_bus_grlib.h>
35
36extern void gptimer_register_drv (void);
37extern void apbuart_cons_register_drv(void);
38/* All drivers included by BSP, this is overridden by the user by including
39 * the drvmgr_confdefs.h. By default the Timer and UART driver are included.
40 */
41struct drvmgr_drv_reg_func drvmgr_drivers[] __attribute__((weak)) =
42{
43  {gptimer_register_drv},
44  {apbuart_cons_register_drv},
45  {NULL} /* End array with NULL */
46};
47
48/* Driver resources configuration for AMBA root bus. It is declared weak
49 * so that the user may override it, if the defualt settings are not
50 * enough.
51 */
52struct drvmgr_bus_res grlib_drv_resources __attribute__((weak)) =
53{
54  .next = NULL,
55  .resource =
56  {
57    RES_EMPTY,
58  }
59};
60
61/* GRLIB AMBA bus configuration (the LEON3 root bus configuration) */
62struct grlib_config grlib_bus_config =
63{
64  &ambapp_plb,              /* AMBAPP bus setup */
65  &grlib_drv_resources,     /* Driver configuration */
66};
67#endif
68
69rtems_interrupt_lock LEON3_IrqCtrl_Lock =
70  RTEMS_INTERRUPT_LOCK_INITIALIZER("LEON3 IrqCtrl");
71
72/* Pointers to Interrupt Controller configuration registers */
73volatile struct irqmp_regs *LEON3_IrqCtrl_Regs;
74struct ambapp_dev *irqmp_dev;
75struct ambapp_dev *timer_dev;
76
77/*
78 *  amba_initialize
79 *
80 *  Must be called just before drivers are initialized.
81 *  Used to scan system bus. Probes for AHB masters, AHB slaves and
82 *  APB slaves. Addresses to configuration areas of the AHB masters,
83 *  AHB slaves, APB slaves and APB master are storeds in
84 *  amba_ahb_masters, amba_ahb_slaves and amba.
85 */
86
87void amba_initialize(void)
88{
89  int icsel;
90  struct ambapp_dev *adev;
91
92  /* Scan AMBA Plug&Play read-only information. The routine builds a PnP
93   * tree into ambapp_plb in RAM, after this we never access the PnP
94   * information in hardware directly any more.
95   * Since on Processor Local Bus (PLB) memory mapping is 1:1
96   */
97  ambapp_scan(&ambapp_plb, LEON3_IO_AREA, NULL, NULL);
98
99  /* Find LEON3 Interrupt controller */
100  adev = (void *)ambapp_for_each(&ambapp_plb, (OPTIONS_ALL|OPTIONS_APB_SLVS),
101                                 VENDOR_GAISLER, GAISLER_IRQMP,
102                                 ambapp_find_by_idx, NULL);
103  if (adev == NULL) {
104    /* PANIC IRQ controller not found!
105     *
106     *  What else can we do but stop ...
107     */
108    bsp_fatal(LEON3_FATAL_NO_IRQMP_CONTROLLER);
109  }
110
111  LEON3_IrqCtrl_Regs = (volatile struct irqmp_regs *)DEV_TO_APB(adev)->start;
112  irqmp_dev = adev;
113  if ((LEON3_IrqCtrl_Regs->ampctrl >> 28) > 0) {
114    /* IRQ Controller has support for multiple IRQ Controllers, each
115     * CPU can be routed to different Controllers, we find out which
116     * controller by looking at the IRQCTRL Select Register for this CPU.
117     * Each Controller is located at a 4KByte offset.
118     */
119    icsel = LEON3_IrqCtrl_Regs->icsel[LEON3_Cpu_Index/8];
120    icsel = (icsel >> ((7 - (LEON3_Cpu_Index & 0x7)) * 4)) & 0xf;
121    LEON3_IrqCtrl_Regs += icsel;
122  }
123  LEON3_IrqCtrl_Regs->mask[LEON3_Cpu_Index] = 0;
124  LEON3_IrqCtrl_Regs->force[LEON3_Cpu_Index] = 0;
125  LEON3_IrqCtrl_Regs->iclear = 0xffffffff;
126
127  /* Init Extended IRQ controller if available */
128  leon3_ext_irq_init();
129
130  /* If we are running without Driver Manager at startup, we must still
131   * assure that Timer and Console UART is working. So we can not
132   * depend on the DrvMgr capable Timer and Console UART drivers,
133   * instead we use the small-footprint drivers.
134   */
135#ifndef RTEMS_DRVMGR_STARTUP
136  /* find GP Timer */
137  adev = (void *)ambapp_for_each(&ambapp_plb, (OPTIONS_ALL|OPTIONS_APB_SLVS),
138                                 VENDOR_GAISLER, GAISLER_GPTIMER,
139                                 ambapp_find_by_idx, &leon3_timer_core_index);
140  if (adev) {
141    LEON3_Timer_Regs = (volatile struct gptimer_regs *)DEV_TO_APB(adev)->start;
142    timer_dev = adev;
143
144    /* Register AMBA Bus Frequency */
145    ambapp_freq_init(
146      &ambapp_plb,
147      timer_dev,
148      (LEON3_Timer_Regs->scaler_reload + 1)
149        * LEON3_GPTIMER_0_FREQUENCY_SET_BY_BOOT_LOADER
150    );
151    /* Set user prescaler configuration. Use this to increase accuracy of timer
152     * and accociated services like cpucounter.
153     * Note that minimum value is the number of timer instances present in
154     * GRTIMER/GPTIMER hardware. See HW manual.
155     */
156    if (leon3_timer_prescaler)
157      LEON3_Timer_Regs->scaler_reload = leon3_timer_prescaler;
158  }
159#else
160  /* Register Root bus, Use GRLIB AMBA PnP bus as root bus for LEON3 */
161  ambapp_grlib_root_register(&grlib_bus_config);
162#endif
163}
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