/*
* AMBA Plug & Play Bus Driver
*
* This driver hook performs bus scanning.
*
* COPYRIGHT (c) 2011.
* Aeroflex Gaisler
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://www.rtems.org/license/LICENSE.
*/
#include <bsp.h>
#include <bsp/fatal.h>
#include <leon.h>
#include <grlib/ambapp.h>
#include <rtems/sysinit.h>
unsigned int leon3_timer_prescaler __attribute__((weak)) = 0;
int leon3_timer_core_index __attribute__((weak)) = 0;
/* AMBA Plug&Play information description.
*
* After software has scanned AMBA PnP it builds a tree to make
* it easier for drivers to work with the bus architecture.
*/
struct ambapp_bus ambapp_plb;
/* If RTEMS_DRVMGR_STARTUP is defined extra code is added that
* registers the GRLIB AMBA PnP bus driver as root driver.
*/
#ifdef RTEMS_DRVMGR_STARTUP
#include <drvmgr/drvmgr.h>
#include <grlib/ambapp_bus_grlib.h>
/* Driver resources configuration for AMBA root bus. It is declared weak
* so that the user may override it, if the defualt settings are not
* enough.
*/
struct drvmgr_bus_res grlib_drv_resources __attribute__((weak)) =
{
.next = NULL,
.resource =
{
DRVMGR_RES_EMPTY,
}
};
/* GRLIB AMBA bus configuration (the LEON3 root bus configuration) */
struct grlib_config grlib_bus_config =
{
&ambapp_plb, /* AMBAPP bus setup */
&grlib_drv_resources, /* Driver configuration */
};
#endif
rtems_interrupt_lock LEON3_IrqCtrl_Lock =
RTEMS_INTERRUPT_LOCK_INITIALIZER("LEON3 IrqCtrl");
/* Pointers to Interrupt Controller configuration registers */
volatile struct irqmp_regs *LEON3_IrqCtrl_Regs;
struct ambapp_dev *LEON3_IrqCtrl_Adev;
volatile struct gptimer_regs *LEON3_Timer_Regs;
struct ambapp_dev *LEON3_Timer_Adev;
/*
* amba_initialize
*
* Must be called just before drivers are initialized.
* Used to scan system bus. Probes for AHB masters, AHB slaves and
* APB slaves. Addresses to configuration areas of the AHB masters,
* AHB slaves, APB slaves and APB master are storeds in
* amba_ahb_masters, amba_ahb_slaves and amba.
*/
static void amba_initialize(void)
{
int icsel;
struct ambapp_dev *adev;
/* Scan AMBA Plug&Play read-only information. The routine builds a PnP
* tree into ambapp_plb in RAM, after this we never access the PnP
* information in hardware directly any more.
* Since on Processor Local Bus (PLB) memory mapping is 1:1
*/
ambapp_scan(&ambapp_plb, LEON3_IO_AREA, NULL, NULL);
/* Find LEON3 Interrupt controller */
adev = (void *)ambapp_for_each(&ambapp_plb, (OPTIONS_ALL|OPTIONS_APB_SLVS),
VENDOR_GAISLER, GAISLER_IRQMP,
ambapp_find_by_idx, NULL);
if (adev == NULL) {
/* PANIC IRQ controller not found!
*
* What else can we do but stop ...
*/
bsp_fatal(LEON3_FATAL_NO_IRQMP_CONTROLLER);
}
LEON3_IrqCtrl_Regs = (volatile struct irqmp_regs *)DEV_TO_APB(adev)->start;
LEON3_IrqCtrl_Adev = adev;
if ((LEON3_IrqCtrl_Regs->ampctrl >> 28) > 0) {
/* IRQ Controller has support for multiple IRQ Controllers, each
* CPU can be routed to different Controllers, we find out which
* controller by looking at the IRQCTRL Select Register for this CPU.
* Each Controller is located at a 4KByte offset.
*/
icsel = LEON3_IrqCtrl_Regs->icsel[LEON3_Cpu_Index/8];
icsel = (icsel >> ((7 - (LEON3_Cpu_Index & 0x7)) * 4)) & 0xf;
LEON3_IrqCtrl_Regs += icsel;
}
LEON3_IrqCtrl_Regs->mask[LEON3_Cpu_Index] = 0;
LEON3_IrqCtrl_Regs->force[LEON3_Cpu_Index] = 0;
LEON3_IrqCtrl_Regs->iclear = 0xffffffff;
/* Init Extended IRQ controller if available */
leon3_ext_irq_init();
/* find GP Timer */
adev = (void *)ambapp_for_each(&ambapp_plb, (OPTIONS_ALL|OPTIONS_APB_SLVS),
VENDOR_GAISLER, GAISLER_GPTIMER,
ambapp_find_by_idx, &leon3_timer_core_index);
if (adev) {
LEON3_Timer_Regs = (volatile struct gptimer_regs *)DEV_TO_APB(adev)->start;
LEON3_Timer_Adev = adev;
/* Register AMBA Bus Frequency */
ambapp_freq_init(
&ambapp_plb,
LEON3_Timer_Adev,
(LEON3_Timer_Regs->scaler_reload + 1)
* LEON3_GPTIMER_0_FREQUENCY_SET_BY_BOOT_LOADER
);
/* Set user prescaler configuration. Use this to increase accuracy of timer
* and accociated services like cpucounter.
* Note that minimum value is the number of timer instances present in
* GRTIMER/GPTIMER hardware. See HW manual.
*/
if (leon3_timer_prescaler)
LEON3_Timer_Regs->scaler_reload = leon3_timer_prescaler;
}
#ifdef RTEMS_DRVMGR_STARTUP
/* Register Root bus, Use GRLIB AMBA PnP bus as root bus for LEON3 */
ambapp_grlib_root_register(&grlib_bus_config);
#endif
}
RTEMS_SYSINIT_ITEM(
amba_initialize,
RTEMS_SYSINIT_BSP_START,
RTEMS_SYSINIT_ORDER_SECOND
);
