// SPDX-License-Identifier: GPL-2.0+
/*
* (C) Copyright 2000-2002
* Wolfgang Denk, DENX Software Engineering, wd@denx.de.
*/
#include <common.h>
#include <mpc8xx.h>
#include <mpc8xx_irq.h>
#include <asm/cpm_8xx.h>
#include <asm/processor.h>
#include <asm/io.h>
/************************************************************************/
/*
* CPM interrupt vector functions.
*/
struct interrupt_action {
interrupt_handler_t *handler;
void *arg;
};
static struct interrupt_action cpm_vecs[CPMVEC_NR];
static struct interrupt_action irq_vecs[NR_IRQS];
static void cpm_interrupt_init(void);
static void cpm_interrupt(void *regs);
/************************************************************************/
void interrupt_init_cpu(unsigned *decrementer_count)
{
immap_t __iomem *immr = (immap_t __iomem *)CONFIG_SYS_IMMR;
*decrementer_count = get_tbclk() / CONFIG_SYS_HZ;
/* disable all interrupts */
out_be32(&immr->im_siu_conf.sc_simask, 0);
/* Configure CPM interrupts */
cpm_interrupt_init();
}
/************************************************************************/
/*
* Handle external interrupts
*/
void external_interrupt(struct pt_regs *regs)
{
immap_t __iomem *immr = (immap_t __iomem *)CONFIG_SYS_IMMR;
int irq;
ulong simask;
ulong vec, v_bit;
/*
* read the SIVEC register and shift the bits down
* to get the irq number
*/
vec = in_be32(&immr->im_siu_conf.sc_sivec);
irq = vec >> 26;
v_bit = 0x80000000UL >> irq;
/*
* Read Interrupt Mask Register and Mask Interrupts
*/
simask = in_be32(&immr->im_siu_conf.sc_simask);
clrbits_be32(&immr->im_siu_conf.sc_simask, 0xFFFF0000 >> irq);
if (!(irq & 0x1)) { /* External Interrupt ? */
ulong siel;
/*
* Read Interrupt Edge/Level Register
*/
siel = in_be32(&immr->im_siu_conf.sc_siel);
if (siel & v_bit) { /* edge triggered interrupt ? */
/*
* Rewrite SIPEND Register to clear interrupt
*/
out_be32(&immr->im_siu_conf.sc_sipend, v_bit);
}
}
if (irq_vecs[irq].handler != NULL) {
irq_vecs[irq].handler(irq_vecs[irq].arg);
} else {
printf("\nBogus External Interrupt IRQ %d Vector %ld\n",
irq, vec);
/* turn off the bogus interrupt to avoid it from now */
simask &= ~v_bit;
}
/*
* Re-Enable old Interrupt Mask
*/
out_be32(&immr->im_siu_conf.sc_simask, simask);
}
/************************************************************************/
/*
* CPM interrupt handler
*/
static void cpm_interrupt(void *regs)
{
immap_t __iomem *immr = (immap_t __iomem *)CONFIG_SYS_IMMR;
uint vec;
/*
* Get the vector by setting the ACK bit
* and then reading the register.
*/
out_be16(&immr->im_cpic.cpic_civr, 1);
vec = in_be16(&immr->im_cpic.cpic_civr);
vec >>= 11;
if (cpm_vecs[vec].handler != NULL) {
(*cpm_vecs[vec].handler) (cpm_vecs[vec].arg);
} else {
clrbits_be32(&immr->im_cpic.cpic_cimr, 1 << vec);
printf("Masking bogus CPM interrupt vector 0x%x\n", vec);
}
/*
* After servicing the interrupt,
* we have to remove the status indicator.
*/
setbits_be32(&immr->im_cpic.cpic_cisr, 1 << vec);
}
/*
* The CPM can generate the error interrupt when there is a race
* condition between generating and masking interrupts. All we have
* to do is ACK it and return. This is a no-op function so we don't
* need any special tests in the interrupt handler.
*/
static void cpm_error_interrupt(void *dummy)
{
}
/************************************************************************/
/*
* Install and free an interrupt handler
*/
void irq_install_handler(int vec, interrupt_handler_t *handler, void *arg)
{
immap_t __iomem *immr = (immap_t __iomem *)CONFIG_SYS_IMMR;
if ((vec & CPMVEC_OFFSET) != 0) {
/* CPM interrupt */
vec &= 0xffff;
if (cpm_vecs[vec].handler != NULL)
printf("CPM interrupt 0x%x replacing 0x%x\n",
(uint)handler, (uint)cpm_vecs[vec].handler);
cpm_vecs[vec].handler = handler;
cpm_vecs[vec].arg = arg;
setbits_be32(&immr->im_cpic.cpic_cimr, 1 << vec);
} else {
/* SIU interrupt */
if (irq_vecs[vec].handler != NULL)
printf("SIU interrupt %d 0x%x replacing 0x%x\n",
vec, (uint)handler, (uint)cpm_vecs[vec].handler);
irq_vecs[vec].handler = handler;
irq_vecs[vec].arg = arg;
setbits_be32(&immr->im_siu_conf.sc_simask, 1 << (31 - vec));
}
}
void irq_free_handler(int vec)
{
immap_t __iomem *immr = (immap_t __iomem *)CONFIG_SYS_IMMR;
if ((vec & CPMVEC_OFFSET) != 0) {
/* CPM interrupt */
vec &= 0xffff;
clrbits_be32(&immr->im_cpic.cpic_cimr, 1 << vec);
cpm_vecs[vec].handler = NULL;
cpm_vecs[vec].arg = NULL;
} else {
/* SIU interrupt */
clrbits_be32(&immr->im_siu_conf.sc_simask, 1 << (31 - vec));
irq_vecs[vec].handler = NULL;
irq_vecs[vec].arg = NULL;
}
}
/************************************************************************/
static void cpm_interrupt_init(void)
{
immap_t __iomem *immr = (immap_t __iomem *)CONFIG_SYS_IMMR;
uint cicr;
/*
* Initialize the CPM interrupt controller.
*/
cicr = CICR_SCD_SCC4 | CICR_SCC_SCC3 | CICR_SCB_SCC2 | CICR_SCA_SCC1 |
((CPM_INTERRUPT / 2) << 13) | CICR_HP_MASK;
out_be32(&immr->im_cpic.cpic_cicr, cicr);
out_be32(&immr->im_cpic.cpic_cimr, 0);
/*
* Install the error handler.
*/
irq_install_handler(CPMVEC_ERROR, cpm_error_interrupt, NULL);
setbits_be32(&immr->im_cpic.cpic_cicr, CICR_IEN);
/*
* Install the cpm interrupt handler
*/
irq_install_handler(CPM_INTERRUPT, cpm_interrupt, NULL);
}
/************************************************************************/
/*
* timer_interrupt - gets called when the decrementer overflows,
* with interrupts disabled.
* Trivial implementation - no need to be really accurate.
*/
void timer_interrupt_cpu(struct pt_regs *regs)
{
immap_t __iomem *immr = (immap_t __iomem *)CONFIG_SYS_IMMR;
/* Reset Timer Expired and Timers Interrupt Status */
out_be32(&immr->im_clkrstk.cark_plprcrk, KAPWR_KEY);
__asm__ ("nop");
/*
Clear TEXPS (and TMIST on older chips). SPLSS (on older
chips) is cleared too.
Bitwise OR is a read-modify-write operation so ALL bits
which are cleared by writing `1' would be cleared by
operations like
immr->im_clkrst.car_plprcr |= PLPRCR_TEXPS;
The same can be achieved by simple writing of the PLPRCR
to itself. If a bit value should be preserved, read the
register, ZERO the bit and write, not OR, the result back.
*/
setbits_be32(&immr->im_clkrst.car_plprcr, 0);
}
/************************************************************************/