random-mirrors/smaeul-u-boot
1
0
Fork 0
mirror of https://github.com/smaeul/u-boot.git synced 2025-10-31 03:58:17 +00:00
Code Issues Packages Projects Releases Wiki Activity
smaeul-u-boot/arch/powerpc/cpu/mpc5xxx/interrupts.c
Wolfgang Denk 54841ab50c Make sure that argv[] argument pointers are not modified. 
The hush shell dynamically allocates (and re-allocates) memory for the
argument strings in the "char *argv[]" argument vector passed to
commands.  Any code that modifies these pointers will cause serious
corruption of the malloc data structures and crash U-Boot, so make
sure the compiler can check that no such modifications are being done
by changing the code into "char * const argv[]".

This modification is the result of debugging a strange crash caused
after adding a new command, which used the following argument
processing code which has been working perfectly fine in all Unix
systems since version 6 - but not so in U-Boot:

int main (int argc, char **argv)
{
	while (--argc > 0 && **++argv == '-') {
/* ====> */	while (*++*argv) {
			switch (**argv) {
			case 'd':
				debug++;
				break;
			...
			default:
				usage ();
			}
		}
	}
	...
}

The line marked "====>" will corrupt the malloc data structures and
usually cause U-Boot to crash when the next command gets executed by
the shell.  With the modification, the compiler will prevent this with
an
	error: increment of read-only location '*argv'

N.B.: The code above can be trivially rewritten like this:

	while (--argc > 0 && **++argv == '-') {
		char *arg = *argv;
		while (*++arg) {
			switch (*arg) {
			...

Signed-off-by: Wolfgang Denk <wd@denx.de>
Acked-by: Mike Frysinger <vapier@gentoo.org>
2010-07-04 23:55:42 +02:00

347 lines
8.7 KiB
C
Raw Blame History

/*
* (C) Copyright 2006
* Detlev Zundel, DENX Software Engineering, dzu@denx.de
*
* (C) Copyright -2003
* Wolfgang Denk, DENX Software Engineering, wd@denx.de.
*
* (C) Copyright 2001
* Josh Huber <huber@mclx.com>, Mission Critical Linux, Inc.
*
* See file CREDITS for list of people who contributed to this
* project.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*/
/* this section was ripped out of arch/powerpc/syslib/mpc52xx_pic.c in the
* Linux 2.6 source with the following copyright.
*
* Based on (well, mostly copied from) the code from the 2.4 kernel by
* Dale Farnsworth <dfarnsworth@mvista.com> and Kent Borg.
*
* Copyright (C) 2004 Sylvain Munaut <tnt@246tNt.com>
* Copyright (C) 2003 Montavista Software, Inc
*/
#include <common.h>
#include <asm/processor.h>
#include <asm/io.h>
#include <command.h>
struct irq_action {
interrupt_handler_t *handler;
void *arg;
ulong count;
};
static struct irq_action irq_handlers[NR_IRQS];
static struct mpc5xxx_intr *intr;
static struct mpc5xxx_sdma *sdma;
static void mpc5xxx_ic_disable(unsigned int irq)
{
u32 val;
if (irq == MPC5XXX_IRQ0) {
val = in_be32(&intr->ctrl);
val &= ~(1 << 11);
out_be32(&intr->ctrl, val);
} else if (irq < MPC5XXX_IRQ1) {
BUG();
} else if (irq <= MPC5XXX_IRQ3) {
val = in_be32(&intr->ctrl);
val &= ~(1 << (10 - (irq - MPC5XXX_IRQ1)));
out_be32(&intr->ctrl, val);
} else if (irq < MPC5XXX_SDMA_IRQ_BASE) {
val = in_be32(&intr->main_mask);
val |= 1 << (16 - (irq - MPC5XXX_MAIN_IRQ_BASE));
out_be32(&intr->main_mask, val);
} else if (irq < MPC5XXX_PERP_IRQ_BASE) {
val = in_be32(&sdma->IntMask);
val |= 1 << (irq - MPC5XXX_SDMA_IRQ_BASE);
out_be32(&sdma->IntMask, val);
} else {
val = in_be32(&intr->per_mask);
val |= 1 << (31 - (irq - MPC5XXX_PERP_IRQ_BASE));
out_be32(&intr->per_mask, val);
}
}
static void mpc5xxx_ic_enable(unsigned int irq)
{
u32 val;
if (irq == MPC5XXX_IRQ0) {
val = in_be32(&intr->ctrl);
val |= 1 << 11;
out_be32(&intr->ctrl, val);
} else if (irq < MPC5XXX_IRQ1) {
BUG();
} else if (irq <= MPC5XXX_IRQ3) {
val = in_be32(&intr->ctrl);
val |= 1 << (10 - (irq - MPC5XXX_IRQ1));
out_be32(&intr->ctrl, val);
} else if (irq < MPC5XXX_SDMA_IRQ_BASE) {
val = in_be32(&intr->main_mask);
val &= ~(1 << (16 - (irq - MPC5XXX_MAIN_IRQ_BASE)));
out_be32(&intr->main_mask, val);
} else if (irq < MPC5XXX_PERP_IRQ_BASE) {
val = in_be32(&sdma->IntMask);
val &= ~(1 << (irq - MPC5XXX_SDMA_IRQ_BASE));
out_be32(&sdma->IntMask, val);
} else {
val = in_be32(&intr->per_mask);
val &= ~(1 << (31 - (irq - MPC5XXX_PERP_IRQ_BASE)));
out_be32(&intr->per_mask, val);
}
}
static void mpc5xxx_ic_ack(unsigned int irq)
{
u32 val;
/*
* Only some irqs are reset here, others in interrupting hardware.
*/
switch (irq) {
case MPC5XXX_IRQ0:
val = in_be32(&intr->ctrl);
val |= 0x08000000;
out_be32(&intr->ctrl, val);
break;
case MPC5XXX_CCS_IRQ:
val = in_be32(&intr->enc_status);
val |= 0x00000400;
out_be32(&intr->enc_status, val);
break;
case MPC5XXX_IRQ1:
val = in_be32(&intr->ctrl);
val |= 0x04000000;
out_be32(&intr->ctrl, val);
break;
case MPC5XXX_IRQ2:
val = in_be32(&intr->ctrl);
val |= 0x02000000;
out_be32(&intr->ctrl, val);
break;
case MPC5XXX_IRQ3:
val = in_be32(&intr->ctrl);
val |= 0x01000000;
out_be32(&intr->ctrl, val);
break;
default:
if (irq >= MPC5XXX_SDMA_IRQ_BASE
&& irq < (MPC5XXX_SDMA_IRQ_BASE + MPC5XXX_SDMA_IRQ_NUM)) {
out_be32(&sdma->IntPend,
1 << (irq - MPC5XXX_SDMA_IRQ_BASE));
}
break;
}
}
static void mpc5xxx_ic_disable_and_ack(unsigned int irq)
{
mpc5xxx_ic_disable(irq);
mpc5xxx_ic_ack(irq);
}
static void mpc5xxx_ic_end(unsigned int irq)
{
mpc5xxx_ic_enable(irq);
}
void mpc5xxx_init_irq(void)
{
u32 intr_ctrl;
/* Remap the necessary zones */
intr = (struct mpc5xxx_intr *)(MPC5XXX_ICTL);
sdma = (struct mpc5xxx_sdma *)(MPC5XXX_SDMA);
/* Disable all interrupt sources. */
out_be32(&sdma->IntPend, 0xffffffff); /* 1 means clear pending */
out_be32(&sdma->IntMask, 0xffffffff); /* 1 means disabled */
out_be32(&intr->per_mask, 0x7ffffc00); /* 1 means disabled */
out_be32(&intr->main_mask, 0x00010fff); /* 1 means disabled */
intr_ctrl = in_be32(&intr->ctrl);
intr_ctrl |= 0x0f000000 | /* clear IRQ 0-3 */
0x00ff0000 | /* IRQ 0-3 level sensitive low active */
0x00001000 | /* MEE master external enable */
0x00000000 | /* 0 means disable IRQ 0-3 */
0x00000001; /* CEb route critical normally */
out_be32(&intr->ctrl, intr_ctrl);
/* Zero a bunch of the priority settings. */
out_be32(&intr->per_pri1, 0);
out_be32(&intr->per_pri2, 0);
out_be32(&intr->per_pri3, 0);
out_be32(&intr->main_pri1, 0);
out_be32(&intr->main_pri2, 0);
}
int mpc5xxx_get_irq(struct pt_regs *regs)
{
u32 status;
int irq = -1;
status = in_be32(&intr->enc_status);
if (status & 0x00000400) { /* critical */
irq = (status >> 8) & 0x3;
if (irq == 2) /* high priority peripheral */
goto peripheral;
irq += MPC5XXX_CRIT_IRQ_BASE;
} else if (status & 0x00200000) { /* main */
irq = (status >> 16) & 0x1f;
if (irq == 4) /* low priority peripheral */
goto peripheral;
irq += MPC5XXX_MAIN_IRQ_BASE;
} else if (status & 0x20000000) { /* peripheral */
peripheral:
irq = (status >> 24) & 0x1f;
if (irq == 0) { /* bestcomm */
status = in_be32(&sdma->IntPend);
irq = ffs(status) + MPC5XXX_SDMA_IRQ_BASE - 1;
} else
irq += MPC5XXX_PERP_IRQ_BASE;
}
return irq;
}
/****************************************************************************/
int interrupt_init_cpu(ulong * decrementer_count)
{
*decrementer_count = get_tbclk() / CONFIG_SYS_HZ;
mpc5xxx_init_irq();
return (0);
}
/****************************************************************************/
/*
* Handle external interrupts
*/
void external_interrupt(struct pt_regs *regs)
{
int irq, unmask = 1;
irq = mpc5xxx_get_irq(regs);
mpc5xxx_ic_disable_and_ack(irq);
enable_interrupts();
if (irq_handlers[irq].handler != NULL)
(*irq_handlers[irq].handler) (irq_handlers[irq].arg);
else {
printf("\nBogus External Interrupt IRQ %d\n", irq);
/*
* turn off the bogus interrupt, otherwise it
* might repeat forever
*/
unmask = 0;
}
if (unmask)
mpc5xxx_ic_end(irq);
}
void timer_interrupt_cpu(struct pt_regs *regs)
{
/* nothing to do here */
return;
}
/****************************************************************************/
/*
* Install and free a interrupt handler.
*/
void irq_install_handler(int irq, interrupt_handler_t * handler, void *arg)
{
if (irq < 0 || irq >= NR_IRQS) {
printf("irq_install_handler: bad irq number %d\n", irq);
return;
}
if (irq_handlers[irq].handler != NULL)
printf("irq_install_handler: 0x%08lx replacing 0x%08lx\n",
(ulong) handler, (ulong) irq_handlers[irq].handler);
irq_handlers[irq].handler = handler;
irq_handlers[irq].arg = arg;
mpc5xxx_ic_enable(irq);
}
void irq_free_handler(int irq)
{
if (irq < 0 || irq >= NR_IRQS) {
printf("irq_free_handler: bad irq number %d\n", irq);
return;
}
mpc5xxx_ic_disable(irq);
irq_handlers[irq].handler = NULL;
irq_handlers[irq].arg = NULL;
}
/****************************************************************************/
#if defined(CONFIG_CMD_IRQ)
void do_irqinfo(cmd_tbl_t * cmdtp, bd_t * bd, int flag, int argc, char * const argv[])
{
int irq, re_enable;
u32 intr_ctrl;
char *irq_config[] = { "level sensitive, active high",
"edge sensitive, rising active edge",
"edge sensitive, falling active edge",
"level sensitive, active low"
};
re_enable = disable_interrupts();
intr_ctrl = in_be32(&intr->ctrl);
printf("Interrupt configuration:\n");
for (irq = 0; irq <= 3; irq++) {
printf("IRQ%d: %s\n", irq,
irq_config[(intr_ctrl >> (22 - 2 * irq)) & 0x3]);
}
puts("\nInterrupt-Information:\n" "Nr Routine Arg Count\n");
for (irq = 0; irq < NR_IRQS; irq++)
if (irq_handlers[irq].handler != NULL)
printf("%02d %08lx %08lx %ld\n", irq,
(ulong) irq_handlers[irq].handler,
(ulong) irq_handlers[irq].arg,
irq_handlers[irq].count);
if (re_enable)
enable_interrupts();
}
#endif
Reference in New Issue View Git Blame Copy Permalink