powerpc/4xx: Add optional "reset_type" property to control reboot via dts

By setting "reset_type" to one of the following values, the default
software reset mechanism may be overidden. Here the possible values of
"reset_type":

  1 - PPC4xx core reset
  2 - PPC4xx chip reset
  3 - PPC4xx system reset (default)

This will be used by a new PPC440SPe board port, which needs a "chip
reset" instead of the default "system reset" to be asserted.

Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
This commit is contained in:
Stefan Roese 2010-04-27 22:13:34 +00:00 committed by Josh Boyer
parent 101c192e11
commit a32fe93daf
2 changed files with 40 additions and 2 deletions

View File

@ -0,0 +1,18 @@
Reboot property to control system reboot on PPC4xx systems:
By setting "reset_type" to one of the following values, the default
software reset mechanism may be overidden. Here the possible values of
"reset_type":
1 - PPC4xx core reset
2 - PPC4xx chip reset
3 - PPC4xx system reset (default)
Example:
cpu@0 {
device_type = "cpu";
model = "PowerPC,440SPe";
...
reset-type = <2>; /* Use chip-reset */
};

View File

@ -191,11 +191,31 @@ static int __init ppc4xx_l2c_probe(void)
arch_initcall(ppc4xx_l2c_probe);
/*
* At present, this routine just applies a system reset.
* Apply a system reset. Alternatively a board specific value may be
* provided via the "reset-type" property in the cpu node.
*/
void ppc4xx_reset_system(char *cmd)
{
mtspr(SPRN_DBCR0, mfspr(SPRN_DBCR0) | DBCR0_RST_SYSTEM);
struct device_node *np;
u32 reset_type = DBCR0_RST_SYSTEM;
const u32 *prop;
np = of_find_node_by_type(NULL, "cpu");
if (np) {
prop = of_get_property(np, "reset-type", NULL);
/*
* Check if property exists and if it is in range:
* 1 - PPC4xx core reset
* 2 - PPC4xx chip reset
* 3 - PPC4xx system reset (default)
*/
if ((prop) && ((prop[0] >= 1) && (prop[0] <= 3)))
reset_type = prop[0] << 28;
}
mtspr(SPRN_DBCR0, mfspr(SPRN_DBCR0) | reset_type);
while (1)
; /* Just in case the reset doesn't work */
}