OpenE2K
/
linux
6
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

powerpc/powernv: Add support for direct mapped LPC on POWER9 

Use the new non-PCI ISA bridge support to expose the POWER9
LPC bus as direct mapped via the ISA IO port range. This
enables direct access via drivers such as 8250

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit is contained in:
Benjamin Herrenschmidt 2017-01-30 18:11:57 +11:00 committed by Michael Ellerman
parent b3c711a9e1
commit 023b13a501
2 changed files with 14 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
arch/powerpc/kernel/legacy_serial.c
View File

@ -233,7 +233,8 @@ static int __init add_legacy_isa_port(struct device_node *np,
*
* Note: Don't even try on P8 lpc, we know it's not directly mapped
*/
if (!of_device_is_compatible(isa_brg, "ibm,power8-lpc")) {
if (!of_device_is_compatible(isa_brg, "ibm,power8-lpc") ||
of_get_property(isa_brg, "ranges", NULL)) {
taddr = of_translate_address(np, reg);
if (taddr == OF_BAD_ADDR)
taddr = 0;

16
arch/powerpc/platforms/powernv/opal-lpc.c
View File

@ -407,9 +407,17 @@ void opal_lpc_init(void)
if (opal_lpc_chip_id < 0)
return;
/* Setup special IO ops */
ppc_pci_io = opal_lpc_io;
isa_io_special = true;
/* Does it support direct mapping ? */
if (of_get_property(np, "ranges", NULL)) {
pr_info("OPAL: Found memory mapped LPC bus on chip %d\n",
opal_lpc_chip_id);
isa_bridge_init_non_pci(np);
} else {
pr_info("OPAL: Found non-mapped LPC bus on chip %d\n",
opal_lpc_chip_id);
pr_info("OPAL: Power8 LPC bus found, chip ID %d\n", opal_lpc_chip_id);
/* Setup special IO ops */
ppc_pci_io = opal_lpc_io;
isa_io_special = true;
}
}