From 023b13a50183d9cfc4fc5a66cb1f773ace22024c Mon Sep 17 00:00:00 2001 From: Benjamin Herrenschmidt Date: Mon, 30 Jan 2017 18:11:57 +1100 Subject: [PATCH] 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 Signed-off-by: Michael Ellerman --- arch/powerpc/kernel/legacy_serial.c | 3 ++- arch/powerpc/platforms/powernv/opal-lpc.c | 18 +++++++++++++----- 2 files changed, 15 insertions(+), 6 deletions(-) diff --git a/arch/powerpc/kernel/legacy_serial.c b/arch/powerpc/kernel/legacy_serial.c index bc525ea..0694d20 100644 --- a/arch/powerpc/kernel/legacy_serial.c +++ b/arch/powerpc/kernel/legacy_serial.c @@ -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; diff --git a/arch/powerpc/platforms/powernv/opal-lpc.c b/arch/powerpc/platforms/powernv/opal-lpc.c index 2048ce7..1a8cd54 100644 --- a/arch/powerpc/platforms/powernv/opal-lpc.c +++ b/arch/powerpc/platforms/powernv/opal-lpc.c @@ -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; - - pr_info("OPAL: Power8 LPC bus found, chip ID %d\n", opal_lpc_chip_id); + /* 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); + + /* Setup special IO ops */ + ppc_pci_io = opal_lpc_io; + isa_io_special = true; + } } -- 2.7.4