[PATCH 2/3] serial: 8250_early: prepare for dynamic BASE_BAUD
From: Vineet Gupta <hidden>
Date: 2014-12-24 07:12:35
Also in:
lkml
Subsystem:
the rest, tty layer and serial drivers · Maintainers:
Linus Torvalds, Greg Kroah-Hartman, Jiri Slaby
BASE_BAUD is pain in neck for multi-platform support as it hard codes at build time the clk value for early uart. Mitigate this by allowing arches/platforms to provide their own version which can do dynamic setup based on DT values etc (see next patch for usage) This was needed for ARC SDP platforms based on 2 different FPGA flows, each with a different UART clk value. Signed-off-by: Vineet Gupta <redacted> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <redacted> Cc: linux-serial@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: Rob Herring <robh@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> --- drivers/tty/serial/earlycon.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-)
diff --git a/drivers/tty/serial/earlycon.c b/drivers/tty/serial/earlycon.c
index 64fe25a4285c..bfd3537739e0 100644
--- a/drivers/tty/serial/earlycon.c
+++ b/drivers/tty/serial/earlycon.c@@ -54,6 +54,15 @@ static void __iomem * __init earlycon_map(unsigned long paddr, size_t size) return base; } +unsigned int __weak __init earlycon_base_baud(char *options) +{ +#ifdef BASE_BAUD + return BASE_BAUD; +#else + return 1843200/16; /* x86 early console */ +#endif +} + static int __init parse_options(struct earlycon_device *device, char *options) {
@@ -87,7 +96,7 @@ static int __init parse_options(struct earlycon_device *device, return -EINVAL; } - port->uartclk = BASE_BAUD * 16; + port->uartclk = earlycon_base_baud(options) * 16; options = strchr(options, ','); if (options) {
@@ -156,7 +165,7 @@ int __init of_setup_earlycon(unsigned long addr, port->iotype = UPIO_MEM; port->mapbase = addr; - port->uartclk = BASE_BAUD * 16; + port->uartclk = earlycon_base_baud(NULL) * 16; port->membase = earlycon_map(addr, SZ_4K); early_console_dev.con->data = &early_console_dev;
--
1.8.3.2