[PATCH v6 06/12] of: earlycon: Initialize port fields from DT properties
From: Peter Hurley <hidden>
Date: 2016-01-16 23:24:41
Also in:
lkml
Subsystem:
open firmware and flattened device tree, the rest, tty layer and serial drivers · Maintainers:
Rob Herring, Saravana Kannan, Linus Torvalds, Greg Kroah-Hartman, Jiri Slaby
Read the optional "reg-offset", "reg-shift", "reg-io-width" and endianness properties and initialize the respective struct uart_port field if found. NB: These bindings are common to several drivers and the values merely indicate the default value; the registering earlycon setup() method can simply override the values if required. Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Peter Hurley <redacted> --- drivers/of/fdt.c | 2 +- drivers/tty/serial/earlycon.c | 31 +++++++++++++++++++++++++++++++ include/linux/serial_core.h | 1 + 3 files changed, 33 insertions(+), 1 deletion(-)
diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index cfd3b35..e8fd54a 100644
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c@@ -839,7 +839,7 @@ static int __init early_init_dt_scan_chosen_serial(void) if (addr == OF_BAD_ADDR) return -ENXIO; - of_setup_earlycon(addr, match, options); + of_setup_earlycon(addr, match, offset, options); return 0; } return -ENODEV;
diff --git a/drivers/tty/serial/earlycon.c b/drivers/tty/serial/earlycon.c
index 7509ee34d..7089667 100644
--- a/drivers/tty/serial/earlycon.c
+++ b/drivers/tty/serial/earlycon.c@@ -19,6 +19,7 @@ #include <linux/io.h> #include <linux/serial_core.h> #include <linux/sizes.h> +#include <linux/of_fdt.h> #ifdef CONFIG_FIX_EARLYCON_MEM #include <asm/fixmap.h>
@@ -219,10 +220,13 @@ early_param("earlycon", param_setup_earlycon); int __init of_setup_earlycon(unsigned long addr, const struct earlycon_id *match, + unsigned long node, const char *options) { int err; struct uart_port *port = &early_console_dev.port; + const __be32 *val; + bool big_endian; spin_lock_init(&port->lock); port->iotype = UPIO_MEM;
@@ -230,6 +234,33 @@ int __init of_setup_earlycon(unsigned long addr, port->uartclk = BASE_BAUD * 16; port->membase = earlycon_map(addr, SZ_4K); + val = of_get_flat_dt_prop(node, "reg-offset", NULL); + if (val) + port->mapbase += be32_to_cpu(*val); + val = of_get_flat_dt_prop(node, "reg-shift", NULL); + if (val) + port->regshift = be32_to_cpu(*val); + big_endian = of_get_flat_dt_prop(node, "big-endian", NULL) != NULL || + (IS_ENABLED(CONFIG_CPU_BIG_ENDIAN) && + of_get_flat_dt_prop(node, "native-endian", NULL) != NULL); + val = of_get_flat_dt_prop(node, "reg-io-width", NULL); + if (val) { + switch (be32_to_cpu(*val)) { + case 1: + port->iotype = UPIO_MEM; + break; + case 2: + port->iotype = UPIO_MEM16; + break; + case 4: + port->iotype = (big_endian) ? UPIO_MEM32BE : UPIO_MEM32; + break; + default: + pr_warn("[%s] unsupported reg-io-width\n", match->name); + return -EINVAL; + } + } + if (options) { strlcpy(early_console_dev.options, options, sizeof(early_console_dev.options));
diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
index 62a4df0..6d1bed8 100644
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h@@ -360,6 +360,7 @@ extern const struct earlycon_id __earlycon_table_end[]; extern int setup_earlycon(char *buf); extern int of_setup_earlycon(unsigned long addr, const struct earlycon_id *match, + unsigned long node, const char *options); struct uart_port *uart_get_console(struct uart_port *ports, int nr,
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2.7.0