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authorLinus Torvalds <torvalds@linux-foundation.org>2015-04-21 19:33:10 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2015-04-21 19:33:10 +0300
commit41d5e08ea86af3359239d5a6f7021cdc61beaa49 (patch)
tree58ad584b29d097dfa3b5d7bc5e61370d676610a9 /drivers/tty/serial/earlycon.c
parent8d582b94291b40dbb5961f99172ee8ebfafd4c9c (diff)
parent5dbc32a88f1e73f244e6134fc119dd4d60a398c0 (diff)
downloadlinux-41d5e08ea86af3359239d5a6f7021cdc61beaa49.tar.xz
Merge tag 'tty-4.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty/serial updates from Greg KH: "Here's the big tty/serial driver update for 4.1-rc1. It was delayed for a bit due to some questions surrounding some of the console command line parsing changes that are in here. There's still one tiny regression for people who were previously putting multiple console command lines and expecting them all to be ignored for some odd reason, but Peter is working on fixing that. If not, I'll send a revert for the offending patch, but I have faith that Peter can address it. Other than the console work here, there's the usual serial driver updates and changes, and a buch of 8250 reworks to try to make that driver easier to maintain over time, and have it support more devices in the future. All of these have been in linux-next for a while" * tag 'tty-4.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (119 commits) n_gsm: Drop unneeded cast on netdev_priv sc16is7xx: expose RTS inversion in RS-485 mode serial: 8250_pci: port failed after wakeup from S3 earlycon: 8250: Document kernel command line options earlycon: 8250: Fix command line regression earlycon: Fix __earlycon_table stride tty: clean up the tty time logic a bit serial: 8250_dw: only get the clock rate in one place serial: 8250_dw: remove useless ACPI ID check dmaengine: hsu: move memory allocation to GFP_NOWAIT dmaengine: hsu: remove redundant pieces of code serial: 8250_pci: add Intel Tangier support dmaengine: hsu: add Intel Tangier PCI ID serial: 8250_pci: replace switch-case by formula for Intel MID serial: 8250_pci: replace switch-case by formula tty: cpm_uart: replace CONFIG_8xx by CONFIG_CPM1 serial: jsm: some off by one bugs serial: xuartps: Fix check in console_setup(). serial: xuartps: Get rid of register access macros. serial: xuartps: Fix iobase use. ...
Diffstat (limited to 'drivers/tty/serial/earlycon.c')
-rw-r--r--drivers/tty/serial/earlycon.c140
1 files changed, 95 insertions, 45 deletions
diff --git a/drivers/tty/serial/earlycon.c b/drivers/tty/serial/earlycon.c
index 64fe25a4285c..5fdc9f3ecd64 100644
--- a/drivers/tty/serial/earlycon.c
+++ b/drivers/tty/serial/earlycon.c
@@ -10,6 +10,9 @@
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
#include <linux/console.h>
#include <linux/kernel.h>
#include <linux/init.h>
@@ -34,6 +37,10 @@ static struct earlycon_device early_console_dev = {
.con = &early_con,
};
+extern struct earlycon_id __earlycon_table[];
+static const struct earlycon_id __earlycon_table_sentinel
+ __used __section(__earlycon_table_end);
+
static const struct of_device_id __earlycon_of_table_sentinel
__used __section(__earlycon_of_table_end);
@@ -54,44 +61,29 @@ static void __iomem * __init earlycon_map(unsigned long paddr, size_t size)
return base;
}
-static int __init parse_options(struct earlycon_device *device,
- char *options)
+static int __init parse_options(struct earlycon_device *device, char *options)
{
struct uart_port *port = &device->port;
- int mmio, mmio32, length;
+ int length;
unsigned long addr;
- if (!options)
- return -ENODEV;
+ if (uart_parse_earlycon(options, &port->iotype, &addr, &options))
+ return -EINVAL;
- mmio = !strncmp(options, "mmio,", 5);
- mmio32 = !strncmp(options, "mmio32,", 7);
- if (mmio || mmio32) {
- port->iotype = (mmio ? UPIO_MEM : UPIO_MEM32);
- options += mmio ? 5 : 7;
- addr = simple_strtoul(options, NULL, 0);
+ switch (port->iotype) {
+ case UPIO_MEM32:
+ port->regshift = 2; /* fall-through */
+ case UPIO_MEM:
port->mapbase = addr;
- if (mmio32)
- port->regshift = 2;
- } else if (!strncmp(options, "io,", 3)) {
- port->iotype = UPIO_PORT;
- options += 3;
- addr = simple_strtoul(options, NULL, 0);
+ break;
+ case UPIO_PORT:
port->iobase = addr;
- mmio = 0;
- } else if (!strncmp(options, "0x", 2)) {
- port->iotype = UPIO_MEM;
- addr = simple_strtoul(options, NULL, 0);
- port->mapbase = addr;
- } else {
+ break;
+ default:
return -EINVAL;
}
- port->uartclk = BASE_BAUD * 16;
-
- options = strchr(options, ',');
if (options) {
- options++;
device->baud = simple_strtoul(options, NULL, 0);
length = min(strcspn(options, " ") + 1,
(size_t)(sizeof(device->options)));
@@ -100,7 +92,7 @@ static int __init parse_options(struct earlycon_device *device,
if (port->iotype == UPIO_MEM || port->iotype == UPIO_MEM32)
pr_info("Early serial console at MMIO%s 0x%llx (options '%s')\n",
- mmio32 ? "32" : "",
+ (port->iotype == UPIO_MEM32) ? "32" : "",
(unsigned long long)port->mapbase,
device->options);
else
@@ -111,34 +103,21 @@ static int __init parse_options(struct earlycon_device *device,
return 0;
}
-int __init setup_earlycon(char *buf, const char *match,
- int (*setup)(struct earlycon_device *, const char *))
+static int __init register_earlycon(char *buf, const struct earlycon_id *match)
{
int err;
- size_t len;
struct uart_port *port = &early_console_dev.port;
- if (!buf || !match || !setup)
- return 0;
-
- len = strlen(match);
- if (strncmp(buf, match, len))
- return 0;
- if (buf[len] && (buf[len] != ','))
- return 0;
-
- buf += len + 1;
-
- err = parse_options(&early_console_dev, buf);
/* On parsing error, pass the options buf to the setup function */
- if (!err)
+ if (buf && !parse_options(&early_console_dev, buf))
buf = NULL;
+ port->uartclk = BASE_BAUD * 16;
if (port->mapbase)
port->membase = earlycon_map(port->mapbase, 64);
early_console_dev.con->data = &early_console_dev;
- err = setup(&early_console_dev, buf);
+ err = match->setup(&early_console_dev, buf);
if (err < 0)
return err;
if (!early_console_dev.con->write)
@@ -148,6 +127,77 @@ int __init setup_earlycon(char *buf, const char *match,
return 0;
}
+/**
+ * setup_earlycon - match and register earlycon console
+ * @buf: earlycon param string
+ *
+ * Registers the earlycon console matching the earlycon specified
+ * in the param string @buf. Acceptable param strings are of the form
+ * <name>,io|mmio|mmio32,<addr>,<options>
+ * <name>,0x<addr>,<options>
+ * <name>,<options>
+ * <name>
+ *
+ * Only for the third form does the earlycon setup() method receive the
+ * <options> string in the 'options' parameter; all other forms set
+ * the parameter to NULL.
+ *
+ * Returns 0 if an attempt to register the earlycon was made,
+ * otherwise negative error code
+ */
+int __init setup_earlycon(char *buf)
+{
+ const struct earlycon_id *match;
+
+ if (!buf || !buf[0])
+ return -EINVAL;
+
+ if (early_con.flags & CON_ENABLED)
+ return -EALREADY;
+
+ for (match = __earlycon_table; match->name[0]; match++) {
+ size_t len = strlen(match->name);
+
+ if (strncmp(buf, match->name, len))
+ continue;
+
+ if (buf[len]) {
+ if (buf[len] != ',')
+ continue;
+ buf += len + 1;
+ } else
+ buf = NULL;
+
+ return register_earlycon(buf, match);
+ }
+
+ return -ENOENT;
+}
+
+/* early_param wrapper for setup_earlycon() */
+static int __init param_setup_earlycon(char *buf)
+{
+ int err;
+
+ /*
+ * Just 'earlycon' is a valid param for devicetree earlycons;
+ * don't generate a warning from parse_early_params() in that case
+ */
+ if (!buf || !buf[0])
+ return 0;
+
+ err = setup_earlycon(buf);
+ if (err == -ENOENT) {
+ pr_warn("no match for %s\n", buf);
+ err = 0;
+ } else if (err == -EALREADY) {
+ pr_warn("already registered\n");
+ err = 0;
+ }
+ return err;
+}
+early_param("earlycon", param_setup_earlycon);
+
int __init of_setup_earlycon(unsigned long addr,
int (*setup)(struct earlycon_device *, const char *))
{