* [PATCH 1/4] of: Create of_console_check() for selecting a console specified in /chosen
2014-06-18 20:54 [PATCH 0/4] of Automatic console registration cleanups Grant Likely
@ 2014-06-18 20:54 ` Grant Likely
2014-06-18 20:54 ` [PATCH 2/4] of: Enable console on serial ports specified by /chosen/stdout-path Grant Likely
` (2 subsequent siblings)
3 siblings, 0 replies; 5+ messages in thread
From: Grant Likely @ 2014-06-18 20:54 UTC (permalink / raw)
To: linux-kernel, devicetree, robh, olof, benh; +Cc: Grant Likely
The devicetree has a binding for specifying the console device in the
/chosen node, but the kernel doesn't use it consistently. This change
adds an API for testing if a device node is a console, and adds a
preferred console entry if it is.
At the same time this patch removes the of_device_is_stdout_path() API
since it is unused.
Signed-off-by: Grant Likely <grant.likely@linaro.org>
Tested-by: Sascha Hauer <s.hauer@pengutronix.de>
---
drivers/of/base.c | 23 +++++++++++++----------
include/linux/of.h | 6 +++---
2 files changed, 16 insertions(+), 13 deletions(-)
diff --git a/drivers/of/base.c b/drivers/of/base.c
index 8368d96ae7b4..ed037ae7eefe 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -17,6 +17,7 @@
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
+#include <linux/console.h>
#include <linux/ctype.h>
#include <linux/cpu.h>
#include <linux/module.h>
@@ -2179,20 +2180,22 @@ const char *of_prop_next_string(struct property *prop, const char *cur)
EXPORT_SYMBOL_GPL(of_prop_next_string);
/**
- * of_device_is_stdout_path - check if a device node matches the
- * linux,stdout-path property
- *
- * Check if this device node matches the linux,stdout-path property
- * in the chosen node. return true if yes, false otherwise.
+ * of_console_check() - Test and setup console for DT setup
+ * @dn - Pointer to device node
+ * @name - Name to use for preferred console without index. ex. "ttyS"
+ * @index - Index to use for preferred console.
+ *
+ * Check if the given device node matches the stdout-path property in the
+ * /chosen node. If it does then register it as the preferred console and return
+ * TRUE. Otherwise return FALSE.
*/
-int of_device_is_stdout_path(struct device_node *dn)
+bool of_console_check(struct device_node *dn, char *name, int index)
{
- if (!of_stdout)
+ if (!dn || dn != of_stdout || console_set_on_cmdline)
return false;
-
- return of_stdout == dn;
+ return add_preferred_console(name, index, NULL);
}
-EXPORT_SYMBOL_GPL(of_device_is_stdout_path);
+EXPORT_SYMBOL_GPL(of_console_check);
/**
* of_find_next_cache_node - Find a node's subsidiary cache
diff --git a/include/linux/of.h b/include/linux/of.h
index 196b34c1ef4e..9d9734056e39 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -352,7 +352,7 @@ const __be32 *of_prop_next_u32(struct property *prop, const __be32 *cur,
*/
const char *of_prop_next_string(struct property *prop, const char *cur);
-int of_device_is_stdout_path(struct device_node *dn);
+bool of_console_check(struct device_node *dn, char *name, int index);
#else /* CONFIG_OF */
@@ -564,9 +564,9 @@ static inline int of_machine_is_compatible(const char *compat)
return 0;
}
-static inline int of_device_is_stdout_path(struct device_node *dn)
+static inline bool of_console_check(const struct device_node *dn, const char *name, int index)
{
- return 0;
+ return false;
}
static inline const __be32 *of_prop_next_u32(struct property *prop,
--
1.9.1
^ permalink raw reply related [flat|nested] 5+ messages in thread* [PATCH 2/4] of: Enable console on serial ports specified by /chosen/stdout-path
2014-06-18 20:54 [PATCH 0/4] of Automatic console registration cleanups Grant Likely
2014-06-18 20:54 ` [PATCH 1/4] of: Create of_console_check() for selecting a console specified in /chosen Grant Likely
@ 2014-06-18 20:54 ` Grant Likely
2014-06-18 20:54 ` [PATCH 3/4] arm/versatile: Add the uart as the stdout device Grant Likely
2014-06-18 20:54 ` [PATCH 4/4] tty: Update hypervisor tty drivers to use core stdout parsing code Grant Likely
3 siblings, 0 replies; 5+ messages in thread
From: Grant Likely @ 2014-06-18 20:54 UTC (permalink / raw)
To: linux-kernel, devicetree, robh, olof, benh; +Cc: Grant Likely
If the devicetree specifies a serial port as a stdout device, then the
kernel can use it as the default console if nothing else was selected on
the command line. For any serial port that uses the uart_add_one_port()
feature, the uart_add_one_port() has all the information needed to
automatically enable the console device, which is what this patch does.
With this change applied, a device tree platform can be booted without
any console= parameters on the command line and the kernel will still be
able to determine its console.
Tested on QEMU Versatile model and i.MX
Signed-off-by: Grant Likely <grant.likely@linaro.org>
Tested-by: Sascha Hauer <s.hauer@pengutronix.de>
---
drivers/tty/serial/serial_core.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c
index fbf6c5ad222f..3ce68f962c92 100644
--- a/drivers/tty/serial/serial_core.c
+++ b/drivers/tty/serial/serial_core.c
@@ -26,6 +26,7 @@
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/console.h>
+#include <linux/of.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/device.h>
@@ -2615,6 +2616,8 @@ int uart_add_one_port(struct uart_driver *drv, struct uart_port *uport)
spin_lock_init(&uport->lock);
lockdep_set_class(&uport->lock, &port_lock_key);
}
+ if (uport->cons && uport->dev)
+ of_console_check(uport->dev->of_node, uport->cons->name, uport->line);
uart_configure_port(drv, state, uport);
--
1.9.1
^ permalink raw reply related [flat|nested] 5+ messages in thread
* [PATCH 4/4] tty: Update hypervisor tty drivers to use core stdout parsing code.
2014-06-18 20:54 [PATCH 0/4] of Automatic console registration cleanups Grant Likely
` (2 preceding siblings ...)
2014-06-18 20:54 ` [PATCH 3/4] arm/versatile: Add the uart as the stdout device Grant Likely
@ 2014-06-18 20:54 ` Grant Likely
3 siblings, 0 replies; 5+ messages in thread
From: Grant Likely @ 2014-06-18 20:54 UTC (permalink / raw)
To: linux-kernel, devicetree, robh, olof, benh; +Cc: Grant Likely
The evh_bytechan, hvc_opal and hvc_vio drivers all open code the parsing
of the stdout node in the device tree. This patch simplifies the driver
by removing the duplicated functionality.
Signed-off-by: Grant Likely <grant.likely@linaro.org>
---
drivers/of/base.c | 5 ++++-
drivers/tty/ehv_bytechan.c | 43 ++++---------------------------------------
drivers/tty/hvc/hvc_opal.c | 15 +++------------
drivers/tty/hvc/hvc_vio.c | 29 ++++++++++-------------------
include/linux/of.h | 1 +
5 files changed, 22 insertions(+), 71 deletions(-)
diff --git a/drivers/of/base.c b/drivers/of/base.c
index ed037ae7eefe..af3d8722064a 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -36,7 +36,7 @@ struct device_node *of_allnodes;
EXPORT_SYMBOL(of_allnodes);
struct device_node *of_chosen;
struct device_node *of_aliases;
-static struct device_node *of_stdout;
+struct device_node *of_stdout;
static struct kset *of_kset;
@@ -2062,9 +2062,12 @@ void of_alias_scan(void * (*dt_alloc)(u64 size, u64 align))
of_chosen = of_find_node_by_path("/chosen@0");
if (of_chosen) {
+ /* linux,stdout-path and /aliases/stdout are for legacy compatibility */
const char *name = of_get_property(of_chosen, "stdout-path", NULL);
if (!name)
name = of_get_property(of_chosen, "linux,stdout-path", NULL);
+ if (IS_ENABLED(CONFIG_PPC) && !name)
+ name = of_get_property(of_aliases, "stdout", NULL);
if (name)
of_stdout = of_find_node_by_path(name);
}
diff --git a/drivers/tty/ehv_bytechan.c b/drivers/tty/ehv_bytechan.c
index 0419b69e270f..4f485e88f60c 100644
--- a/drivers/tty/ehv_bytechan.c
+++ b/drivers/tty/ehv_bytechan.c
@@ -108,55 +108,23 @@ static void disable_tx_interrupt(struct ehv_bc_data *bc)
*
* The byte channel to be used for the console is specified via a "stdout"
* property in the /chosen node.
- *
- * For compatible with legacy device trees, we also look for a "stdout" alias.
*/
static int find_console_handle(void)
{
- struct device_node *np, *np2;
+ struct device_node *np = of_stdout;
const char *sprop = NULL;
const uint32_t *iprop;
- np = of_find_node_by_path("/chosen");
- if (np)
- sprop = of_get_property(np, "stdout-path", NULL);
-
- if (!np || !sprop) {
- of_node_put(np);
- np = of_find_node_by_name(NULL, "aliases");
- if (np)
- sprop = of_get_property(np, "stdout", NULL);
- }
-
- if (!sprop) {
- of_node_put(np);
- return 0;
- }
-
/* We don't care what the aliased node is actually called. We only
* care if it's compatible with "epapr,hv-byte-channel", because that
- * indicates that it's a byte channel node. We use a temporary
- * variable, 'np2', because we can't release 'np' until we're done with
- * 'sprop'.
+ * indicates that it's a byte channel node.
*/
- np2 = of_find_node_by_path(sprop);
- of_node_put(np);
- np = np2;
- if (!np) {
- pr_warning("ehv-bc: stdout node '%s' does not exist\n", sprop);
- return 0;
- }
-
- /* Is it a byte channel? */
- if (!of_device_is_compatible(np, "epapr,hv-byte-channel")) {
- of_node_put(np);
+ if (!np || !of_device_is_compatible(np, "epapr,hv-byte-channel"))
return 0;
- }
stdout_irq = irq_of_parse_and_map(np, 0);
if (stdout_irq == NO_IRQ) {
- pr_err("ehv-bc: no 'interrupts' property in %s node\n", sprop);
- of_node_put(np);
+ pr_err("ehv-bc: no 'interrupts' property in %s node\n", np->full_name);
return 0;
}
@@ -167,12 +135,9 @@ static int find_console_handle(void)
if (!iprop) {
pr_err("ehv-bc: no 'hv-handle' property in %s node\n",
np->name);
- of_node_put(np);
return 0;
}
stdout_bc = be32_to_cpu(*iprop);
-
- of_node_put(np);
return 1;
}
diff --git a/drivers/tty/hvc/hvc_opal.c b/drivers/tty/hvc/hvc_opal.c
index a585079b4b38..a2cc5f834c63 100644
--- a/drivers/tty/hvc/hvc_opal.c
+++ b/drivers/tty/hvc/hvc_opal.c
@@ -342,22 +342,13 @@ static void udbg_init_opal_common(void)
void __init hvc_opal_init_early(void)
{
- struct device_node *stdout_node = NULL;
+ struct device_node *stdout_node = of_node_get(of_stdout);
const __be32 *termno;
- const char *name = NULL;
const struct hv_ops *ops;
u32 index;
- /* find the boot console from /chosen/stdout */
- if (of_chosen)
- name = of_get_property(of_chosen, "linux,stdout-path", NULL);
- if (name) {
- stdout_node = of_find_node_by_path(name);
- if (!stdout_node) {
- pr_err("hvc_opal: Failed to locate default console!\n");
- return;
- }
- } else {
+ /* If the console wasn't in /chosen, try /ibm,opal */
+ if (!stdout_node) {
struct device_node *opal, *np;
/* Current OPAL takeover doesn't provide the stdout
diff --git a/drivers/tty/hvc/hvc_vio.c b/drivers/tty/hvc/hvc_vio.c
index b594abfbf21e..5618b5fc7500 100644
--- a/drivers/tty/hvc/hvc_vio.c
+++ b/drivers/tty/hvc/hvc_vio.c
@@ -404,42 +404,35 @@ module_exit(hvc_vio_exit);
void __init hvc_vio_init_early(void)
{
- struct device_node *stdout_node;
const __be32 *termno;
const char *name;
const struct hv_ops *ops;
/* find the boot console from /chosen/stdout */
- if (!of_chosen)
+ if (!of_stdout)
return;
- name = of_get_property(of_chosen, "linux,stdout-path", NULL);
- if (name == NULL)
- return;
- stdout_node = of_find_node_by_path(name);
- if (!stdout_node)
- return;
- name = of_get_property(stdout_node, "name", NULL);
+ name = of_get_property(of_stdout, "name", NULL);
if (!name) {
printk(KERN_WARNING "stdout node missing 'name' property!\n");
- goto out;
+ return;
}
/* Check if it's a virtual terminal */
if (strncmp(name, "vty", 3) != 0)
- goto out;
- termno = of_get_property(stdout_node, "reg", NULL);
+ return;
+ termno = of_get_property(of_stdout, "reg", NULL);
if (termno == NULL)
- goto out;
+ return;
hvterm_priv0.termno = of_read_number(termno, 1);
spin_lock_init(&hvterm_priv0.buf_lock);
hvterm_privs[0] = &hvterm_priv0;
/* Check the protocol */
- if (of_device_is_compatible(stdout_node, "hvterm1")) {
+ if (of_device_is_compatible(of_stdout, "hvterm1")) {
hvterm_priv0.proto = HV_PROTOCOL_RAW;
ops = &hvterm_raw_ops;
}
- else if (of_device_is_compatible(stdout_node, "hvterm-protocol")) {
+ else if (of_device_is_compatible(of_stdout, "hvterm-protocol")) {
hvterm_priv0.proto = HV_PROTOCOL_HVSI;
ops = &hvterm_hvsi_ops;
hvsilib_init(&hvterm_priv0.hvsi, hvc_get_chars, hvc_put_chars,
@@ -447,7 +440,7 @@ void __init hvc_vio_init_early(void)
/* HVSI, perform the handshake now */
hvsilib_establish(&hvterm_priv0.hvsi);
} else
- goto out;
+ return;
udbg_putc = udbg_hvc_putc;
udbg_getc = udbg_hvc_getc;
udbg_getc_poll = udbg_hvc_getc_poll;
@@ -456,14 +449,12 @@ void __init hvc_vio_init_early(void)
* backend for HVSI, only do udbg
*/
if (hvterm_priv0.proto == HV_PROTOCOL_HVSI)
- goto out;
+ return;
#endif
/* Check whether the user has requested a different console. */
if (!strstr(cmd_line, "console="))
add_preferred_console("hvc", 0, NULL);
hvc_instantiate(0, 0, ops);
-out:
- of_node_put(stdout_node);
}
/* call this from early_init() for a working debug console on
diff --git a/include/linux/of.h b/include/linux/of.h
index 9d9734056e39..f0d256273c83 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -113,6 +113,7 @@ static inline void of_node_put(struct device_node *node) { }
extern struct device_node *of_allnodes;
extern struct device_node *of_chosen;
extern struct device_node *of_aliases;
+extern struct device_node *of_stdout;
extern raw_spinlock_t devtree_lock;
static inline bool of_have_populated_dt(void)
--
1.9.1
^ permalink raw reply related [flat|nested] 5+ messages in thread