Add simple hwconfig infrastructure

This patch implements simple hwconfig infrastructure: an interface for software knobs to control a hardware. This is very simple implementation, i.e. it is implemented via `hwconfig' environment variable. Later we could write some "hwconfig <enable|disable|list>" commands, ncurses interface for Award BIOS-like interface, and frame-buffer interface for AMI GUI[1] BIOS-like interface with mouse support[2]. Current implementation details/limitations: 1. Doesn't support options dependencies and mutual exclusion. We can implement this by integrating apt-get[3] into the u-boot. But I didn't bother yet. 2. Since we don't implement hwconfig command, i.e. we're working with the environement directly, there is no way to tell that toggling a particular option will need a reboot to take an effect. So, for now it's advised to always reboot the target after modifying hwconfig variable. 3. We support hwconfig options with arguments. For example, set hwconfig dr_usb:mode=peripheral,phy_type=ulpi That means: - dr_usb - enable Dual-Role USB controller; - dr_usb:mode=peripheral - USB in Function mode; - dr_usb:phy_type=ulpi - USB should work with ULPI PHYs; The purpose of this simple implementation is to define some internal API and then we can continue improving user experience by adding more mature interface, like hwconfig command with bells and whistles. Or not adding, if we feel that current interface fits its needs. [1] http://en.wikipedia.org/wiki/American_Megatrends [2] Regarding ncurses and GUI with mouse support -- I'm just kidding. [3] The comment regarding apt-get is also a joke, meaning that dependency tracking could be non-trivial. For example, for enabling HW feature X we may need to disable Y, and turn Z into reduced mode (like RMII-only interface for ethernet, no MII). It's quite trivial to implement simple cases though. Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com> Acked-by: Kim Phillips <kim.phillips@freescale.com>

Add simple hwconfig infrastructure
This patch implements simple hwconfig infrastructure: an interface for software knobs to control a hardware. This is very simple implementation, i.e. it is implemented via `hwconfig' environment variable. Later we could write some "hwconfig <enable|disable|list>" commands, ncurses interface for Award BIOS-like interface, and frame-buffer interface for AMI GUI[1] BIOS-like interface with mouse support[2]. Current implementation details/limitations: 1. Doesn't support options dependencies and mutual exclusion. We can implement this by integrating apt-get[3] into the u-boot. But I didn't bother yet. 2. Since we don't implement hwconfig command, i.e. we're working with the environement directly, there is no way to tell that toggling a particular option will need a reboot to take an effect. So, for now it's advised to always reboot the target after modifying hwconfig variable. 3. We support hwconfig options with arguments. For example, set hwconfig dr_usb:mode=peripheral,phy_type=ulpi That means: - dr_usb - enable Dual-Role USB controller; - dr_usb:mode=peripheral - USB in Function mode; - dr_usb:phy_type=ulpi - USB should work with ULPI PHYs; The purpose of this simple implementation is to define some internal API and then we can continue improving user experience by adding more mature interface, like hwconfig command with bells and whistles. Or not adding, if we feel that current interface fits its needs. [1] http://en.wikipedia.org/wiki/American_Megatrends [2] Regarding ncurses and GUI with mouse support -- I'm just kidding. [3] The comment regarding apt-get is also a joke, meaning that dependency tracking could be non-trivial. For example, for enabling HW feature X we may need to disable Y, and turn Z into reduced mode (like RMII-only interface for ethernet, no MII). It's quite trivial to implement simple cases though. Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com> Acked-by: Kim Phillips <kim.phillips@freescale.com>
Anton Vorontsov · Wolfgang Denk
1 parent cd21a458da
Showing 3 changed files with 280 additions and 0 deletions Side-by-side Diff
common/Makefile
common/hwconfig.c
include/hwconfig.h
@@ -151,6 +151,7 @@
 # others
 COBJS-$(CONFIG_DDR_SPD) += ddr_spd.o
 COBJS-$(CONFIG_CMD_DOC) += docecc.o
+COBJS-$(CONFIG_HWCONFIG) += hwconfig.o
 COBJS-$(CONFIG_CONSOLE_MUX) += iomux.o
 COBJS-y += flash.o
 COBJS-$(CONFIG_CMD_KGDB) += kgdb.o
+/*
+ * An inteface for configuring a hardware via u-boot environment.
+ *
+ * Copyright (c) 2009  MontaVista Software, Inc.
+ *
+ * Author: Anton Vorontsov <avorontsov@ru.mvista.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ */
+
+#include <config.h>
+#include <common.h>
+#include <exports.h>
+#include <hwconfig.h>
+#include <linux/types.h>
+#include <linux/string.h>
+
+static const char *hwconfig_parse(const char *opts, size_t maxlen,
+				  const char *opt, char stopch, char eqch,
+				  size_t *arglen)
+{
+	size_t optlen = strlen(opt);
+	char *str;
+	const char *start = opts;
+	const char *end;
+
+next:
+	str = strstr(opts, opt);
+	end = str + optlen;
+	if (end - start > maxlen)
+		return NULL;
+
+	if (str && (str == opts || str[-1] == stopch) &&
+			(*end == stopch || *end == eqch || *end == '\0')) {
+		const char *arg_end;
+
+		if (!arglen)
+			return str;
+
+		if (*end != eqch)
+			return NULL;
+
+		arg_end = strchr(str, stopch);
+		if (!arg_end)
+			*arglen = min(maxlen, strlen(str)) - optlen - 1;
+		else
+			*arglen = arg_end - end - 1;
+
+		return end + 1;
+	} else if (str) {
+		opts = end;
+		goto next;
+	}
+	return NULL;
+}
+
+const char *cpu_hwconfig __attribute__((weak));
+const char *board_hwconfig __attribute__((weak));
+
+static const char *__hwconfig(const char *opt, size_t *arglen)
+{
+	const char *env_hwconfig = getenv("hwconfig");
+
+	if (env_hwconfig)
+		return hwconfig_parse(env_hwconfig, strlen(env_hwconfig),
+				      opt, ';', ':', arglen);
+
+	if (board_hwconfig)
+		return hwconfig_parse(board_hwconfig, strlen(board_hwconfig),
+				      opt, ';', ':', arglen);
+
+	if (cpu_hwconfig)
+		return hwconfig_parse(cpu_hwconfig, strlen(cpu_hwconfig),
+				      opt, ';', ':', arglen);
+
+	return NULL;
+}
+
+/*
+ * hwconfig - query if a particular hwconfig option is specified
+ * @opt:	a string representing an option
+ *
+ * This call can be used to find out whether U-Boot should configure
+ * a particular hardware option.
+ *
+ * Returns non-zero value if the hardware option can be used and thus
+ * should be configured, 0 otherwise.
+ *
+ * This function also returns non-zero value if CONFIG_HWCONFIG is
+ * undefined.
+ *
+ * Returning non-zero value without CONFIG_HWCONFIG has its crucial
+ * purpose: the hwconfig() call should be a "transparent" interface,
+ * e.g. if a board doesn't need hwconfig facility, then we assume
+ * that the board file only calls things that are actually used, so
+ * hwconfig() will always return true result.
+ */
+int hwconfig(const char *opt)
+{
+	return !!__hwconfig(opt, NULL);
+}
+
+/*
+ * hwconfig_arg - get hwconfig option's argument
+ * @opt:	a string representing an option
+ * @arglen:	a pointer to an allocated size_t variable
+ *
+ * Unlike hwconfig() function, this function returns a pointer to the
+ * start of the hwconfig arguments, if option is not found or it has
+ * no specified arguments, the function returns NULL pointer.
+ *
+ * If CONFIG_HWCONFIG is undefined, the function returns "", and
+ * arglen is set to 0.
+ */
+const char *hwconfig_arg(const char *opt, size_t *arglen)
+{
+	return __hwconfig(opt, arglen);
+}
+
+/*
+ * hwconfig_arg_cmp - compare hwconfig option's argument
+ * @opt:	a string representing an option
+ * @arg:	a string for comparing an option's argument
+ *
+ * This call is similar to hwconfig_arg, but instead of returning
+ * hwconfig argument and its length, it is comparing it to @arg.
+ *
+ * Returns non-zero value if @arg matches, 0 otherwise.
+ *
+ * If CONFIG_HWCONFIG is undefined, the function returns a non-zero
+ * value, i.e. the argument matches.
+ */
+int hwconfig_arg_cmp(const char *opt, const char *arg)
+{
+	const char *argstr;
+	size_t arglen;
+
+	argstr = hwconfig_arg(opt, &arglen);
+	if (!argstr || arglen != strlen(arg))
+		return 0;
+
+	return !strncmp(argstr, arg, arglen);
+}
+
+/*
+ * hwconfig_sub - query if a particular hwconfig sub-option is specified
+ * @opt:	a string representing an option
+ * @subopt:	a string representing a sub-option
+ *
+ * This call is similar to hwconfig(), except that it takes additional
+ * argument @subopt. In this example:
+ * 	"dr_usb:mode=peripheral"
+ * "dr_usb" is an option, "mode" is a sub-option, and "peripheral" is its
+ * argument.
+ */
+int hwconfig_sub(const char *opt, const char *subopt)
+{
+	size_t arglen;
+	const char *arg;
+
+	arg = __hwconfig(opt, &arglen);
+	if (!arg)
+		return 0;
+	return !!hwconfig_parse(arg, arglen, subopt, ',', '=', NULL);
+}
+
+/*
+ * hwconfig_subarg - get hwconfig sub-option's argument
+ * @opt:	a string representing an option
+ * @subopt:	a string representing a sub-option
+ * @subarglen:	a pointer to an allocated size_t variable
+ *
+ * This call is similar to hwconfig_arg(), except that it takes an additional
+ * argument @subopt, and so works with sub-options.
+ */
+const char *hwconfig_subarg(const char *opt, const char *subopt,
+			    size_t *subarglen)
+{
+	size_t arglen;
+	const char *arg;
+
+	arg = __hwconfig(opt, &arglen);
+	if (!arg)
+		return NULL;
+	return hwconfig_parse(arg, arglen, subopt, ',', '=', subarglen);
+}
+
+/*
+ * hwconfig_arg_cmp - compare hwconfig sub-option's argument
+ * @opt:	a string representing an option
+ * @subopt:	a string representing a sub-option
+ * @subarg:	a string for comparing an sub-option's argument
+ *
+ * This call is similar to hwconfig_arg_cmp, except that it takes an additional
+ * argument @subopt, and so works with sub-options.
+ */
+int hwconfig_subarg_cmp(const char *opt, const char *subopt, const char *subarg)
+{
+	const char *argstr;
+	size_t arglen;
+
+	argstr = hwconfig_subarg(opt, subopt, &arglen);
+	if (!argstr || arglen != strlen(subarg))
+		return 0;
+
+	return !strncmp(argstr, subarg, arglen);
+}
+/*
+ * An inteface for configuring a hardware via u-boot environment.
+ *
+ * Copyright (c) 2009  MontaVista Software, Inc.
+ *
+ * Author: Anton Vorontsov <avorontsov@ru.mvista.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ */
+
+#ifndef _HWCONFIG_H
+#define _HWCONFIG_H
+
+#include <linux/types.h>
+#include <asm/errno.h>
+
+#ifdef CONFIG_HWCONFIG
+
+extern int hwconfig(const char *opt);
+extern const char *hwconfig_arg(const char *opt, size_t *arglen);
+extern int hwconfig_arg_cmp(const char *opt, const char *arg);
+extern int hwconfig_sub(const char *opt, const char *subopt);
+extern const char *hwconfig_subarg(const char *opt, const char *subopt,
+				   size_t *subarglen);
+extern int hwconfig_subarg_cmp(const char *opt, const char *subopt,
+			       const char *subarg);
+
+#else
+
+static inline int hwconfig(const char *opt)
+{
+	return -ENOSYS;
+}
+
+static inline const char *hwconfig_arg(const char *opt, size_t *arglen)
+{
+	*arglen = 0;
+	return "";
+}
+
+static inline int hwconfig_arg_cmp(const char *opt, const char *arg)
+{
+	return -ENOSYS;
+}
+
+static inline int hwconfig_sub(const char *opt, const char *subopt)
+{
+	return -ENOSYS;
+}
+
+static inline const char *hwconfig_subarg(const char *opt, const char *subopt,
+					  size_t *subarglen)
+{
+	*subarglen = 0;
+	return "";
+}
+
+static inline int hwconfig_subarg_cmp(const char *opt, const char *subopt,
+				      const char *subarg)
+{
+	return -ENOSYS;
+}
+
+#endif /* CONFIG_HWCONFIG */
+
+#endif /* _HWCONFIG_H */
...	...	@@ -151,6 +151,7 @@
151	151	# others
152	152	COBJS-$(CONFIG_DDR_SPD) += ddr_spd.o
153	153	COBJS-$(CONFIG_CMD_DOC) += docecc.o
	154	+COBJS-$(CONFIG_HWCONFIG) += hwconfig.o
154	155	COBJS-$(CONFIG_CONSOLE_MUX) += iomux.o
155	156	COBJS-y += flash.o
156	157	COBJS-$(CONFIG_CMD_KGDB) += kgdb.o
	1	+/*
	2	+ * An inteface for configuring a hardware via u-boot environment.
	3	+ *
	4	+ * Copyright (c) 2009 MontaVista Software, Inc.
	5	+ *
	6	+ * Author: Anton Vorontsov <avorontsov@ru.mvista.com>
	7	+ *
	8	+ * This program is free software; you can redistribute it and/or
	9	+ * modify it under the terms of the GNU General Public License as
	10	+ * published by the Free Software Foundation; either version 2 of
	11	+ * the License, or (at your option) any later version.
	12	+ */
	13	+
	14	+#include <config.h>
	15	+#include <common.h>
	16	+#include <exports.h>
	17	+#include <hwconfig.h>
	18	+#include <linux/types.h>
	19	+#include <linux/string.h>
	20	+
	21	+static const char hwconfig_parse(const char opts, size_t maxlen,
	22	+ const char *opt, char stopch, char eqch,
	23	+ size_t *arglen)
	24	+{
	25	+ size_t optlen = strlen(opt);
	26	+ char *str;
	27	+ const char *start = opts;
	28	+ const char *end;
	29	+
	30	+next:
	31	+ str = strstr(opts, opt);
	32	+ end = str + optlen;
	33	+ if (end - start > maxlen)
	34	+ return NULL;
	35	+
	36	+ if (str && (str == opts \|\| str[-1] == stopch) &&
	37	+ (end == stopch \|\| end == eqch \|\| *end == '\0')) {
	38	+ const char *arg_end;
	39	+
	40	+ if (!arglen)
	41	+ return str;
	42	+
	43	+ if (*end != eqch)
	44	+ return NULL;
	45	+
	46	+ arg_end = strchr(str, stopch);
	47	+ if (!arg_end)
	48	+ *arglen = min(maxlen, strlen(str)) - optlen - 1;
	49	+ else
	50	+ *arglen = arg_end - end - 1;
	51	+
	52	+ return end + 1;
	53	+ } else if (str) {
	54	+ opts = end;
	55	+ goto next;
	56	+ }
	57	+ return NULL;
	58	+}
	59	+
	60	+const char *cpu_hwconfig __attribute__((weak));
	61	+const char *board_hwconfig __attribute__((weak));
	62	+
	63	+static const char __hwconfig(const char opt, size_t *arglen)
	64	+{
	65	+ const char *env_hwconfig = getenv("hwconfig");
	66	+
	67	+ if (env_hwconfig)
	68	+ return hwconfig_parse(env_hwconfig, strlen(env_hwconfig),
	69	+ opt, ';', ':', arglen);
	70	+
	71	+ if (board_hwconfig)
	72	+ return hwconfig_parse(board_hwconfig, strlen(board_hwconfig),
	73	+ opt, ';', ':', arglen);
	74	+
	75	+ if (cpu_hwconfig)
	76	+ return hwconfig_parse(cpu_hwconfig, strlen(cpu_hwconfig),
	77	+ opt, ';', ':', arglen);
	78	+
	79	+ return NULL;
	80	+}
	81	+
	82	+/*
	83	+ * hwconfig - query if a particular hwconfig option is specified
	84	+ * @opt: a string representing an option
	85	+ *
	86	+ * This call can be used to find out whether U-Boot should configure
	87	+ * a particular hardware option.
	88	+ *
	89	+ * Returns non-zero value if the hardware option can be used and thus
	90	+ * should be configured, 0 otherwise.
	91	+ *
	92	+ * This function also returns non-zero value if CONFIG_HWCONFIG is
	93	+ * undefined.
	94	+ *
	95	+ * Returning non-zero value without CONFIG_HWCONFIG has its crucial
	96	+ * purpose: the hwconfig() call should be a "transparent" interface,
	97	+ * e.g. if a board doesn't need hwconfig facility, then we assume
	98	+ * that the board file only calls things that are actually used, so
	99	+ * hwconfig() will always return true result.
	100	+ */
	101	+int hwconfig(const char *opt)
	102	+{
	103	+ return !!__hwconfig(opt, NULL);
	104	+}
	105	+
	106	+/*
	107	+ * hwconfig_arg - get hwconfig option's argument
	108	+ * @opt: a string representing an option
	109	+ * @arglen: a pointer to an allocated size_t variable
	110	+ *
	111	+ * Unlike hwconfig() function, this function returns a pointer to the
	112	+ * start of the hwconfig arguments, if option is not found or it has
	113	+ * no specified arguments, the function returns NULL pointer.
	114	+ *
	115	+ * If CONFIG_HWCONFIG is undefined, the function returns "", and
	116	+ * arglen is set to 0.
	117	+ */
	118	+const char hwconfig_arg(const char opt, size_t *arglen)
	119	+{
	120	+ return __hwconfig(opt, arglen);
	121	+}
	122	+
	123	+/*
	124	+ * hwconfig_arg_cmp - compare hwconfig option's argument
	125	+ * @opt: a string representing an option
	126	+ * @arg: a string for comparing an option's argument
	127	+ *
	128	+ * This call is similar to hwconfig_arg, but instead of returning
	129	+ * hwconfig argument and its length, it is comparing it to @arg.
	130	+ *
	131	+ * Returns non-zero value if @arg matches, 0 otherwise.
	132	+ *
	133	+ * If CONFIG_HWCONFIG is undefined, the function returns a non-zero
	134	+ * value, i.e. the argument matches.
	135	+ */
	136	+int hwconfig_arg_cmp(const char opt, const char arg)
	137	+{
	138	+ const char *argstr;
	139	+ size_t arglen;
	140	+
	141	+ argstr = hwconfig_arg(opt, &arglen);
	142	+ if (!argstr \|\| arglen != strlen(arg))
	143	+ return 0;
	144	+
	145	+ return !strncmp(argstr, arg, arglen);
	146	+}
	147	+
	148	+/*
	149	+ * hwconfig_sub - query if a particular hwconfig sub-option is specified
	150	+ * @opt: a string representing an option
	151	+ * @subopt: a string representing a sub-option
	152	+ *
	153	+ * This call is similar to hwconfig(), except that it takes additional
	154	+ * argument @subopt. In this example:
	155	+ * "dr_usb:mode=peripheral"
	156	+ * "dr_usb" is an option, "mode" is a sub-option, and "peripheral" is its
	157	+ * argument.
	158	+ */
	159	+int hwconfig_sub(const char opt, const char subopt)
	160	+{
	161	+ size_t arglen;
	162	+ const char *arg;
	163	+
	164	+ arg = __hwconfig(opt, &arglen);
	165	+ if (!arg)
	166	+ return 0;
	167	+ return !!hwconfig_parse(arg, arglen, subopt, ',', '=', NULL);
	168	+}
	169	+
	170	+/*
	171	+ * hwconfig_subarg - get hwconfig sub-option's argument
	172	+ * @opt: a string representing an option
	173	+ * @subopt: a string representing a sub-option
	174	+ * @subarglen: a pointer to an allocated size_t variable
	175	+ *
	176	+ * This call is similar to hwconfig_arg(), except that it takes an additional
	177	+ * argument @subopt, and so works with sub-options.
	178	+ */
	179	+const char hwconfig_subarg(const char opt, const char *subopt,
	180	+ size_t *subarglen)
	181	+{
	182	+ size_t arglen;
	183	+ const char *arg;
	184	+
	185	+ arg = __hwconfig(opt, &arglen);
	186	+ if (!arg)
	187	+ return NULL;
	188	+ return hwconfig_parse(arg, arglen, subopt, ',', '=', subarglen);
	189	+}
	190	+
	191	+/*
	192	+ * hwconfig_arg_cmp - compare hwconfig sub-option's argument
	193	+ * @opt: a string representing an option
	194	+ * @subopt: a string representing a sub-option
	195	+ * @subarg: a string for comparing an sub-option's argument
	196	+ *
	197	+ * This call is similar to hwconfig_arg_cmp, except that it takes an additional
	198	+ * argument @subopt, and so works with sub-options.
	199	+ */
	200	+int hwconfig_subarg_cmp(const char opt, const char subopt, const char *subarg)
	201	+{
	202	+ const char *argstr;
	203	+ size_t arglen;
	204	+
	205	+ argstr = hwconfig_subarg(opt, subopt, &arglen);
	206	+ if (!argstr \|\| arglen != strlen(subarg))
	207	+ return 0;
	208	+
	209	+ return !strncmp(argstr, subarg, arglen);
	210	+}