leds: leds-alix2c - take port address from MSR

This makes the LEDs driver for ALIX2.C boards work with Coreboot by looking up the port address in the MSR rather than hard-coding it. The BIOS scan also needed some tweaks as the string in Coreboot differs from the one in the legacy BIOS. Successfully tested with both the legacy tinyBIOS as well as Coreboot v3. Signed-off-by: Daniel Mack <daniel@caiaq.de> Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>

leds: leds-alix2c - take port address from MSR
This makes the LEDs driver for ALIX2.C boards work with Coreboot by looking up the port address in the MSR rather than hard-coding it. The BIOS scan also needed some tweaks as the string in Coreboot differs from the one in the legacy BIOS. Successfully tested with both the legacy tinyBIOS as well as Coreboot v3. Signed-off-by: Daniel Mack <daniel@caiaq.de> Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
Daniel Mack · Richard Purdie
1 parent a328e95b82
Showing 1 changed file with 84 additions and 31 deletions Side-by-side Diff
drivers/leds/leds-alix2.c
@@ -11,11 +11,24 @@
 #include <linux/module.h>
 #include <linux/platform_device.h>
 #include <linux/string.h>
+#include <linux/pci.h>
  
 static int force = 0;
 module_param(force, bool, 0444);
 MODULE_PARM_DESC(force, "Assume system has ALIX.2/ALIX.3 style LEDs");
  
+#define MSR_LBAR_GPIO		0x5140000C
+#define CS5535_GPIO_SIZE	256
+
+static u32 gpio_base;
+
+static struct pci_device_id divil_pci[] = {
+	{ PCI_DEVICE(PCI_VENDOR_ID_NS,  PCI_DEVICE_ID_NS_CS5535_ISA) },
+	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CS5536_ISA) },
+	{ } /* NULL entry */
+};
+MODULE_DEVICE_TABLE(pci, divil_pci);
+
 struct alix_led {
 	struct led_classdev cdev;
 	unsigned short port;
  
@@ -30,9 +43,9 @@
 		container_of(led_cdev, struct alix_led, cdev);
  
 	if (brightness)
-		outl(led_dev->on_value, led_dev->port);
+		outl(led_dev->on_value, gpio_base + led_dev->port);
 	else
-		outl(led_dev->off_value, led_dev->port);
+		outl(led_dev->off_value, gpio_base + led_dev->port);
 }
  
 static struct alix_led alix_leds[] = {
@@ -41,7 +54,7 @@
 			.name = "alix:1",
 			.brightness_set = alix_led_set,
 		},
-		.port = 0x6100,
+		.port = 0x00,
 		.on_value = 1 << 22,
 		.off_value = 1 << 6,
 	},
@@ -50,7 +63,7 @@
 			.name = "alix:2",
 			.brightness_set = alix_led_set,
 		},
-		.port = 0x6180,
+		.port = 0x80,
 		.on_value = 1 << 25,
 		.off_value = 1 << 9,
 	},
@@ -59,7 +72,7 @@
 			.name = "alix:3",
 			.brightness_set = alix_led_set,
 		},
-		.port = 0x6180,
+		.port = 0x80,
 		.on_value = 1 << 27,
 		.off_value = 1 << 11,
 	},
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
@@ -101,65 +114,105 @@
 	},
 };
  
-static int __init alix_present(void)
+static int __init alix_present(unsigned long bios_phys,
+				const char *alix_sig,
+				size_t alix_sig_len)
 {
-	const unsigned long bios_phys = 0x000f0000;
 	const size_t bios_len = 0x00010000;
-	const char alix_sig[] = "PC Engines ALIX.";
-	const size_t alix_sig_len = sizeof(alix_sig) - 1;
-
 	const char *bios_virt;
 	const char *scan_end;
 	const char *p;
-	int ret = 0;
+	char name[64];
  
 	if (force) {
 		printk(KERN_NOTICE "%s: forced to skip BIOS test, "
 		       "assume system has ALIX.2 style LEDs\n",
 		       KBUILD_MODNAME);
-		ret = 1;
-		goto out;
+		return 1;
 	}
  
 	bios_virt = phys_to_virt(bios_phys);
 	scan_end = bios_virt + bios_len - (alix_sig_len + 2);
 	for (p = bios_virt; p < scan_end; p++) {
 		const char *tail;
+		char *a;
  
-		if (memcmp(p, alix_sig, alix_sig_len) != 0) {
+		if (memcmp(p, alix_sig, alix_sig_len) != 0)
 			continue;
-		}
  
+		memcpy(name, p, sizeof(name));
+
+		/* remove the first \0 character from string */
+		a = strchr(name, '\0');
+		if (a)
+			*a = ' ';
+
+		/* cut the string at a newline */
+		a = strchr(name, '\r');
+		if (a)
+			*a = '\0';
+
 		tail = p + alix_sig_len;
-		if ((tail[0] == '2' || tail[0] == '3') && tail[1] == '\0') {
+		if ((tail[0] == '2' || tail[0] == '3')) {
 			printk(KERN_INFO
 			       "%s: system is recognized as \"%s\"\n",
-			       KBUILD_MODNAME, p);
-			ret = 1;
-			break;
+			       KBUILD_MODNAME, name);
+			return 1;
 		}
 	}
  
-out:
-	return ret;
+	return 0;
 }
  
 static struct platform_device *pdev;
  
-static int __init alix_led_init(void)
+static int __init alix_pci_led_init(void)
 {
-	int ret;
+	u32 low, hi;
  
-	if (!alix_present()) {
-		ret = -ENODEV;
-		goto out;
+	if (pci_dev_present(divil_pci) == 0) {
+		printk(KERN_WARNING KBUILD_MODNAME": DIVIL not found\n");
+		return -ENODEV;
 	}
  
-	/* enable output on GPIO for LED 1,2,3 */
-	outl(1 << 6, 0x6104);
-	outl(1 << 9, 0x6184);
-	outl(1 << 11, 0x6184);
+	/* Grab the GPIO I/O range */
+	rdmsr(MSR_LBAR_GPIO, low, hi);
  
+	/* Check the mask and whether GPIO is enabled (sanity check) */
+	if (hi != 0x0000f001) {
+		printk(KERN_WARNING KBUILD_MODNAME": GPIO not enabled\n");
+		return -ENODEV;
+	}
+
+	/* Mask off the IO base address */
+	gpio_base = low & 0x0000ff00;
+
+	if (!request_region(gpio_base, CS5535_GPIO_SIZE, KBUILD_MODNAME)) {
+		printk(KERN_ERR KBUILD_MODNAME": can't allocate I/O for GPIO\n");
+		return -ENODEV;
+	}
+
+	/* Set GPIO function to output */
+	outl(1 << 6, gpio_base + 0x04);
+	outl(1 << 9, gpio_base + 0x84);
+	outl(1 << 11, gpio_base + 0x84);
+
+	return 0;
+}
+
+static int __init alix_led_init(void)
+{
+	int ret = -ENODEV;
+	const char tinybios_sig[] = "PC Engines ALIX.";
+	const char coreboot_sig[] = "PC Engines\0ALIX.";
+
+	if (alix_present(0xf0000, tinybios_sig, sizeof(tinybios_sig) - 1) ||
+	    alix_present(0x500, coreboot_sig, sizeof(coreboot_sig) - 1))
+		ret = alix_pci_led_init();
+
+	if (ret < 0)
+		return ret;
+
 	pdev = platform_device_register_simple(KBUILD_MODNAME, -1, NULL, 0);
 	if (!IS_ERR(pdev)) {
 		ret = platform_driver_probe(&alix_led_driver, alix_led_probe);
@@ -168,7 +221,6 @@
 	} else
 		ret = PTR_ERR(pdev);
  
-out:
 	return ret;
 }
  
@@ -176,6 +228,7 @@
 {
 	platform_device_unregister(pdev);
 	platform_driver_unregister(&alix_led_driver);
+	release_region(gpio_base, CS5535_GPIO_SIZE);
 }
  
 module_init(alix_led_init);
...	...	@@ -11,11 +11,24 @@
11	11	#include <linux/module.h>
12	12	#include <linux/platform_device.h>
13	13	#include <linux/string.h>
	14	+#include <linux/pci.h>
14	15
15	16	static int force = 0;
16	17	module_param(force, bool, 0444);
17	18	MODULE_PARM_DESC(force, "Assume system has ALIX.2/ALIX.3 style LEDs");
18	19
	20	+#define MSR_LBAR_GPIO 0x5140000C
	21	+#define CS5535_GPIO_SIZE 256
	22	+
	23	+static u32 gpio_base;
	24	+
	25	+static struct pci_device_id divil_pci[] = {
	26	+ { PCI_DEVICE(PCI_VENDOR_ID_NS, PCI_DEVICE_ID_NS_CS5535_ISA) },
	27	+ { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CS5536_ISA) },
	28	+ { } /* NULL entry */
	29	+};
	30	+MODULE_DEVICE_TABLE(pci, divil_pci);
	31	+
19	32	struct alix_led {
20	33	struct led_classdev cdev;
21	34	unsigned short port;
22	35
...	...	@@ -30,9 +43,9 @@
30	43	container_of(led_cdev, struct alix_led, cdev);
31	44
32	45	if (brightness)
33		- outl(led_dev->on_value, led_dev->port);
	46	+ outl(led_dev->on_value, gpio_base + led_dev->port);
34	47	else
35		- outl(led_dev->off_value, led_dev->port);
	48	+ outl(led_dev->off_value, gpio_base + led_dev->port);
36	49	}
37	50
38	51	static struct alix_led alix_leds[] = {
...	...	@@ -41,7 +54,7 @@
41	54	.name = "alix:1",
42	55	.brightness_set = alix_led_set,
43	56	},
44		- .port = 0x6100,
	57	+ .port = 0x00,
45	58	.on_value = 1 << 22,
46	59	.off_value = 1 << 6,
47	60	},
...	...	@@ -50,7 +63,7 @@
50	63	.name = "alix:2",
51	64	.brightness_set = alix_led_set,
52	65	},
53		- .port = 0x6180,
	66	+ .port = 0x80,
54	67	.on_value = 1 << 25,
55	68	.off_value = 1 << 9,
56	69	},
...	...	@@ -59,7 +72,7 @@
59	72	.name = "alix:3",
60	73	.brightness_set = alix_led_set,
61	74	},
62		- .port = 0x6180,
	75	+ .port = 0x80,
63	76	.on_value = 1 << 27,
64	77	.off_value = 1 << 11,
65	78	},
66	79
67	80
68	81
69	82
70	83
71	84
72	85
73	86
74	87
75	88
76	89
77	90
78	91
79	92
80	93
81	94
...	...	@@ -101,65 +114,105 @@
101	114	},
102	115	};
103	116
104		-static int __init alix_present(void)
	117	+static int __init alix_present(unsigned long bios_phys,
	118	+ const char *alix_sig,
	119	+ size_t alix_sig_len)
105	120	{
106		- const unsigned long bios_phys = 0x000f0000;
107	121	const size_t bios_len = 0x00010000;
108		- const char alix_sig[] = "PC Engines ALIX.";
109		- const size_t alix_sig_len = sizeof(alix_sig) - 1;
110		-
111	122	const char *bios_virt;
112	123	const char *scan_end;
113	124	const char *p;
114		- int ret = 0;
	125	+ char name[64];
115	126
116	127	if (force) {
117	128	printk(KERN_NOTICE "%s: forced to skip BIOS test, "
118	129	"assume system has ALIX.2 style LEDs\n",
119	130	KBUILD_MODNAME);
120		- ret = 1;
121		- goto out;
	131	+ return 1;
122	132	}
123	133
124	134	bios_virt = phys_to_virt(bios_phys);
125	135	scan_end = bios_virt + bios_len - (alix_sig_len + 2);
126	136	for (p = bios_virt; p < scan_end; p++) {
127	137	const char *tail;
	138	+ char *a;
128	139
129		- if (memcmp(p, alix_sig, alix_sig_len) != 0) {
	140	+ if (memcmp(p, alix_sig, alix_sig_len) != 0)
130	141	continue;
131		- }
132	142
	143	+ memcpy(name, p, sizeof(name));
	144	+
	145	+ /* remove the first \0 character from string */
	146	+ a = strchr(name, '\0');
	147	+ if (a)
	148	+ *a = ' ';
	149	+
	150	+ /* cut the string at a newline */
	151	+ a = strchr(name, '\r');
	152	+ if (a)
	153	+ *a = '\0';
	154	+
133	155	tail = p + alix_sig_len;
134		- if ((tail[0] == '2' \|\| tail[0] == '3') && tail[1] == '\0') {
	156	+ if ((tail[0] == '2' \|\| tail[0] == '3')) {
135	157	printk(KERN_INFO
136	158	"%s: system is recognized as \"%s\"\n",
137		- KBUILD_MODNAME, p);
138		- ret = 1;
139		- break;
	159	+ KBUILD_MODNAME, name);
	160	+ return 1;
140	161	}
141	162	}
142	163
143		-out:
144		- return ret;
	164	+ return 0;
145	165	}
146	166
147	167	static struct platform_device *pdev;
148	168
149		-static int __init alix_led_init(void)
	169	+static int __init alix_pci_led_init(void)
150	170	{
151		- int ret;
	171	+ u32 low, hi;
152	172
153		- if (!alix_present()) {
154		- ret = -ENODEV;
155		- goto out;
	173	+ if (pci_dev_present(divil_pci) == 0) {
	174	+ printk(KERN_WARNING KBUILD_MODNAME": DIVIL not found\n");
	175	+ return -ENODEV;
156	176	}
157	177
158		- /* enable output on GPIO for LED 1,2,3 */
159		- outl(1 << 6, 0x6104);
160		- outl(1 << 9, 0x6184);
161		- outl(1 << 11, 0x6184);
	178	+ /* Grab the GPIO I/O range */
	179	+ rdmsr(MSR_LBAR_GPIO, low, hi);
162	180
	181	+ /* Check the mask and whether GPIO is enabled (sanity check) */
	182	+ if (hi != 0x0000f001) {
	183	+ printk(KERN_WARNING KBUILD_MODNAME": GPIO not enabled\n");
	184	+ return -ENODEV;
	185	+ }
	186	+
	187	+ /* Mask off the IO base address */
	188	+ gpio_base = low & 0x0000ff00;
	189	+
	190	+ if (!request_region(gpio_base, CS5535_GPIO_SIZE, KBUILD_MODNAME)) {
	191	+ printk(KERN_ERR KBUILD_MODNAME": can't allocate I/O for GPIO\n");
	192	+ return -ENODEV;
	193	+ }
	194	+
	195	+ /* Set GPIO function to output */
	196	+ outl(1 << 6, gpio_base + 0x04);
	197	+ outl(1 << 9, gpio_base + 0x84);
	198	+ outl(1 << 11, gpio_base + 0x84);
	199	+
	200	+ return 0;
	201	+}
	202	+
	203	+static int __init alix_led_init(void)
	204	+{
	205	+ int ret = -ENODEV;
	206	+ const char tinybios_sig[] = "PC Engines ALIX.";
	207	+ const char coreboot_sig[] = "PC Engines\0ALIX.";
	208	+
	209	+ if (alix_present(0xf0000, tinybios_sig, sizeof(tinybios_sig) - 1) \|\|
	210	+ alix_present(0x500, coreboot_sig, sizeof(coreboot_sig) - 1))
	211	+ ret = alix_pci_led_init();
	212	+
	213	+ if (ret < 0)
	214	+ return ret;
	215	+
163	216	pdev = platform_device_register_simple(KBUILD_MODNAME, -1, NULL, 0);
164	217	if (!IS_ERR(pdev)) {
165	218	ret = platform_driver_probe(&alix_led_driver, alix_led_probe);
...	...	@@ -168,7 +221,6 @@
168	221	} else
169	222	ret = PTR_ERR(pdev);
170	223
171		-out:
172	224	return ret;
173	225	}
174	226
...	...	@@ -176,6 +228,7 @@
176	228	{
177	229	platform_device_unregister(pdev);
178	230	platform_driver_unregister(&alix_led_driver);
	231	+ release_region(gpio_base, CS5535_GPIO_SIZE);
179	232	}
180	233
181	234	module_init(alix_led_init);