---

yaml
---
r: 45482
b: refs/heads/master
c: 9863be5
h: refs/heads/master
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: f73ca1b76c6880b934d3ef566c1592efc80bb759
+refs/heads/master: 9863be598ed068613996af8da71d9fd976a0ab2d

trunk/drivers/char/hw_random/intel-rng.c

@@ -143,6 +143,11 @@ static const struct pci_device_id pci_tbl[] = {
 };
 MODULE_DEVICE_TABLE(pci, pci_tbl);
 
+static __initdata int no_fwh_detect;
+module_param(no_fwh_detect, int, 0);
+MODULE_PARM_DESC(no_fwh_detect, "Skip FWH detection:\n"
+                                " positive value - skip if FWH space locked read-only\n"
+                                " negative value - skip always");
 
 static inline u8 hwstatus_get(void __iomem *mem)
 {
@@ -240,6 +245,11 @@ static int __init mod_init(void)
 	if (!dev)
 		goto out; /* Device not found. */
 
+	if (no_fwh_detect < 0) {
+		pci_dev_put(dev);
+		goto fwh_done;
+	}
+
 	/* Check for Intel 82802 */
 	if (dev->device < 0x2640) {
 		fwh_dec_en1_off = FWH_DEC_EN1_REG_OLD;
@@ -252,6 +262,23 @@ static int __init mod_init(void)
 	pci_read_config_byte(dev, fwh_dec_en1_off, &fwh_dec_en1_val);
 	pci_read_config_byte(dev, bios_cntl_off, &bios_cntl_val);
 
+	if ((bios_cntl_val &
+	     (BIOS_CNTL_LOCK_ENABLE_MASK|BIOS_CNTL_WRITE_ENABLE_MASK))
+	    == BIOS_CNTL_LOCK_ENABLE_MASK) {
+		static __initdata /*const*/ char warning[] =
+			KERN_WARNING PFX "Firmware space is locked read-only. If you can't or\n"
+			KERN_WARNING PFX "don't want to disable this in firmware setup, and if\n"
+			KERN_WARNING PFX "you are certain that your system has a functional\n"
+			KERN_WARNING PFX "RNG, try using the 'no_fwh_detect' option.\n";
+
+		pci_dev_put(dev);
+		if (no_fwh_detect)
+			goto fwh_done;
+		printk(warning);
+		err = -EBUSY;
+		goto out;
+	}
+
 	mem = ioremap_nocache(INTEL_FWH_ADDR, INTEL_FWH_ADDR_LEN);
 	if (mem == NULL) {
 		pci_dev_put(dev);
@@ -280,8 +307,7 @@ static int __init mod_init(void)
 		pci_write_config_byte(dev,
 		                      fwh_dec_en1_off,
 		                      fwh_dec_en1_val | FWH_F8_EN_MASK);
-	if (!(bios_cntl_val &
-	      (BIOS_CNTL_LOCK_ENABLE_MASK|BIOS_CNTL_WRITE_ENABLE_MASK)))
+	if (!(bios_cntl_val & BIOS_CNTL_WRITE_ENABLE_MASK))
 		pci_write_config_byte(dev,
 		                      bios_cntl_off,
 		                      bios_cntl_val | BIOS_CNTL_WRITE_ENABLE_MASK);
@@ -315,6 +341,8 @@ static int __init mod_init(void)
 		goto out;
 	}
 
+fwh_done:
+
 	err = -ENOMEM;
 	mem = ioremap(INTEL_RNG_ADDR, INTEL_RNG_ADDR_LEN);
 	if (!mem)