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path: root/drivers/char/hw_random/via-rng.c
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Diffstat (limited to 'drivers/char/hw_random/via-rng.c')
-rw-r--r--drivers/char/hw_random/via-rng.c43
1 files changed, 23 insertions, 20 deletions
diff --git a/drivers/char/hw_random/via-rng.c b/drivers/char/hw_random/via-rng.c
index d0387a84eec1..a9a0a3b09c8b 100644
--- a/drivers/char/hw_random/via-rng.c
+++ b/drivers/char/hw_random/via-rng.c
@@ -29,10 +29,11 @@
#include <linux/kernel.h>
#include <linux/hw_random.h>
#include <linux/delay.h>
+#include <asm/cpu_device_id.h>
#include <asm/io.h>
#include <asm/msr.h>
#include <asm/cpufeature.h>
-#include <asm/i387.h>
+#include <asm/fpu/api.h>
@@ -69,21 +70,17 @@ enum {
* until we have 4 bytes, thus returning a u32 at a time,
* instead of the current u8-at-a-time.
*
- * Padlock instructions can generate a spurious DNA fault, so
- * we have to call them in the context of irq_ts_save/restore()
+ * Padlock instructions can generate a spurious DNA fault, but the
+ * kernel doesn't use CR0.TS, so this doesn't matter.
*/
static inline u32 xstore(u32 *addr, u32 edx_in)
{
u32 eax_out;
- int ts_state;
-
- ts_state = irq_ts_save();
asm(".byte 0x0F,0xA7,0xC0 /* xstore %%edi (addr=%0) */"
: "=m" (*addr), "=a" (eax_out), "+d" (edx_in), "+D" (addr));
- irq_ts_restore(ts_state);
return eax_out;
}
@@ -138,9 +135,9 @@ static int via_rng_init(struct hwrng *rng)
* is always enabled if CPUID rng_en is set. There is no
* RNG configuration like it used to be the case in this
* register */
- if ((c->x86 == 6) && (c->x86_model >= 0x0f)) {
- if (!cpu_has_xstore_enabled) {
- printk(KERN_ERR PFX "can't enable hardware RNG "
+ if (((c->x86 == 6) && (c->x86_model >= 0x0f)) || (c->x86 > 6)){
+ if (!boot_cpu_has(X86_FEATURE_XSTORE_EN)) {
+ pr_err(PFX "can't enable hardware RNG "
"if XSTORE is not enabled\n");
return -ENODEV;
}
@@ -148,7 +145,7 @@ static int via_rng_init(struct hwrng *rng)
}
/* Control the RNG via MSR. Tread lightly and pay very close
- * close attention to values written, as the reserved fields
+ * attention to values written, as the reserved fields
* are documented to be "undefined and unpredictable"; but it
* does not say to write them as zero, so I make a guess that
* we restore the values we find in the register.
@@ -165,7 +162,7 @@ static int via_rng_init(struct hwrng *rng)
/* Enable secondary noise source on CPUs where it is present. */
/* Nehemiah stepping 8 and higher */
- if ((c->x86_model == 9) && (c->x86_mask > 7))
+ if ((c->x86_model == 9) && (c->x86_stepping > 7))
lo |= VIA_NOISESRC2;
/* Esther */
@@ -179,7 +176,7 @@ static int via_rng_init(struct hwrng *rng)
unneeded */
rdmsr(MSR_VIA_RNG, lo, hi);
if ((lo & VIA_RNG_ENABLE) == 0) {
- printk(KERN_ERR PFX "cannot enable VIA C3 RNG, aborting\n");
+ pr_err(PFX "cannot enable VIA C3 RNG, aborting\n");
return -ENODEV;
}
@@ -195,30 +192,36 @@ static struct hwrng via_rng = {
};
-static int __init mod_init(void)
+static int __init via_rng_mod_init(void)
{
int err;
- if (!cpu_has_xstore)
+ if (!boot_cpu_has(X86_FEATURE_XSTORE))
return -ENODEV;
- printk(KERN_INFO "VIA RNG detected\n");
+
+ pr_info("VIA RNG detected\n");
err = hwrng_register(&via_rng);
if (err) {
- printk(KERN_ERR PFX "RNG registering failed (%d)\n",
+ pr_err(PFX "RNG registering failed (%d)\n",
err);
goto out;
}
out:
return err;
}
+module_init(via_rng_mod_init);
-static void __exit mod_exit(void)
+static void __exit via_rng_mod_exit(void)
{
hwrng_unregister(&via_rng);
}
+module_exit(via_rng_mod_exit);
-module_init(mod_init);
-module_exit(mod_exit);
+static struct x86_cpu_id __maybe_unused via_rng_cpu_id[] = {
+ X86_MATCH_FEATURE(X86_FEATURE_XSTORE, NULL),
+ {}
+};
+MODULE_DEVICE_TABLE(x86cpu, via_rng_cpu_id);
MODULE_DESCRIPTION("H/W RNG driver for VIA CPU with PadLock");
MODULE_LICENSE("GPL");