diff options
Diffstat (limited to 'drivers/char/hw_random/via-rng.c')
| -rw-r--r-- | drivers/char/hw_random/via-rng.c | 43 |
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"); |
