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From:   LeoLiu-oc <LeoLiu-oc@zhaoxin.com>
To:     <olivia@selenic.com>, <herbert@gondor.apana.org.au>,
        <jiajie.ho@starfivetech.com>, <conor.dooley@microchip.com>,
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CC:     <leoliu@zhaoxin.com>, <CobeChen@zhaoxin.com>,
        <YunShen@zhaoxin.com>, <TonyWWang@zhaoxin.com>,
        leoliu-oc <leoliu-oc@zhaoxin.com>
Subject: [PATCH v2 1/2] hwrng: via-rng: convert to x86_cpu_id probing
Date:   Mon, 31 Jul 2023 16:45:14 +0800
Message-ID: <20230731084515.2057375-2-LeoLiu-oc@zhaoxin.com>
In-Reply-To: <20230731084515.2057375-1-LeoLiu-oc@zhaoxin.com>
References: <20230731084515.2057375-1-LeoLiu-oc@zhaoxin.com>
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From: leoliu-oc <leoliu-oc@zhaoxin.com>

With this, In addition to the Feature matching check,
add the CPU Vendor ID/Family check.

Signed-off-by: leoliu-oc <leoliu-oc@zhaoxin.com>
---
 drivers/char/hw_random/via-rng.c | 15 +++++++--------
 1 file changed, 7 insertions(+), 8 deletions(-)

diff --git a/drivers/char/hw_random/via-rng.c b/drivers/char/hw_random/via-rng.c
index a9a0a3b09c8b..d7feb3923819 100644
--- a/drivers/char/hw_random/via-rng.c
+++ b/drivers/char/hw_random/via-rng.c
@@ -135,7 +135,7 @@ 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))  || (c->x86 > 6)){
+	if (((c->x86 == 6) && (c->x86_model >= 0x0f))) {
 		if (!boot_cpu_has(X86_FEATURE_XSTORE_EN)) {
 			pr_err(PFX "can't enable hardware RNG "
 				"if XSTORE is not enabled\n");
@@ -191,12 +191,17 @@ static struct hwrng via_rng = {
 	.data_read	= via_rng_data_read,
 };
 
+static const struct x86_cpu_id via_rng_cpu_ids[] = {
+	X86_MATCH_VENDOR_FAM_FEATURE(CENTAUR, 6, X86_FEATURE_XSTORE, NULL),
+	{}
+};
+MODULE_DEVICE_TABLE(x86cpu, via_rng_cpu_ids);
 
 static int __init via_rng_mod_init(void)
 {
 	int err;
 
-	if (!boot_cpu_has(X86_FEATURE_XSTORE))
+	if (!x86_match_cpu(via_rng_cpu_ids))
 		return -ENODEV;
 
 	pr_info("VIA RNG detected\n");
@@ -217,11 +222,5 @@ static void __exit via_rng_mod_exit(void)
 }
 module_exit(via_rng_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");
-- 
2.34.1