From:   Jithu Joseph <jithu.joseph@intel.com>
To:     hdegoede@redhat.com, markgross@kernel.org
Cc:     tglx@linutronix.de, mingo@redhat.com, bp@alien8.de,
        dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com,
        gregkh@linuxfoundation.org, rostedt@goodmis.org,
        jithu.joseph@intel.com, ashok.raj@intel.com, tony.luck@intel.com,
        linux-kernel@vger.kernel.org, platform-driver-x86@vger.kernel.org,
        patches@lists.linux.dev, ravi.v.shankar@intel.com,
        thiago.macieira@intel.com, athenas.jimenez.gonzalez@intel.com,
        sohil.mehta@intel.com
Subject: [PATCH v3 4/8] platform/x86/intel/ifs: Introduce Array Scan test to IFS
Date:   Tue, 28 Feb 2023 17:59:38 -0800
Message-Id: <20230301015942.462799-5-jithu.joseph@intel.com>
In-Reply-To: <20230301015942.462799-1-jithu.joseph@intel.com>
References: <20230214234426.344960-1-jithu.joseph@intel.com>
 <20230301015942.462799-1-jithu.joseph@intel.com>
MIME-Version: 1.0
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Array BIST is a new type of core test introduced under the Intel Infield
Scan (IFS) suite of tests.

Emerald Rapids (EMR) is the first CPU to support Array BIST.
Array BIST performs tests on some portions of the core logic such as
caches and register files. These are different portions of the silicon
compared to the parts tested by the first test type
i.e Scan at Field (SAF).

Make changes in the device driver init flow to register this new test
type with the device driver framework. Each test will have its own
sysfs directory (intel_ifs_0 , intel_ifs_1) under misc hierarchy to
accommodate for the differences in test type and how they are initiated.

Upcoming patches will add actual support.

Signed-off-by: Jithu Joseph <jithu.joseph@intel.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
---
 drivers/platform/x86/intel/ifs/ifs.h  |  3 +
 drivers/platform/x86/intel/ifs/core.c | 85 +++++++++++++++++++--------
 2 files changed, 62 insertions(+), 26 deletions(-)

diff --git a/drivers/platform/x86/intel/ifs/ifs.h b/drivers/platform/x86/intel/ifs/ifs.h
index ab168ddf28f1..b8b956e29653 100644
--- a/drivers/platform/x86/intel/ifs/ifs.h
+++ b/drivers/platform/x86/intel/ifs/ifs.h
@@ -137,6 +137,9 @@
 #define SCAN_TEST_PASS				1
 #define SCAN_TEST_FAIL				2
 
+#define IFS_TYPE_SAF			0
+#define IFS_TYPE_ARRAY_BIST		1
+
 /* MSR_SCAN_HASHES_STATUS bit fields */
 union ifs_scan_hashes_status {
 	u64	data;
diff --git a/drivers/platform/x86/intel/ifs/core.c b/drivers/platform/x86/intel/ifs/core.c
index 62c44dbae757..2237aaba7078 100644
--- a/drivers/platform/x86/intel/ifs/core.c
+++ b/drivers/platform/x86/intel/ifs/core.c
@@ -16,6 +16,7 @@
 
 static const struct x86_cpu_id ifs_cpu_ids[] __initconst = {
 	X86_MATCH(SAPPHIRERAPIDS_X),
+	X86_MATCH(EMERALDRAPIDS_X),
 	{}
 };
 MODULE_DEVICE_TABLE(x86cpu, ifs_cpu_ids);
@@ -24,23 +25,51 @@ ATTRIBUTE_GROUPS(plat_ifs);
 
 bool *ifs_pkg_auth;
 
-static struct ifs_device ifs_device = {
-	.ro_data = {
-		.integrity_cap_bit = MSR_INTEGRITY_CAPS_PERIODIC_BIST_BIT,
-		.test_num = 0,
+static struct ifs_device ifs_devices[] = {
+	[IFS_TYPE_SAF] = {
+		.ro_data = {
+			.integrity_cap_bit = MSR_INTEGRITY_CAPS_PERIODIC_BIST_BIT,
+			.test_num = IFS_TYPE_SAF,
+		},
+		.misc = {
+			.name = "intel_ifs_0",
+			.minor = MISC_DYNAMIC_MINOR,
+			.groups = plat_ifs_groups,
+		},
 	},
-	.misc = {
-		.name = "intel_ifs_0",
-		.minor = MISC_DYNAMIC_MINOR,
-		.groups = plat_ifs_groups,
+	[IFS_TYPE_ARRAY_BIST] = {
+		.ro_data = {
+			.integrity_cap_bit = MSR_INTEGRITY_CAPS_ARRAY_BIST_BIT,
+			.test_num = IFS_TYPE_ARRAY_BIST,
+		},
+		.misc = {
+			.name = "intel_ifs_1",
+			.minor = MISC_DYNAMIC_MINOR,
+		},
 	},
 };
 
+#define IFS_NUMTESTS ARRAY_SIZE(ifs_devices)
+
+static void ifs_cleanup(void)
+{
+	int i;
+
+	for (i = 0; i < IFS_NUMTESTS; i++) {
+		if (ifs_devices[i].misc.this_device) {
+			misc_deregister(&ifs_devices[i].misc);
+			kfree(ifs_devices[i].rw_data);
+		}
+	}
+	kfree(ifs_pkg_auth);
+}
+
 static int __init ifs_init(void)
 {
 	const struct x86_cpu_id *m;
 	struct ifs_data *ifsd;
 	u64 msrval;
+	int i, ret;
 
 	m = x86_match_cpu(ifs_cpu_ids);
 	if (!m)
@@ -55,35 +84,39 @@ static int __init ifs_init(void)
 	if (rdmsrl_safe(MSR_INTEGRITY_CAPS, &msrval))
 		return -ENODEV;
 
-	if (!(msrval & BIT(ifs_device.ro_data.integrity_cap_bit)))
-		return -ENODEV;
-
 	ifs_pkg_auth = kmalloc_array(topology_max_packages(), sizeof(bool), GFP_KERNEL);
 	if (!ifs_pkg_auth)
 		return -ENOMEM;
 
-	ifsd = kzalloc(sizeof(*ifsd), GFP_KERNEL);
-	if (!ifsd)
-		return -ENOMEM;
-
-	ifsd->ro_info = &ifs_device.ro_data;
-	ifs_device.rw_data = ifsd;
-
-	if (misc_register(&ifs_device.misc)) {
-		kfree(ifsd);
-		kfree(ifs_pkg_auth);
-		return -ENODEV;
+	for (i = 0; i < IFS_NUMTESTS; i++) {
+		ifsd = NULL;
+		if (!(msrval & BIT(ifs_devices[i].ro_data.integrity_cap_bit)))
+			continue;
+
+		ifsd = kzalloc(sizeof(*ifsd), GFP_KERNEL);
+		if (!ifsd) {
+			ret = -ENOMEM;
+			goto err_exit;
+		}
+		ifsd->ro_info = &ifs_devices[i].ro_data;
+		ifs_devices[i].rw_data = ifsd;
+
+		if (misc_register(&ifs_devices[i].misc)) {
+			ret = -ENODEV;
+			kfree(ifsd);
+			goto err_exit;
+		}
 	}
-
 	return 0;
 
+err_exit:
+	ifs_cleanup();
+	return ret;
 }
 
 static void __exit ifs_exit(void)
 {
-	misc_deregister(&ifs_device.misc);
-	kfree(ifs_device.rw_data);
-	kfree(ifs_pkg_auth);
+	ifs_cleanup();
 }
 
 module_init(ifs_init);
-- 
2.25.1