platform/x86/amd/hsmp: create plat specific struct

Having a separate platform device structure helps in future, to
contain platform specific variables and other data.

Also, define macros for dev nodes

Signed-off-by: Suma Hegde <suma.hegde@amd.com>
Reviewed-by: Naveen Krishna Chatradhi <nchatrad@amd.com>
Link: https://lore.kernel.org/r/20231010120310.3464066-1-suma.hegde@amd.com
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

Author: sumachidanand

drivers/platform/x86/amd/hsmp.c

@@ -47,9 +47,22 @@
 #define HSMP_INDEX_REG		0xc4
 #define HSMP_DATA_REG		0xc8
 
-static struct semaphore *hsmp_sem;
+#define HSMP_CDEV_NAME		"hsmp_cdev"
+#define HSMP_DEVNODE_NAME	"hsmp"
 
-static struct miscdevice hsmp_device;
+struct hsmp_socket {
+	struct semaphore hsmp_sem;
+	u16 sock_ind;
+};
+
+struct hsmp_plat_device {
+	struct miscdevice hsmp_device;
+	struct hsmp_socket *sock;
+	struct device *dev;
+	u16 num_sockets;
+};
+
+static struct hsmp_plat_device plat_dev;
 
 static int amd_hsmp_rdwr(struct pci_dev *root, u32 address,
 			 u32 *value, bool write)
@@ -188,6 +201,7 @@ static int validate_message(struct hsmp_message *msg)
 
 int hsmp_send_message(struct hsmp_message *msg)
 {
+	struct hsmp_socket *sock = &plat_dev.sock[msg->sock_ind];
 	struct amd_northbridge *nb;
 	int ret;
 
@@ -208,14 +222,13 @@ int hsmp_send_message(struct hsmp_message *msg)
 	 * In SMP system timeout of 100 millisecs should
 	 * be enough for the previous thread to finish the operation
 	 */
-	ret = down_timeout(&hsmp_sem[msg->sock_ind],
-			   msecs_to_jiffies(HSMP_MSG_TIMEOUT));
+	ret = down_timeout(&sock->hsmp_sem, msecs_to_jiffies(HSMP_MSG_TIMEOUT));
 	if (ret < 0)
 		return ret;
 
 	ret = __hsmp_send_message(nb->root, msg);
 
-	up(&hsmp_sem[msg->sock_ind]);
+	up(&sock->hsmp_sem);
 
 	return ret;
 }
@@ -321,28 +334,31 @@ static int hsmp_pltdrv_probe(struct platform_device *pdev)
 {
 	int i;
 
-	hsmp_sem = devm_kzalloc(&pdev->dev,
-				(amd_nb_num() * sizeof(struct semaphore)),
-				GFP_KERNEL);
-	if (!hsmp_sem)
+	plat_dev.sock = devm_kzalloc(&pdev->dev,
+				     (plat_dev.num_sockets * sizeof(struct hsmp_socket)),
+				     GFP_KERNEL);
+	if (!plat_dev.sock)
 		return -ENOMEM;
+	plat_dev.dev = &pdev->dev;
 
-	for (i = 0; i < amd_nb_num(); i++)
-		sema_init(&hsmp_sem[i], 1);
+	for (i = 0; i < plat_dev.num_sockets; i++) {
+		sema_init(&plat_dev.sock[i].hsmp_sem, 1);
+		plat_dev.sock[i].sock_ind = i;
+	}
 
-	hsmp_device.name	= "hsmp_cdev";
-	hsmp_device.minor	= MISC_DYNAMIC_MINOR;
-	hsmp_device.fops	= &hsmp_fops;
-	hsmp_device.parent	= &pdev->dev;
-	hsmp_device.nodename	= "hsmp";
-	hsmp_device.mode	= 0644;
+	plat_dev.hsmp_device.name	= HSMP_CDEV_NAME;
+	plat_dev.hsmp_device.minor	= MISC_DYNAMIC_MINOR;
+	plat_dev.hsmp_device.fops	= &hsmp_fops;
+	plat_dev.hsmp_device.parent	= &pdev->dev;
+	plat_dev.hsmp_device.nodename	= HSMP_DEVNODE_NAME;
+	plat_dev.hsmp_device.mode	= 0644;
 
-	return misc_register(&hsmp_device);
+	return misc_register(&plat_dev.hsmp_device);
 }
 
 static void hsmp_pltdrv_remove(struct platform_device *pdev)
 {
-	misc_deregister(&hsmp_device);
+	misc_deregister(&plat_dev.hsmp_device);
 }
 
 static struct platform_driver amd_hsmp_driver = {
@@ -358,7 +374,6 @@ static struct platform_device *amd_hsmp_platdev;
 static int __init hsmp_plt_init(void)
 {
 	int ret = -ENODEV;
-	u16 num_sockets;
 	int i;
 
 	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD || boot_cpu_data.x86 < 0x19) {
@@ -371,12 +386,12 @@ static int __init hsmp_plt_init(void)
 	 * amd_nb_num() returns number of SMN/DF interfaces present in the system
 	 * if we have N SMN/DF interfaces that ideally means N sockets
 	 */
-	num_sockets = amd_nb_num();
-	if (num_sockets == 0)
+	plat_dev.num_sockets = amd_nb_num();
+	if (plat_dev.num_sockets == 0)
 		return ret;
 
 	/* Test the hsmp interface on each socket */
-	for (i = 0; i < num_sockets; i++) {
+	for (i = 0; i < plat_dev.num_sockets; i++) {
 		ret = hsmp_test(i, 0xDEADBEEF);
 		if (ret) {
 			pr_err("HSMP is not supported on Fam:%x model:%x\n",