RE: TPM driver changes to support multiple locality

["Agarwal, Lomesh" <lomesh.agarwal@intel.com>]

Below is the patch for TPM driver.
Comments/suggestions?

--- pristine-linux-2.6.18/drivers/char/tpm/tpm_tis.c	2006-09-19
20:42:06.000000000 -0700
+++ linux-2.6.18-xen/drivers/char/tpm/tpm_tis.c	2007-10-09
15:30:49.000000000 -0700
@@ -56,29 +56,36 @@
 
 enum tis_defaults {
 	TIS_MEM_BASE = 0xFED40000,
-	TIS_MEM_LEN = 0x5000,
+	TIS_MEM_LEN = 0x1000,
 	TIS_SHORT_TIMEOUT = 750,	/* ms */
 	TIS_LONG_TIMEOUT = 2000,	/* 2 sec */
 };
 
-#define	TPM_ACCESS(l)			(0x0000 | ((l) << 12))
-#define	TPM_INT_ENABLE(l)		(0x0008 | ((l) << 12))
-#define	TPM_INT_VECTOR(l)		(0x000C | ((l) << 12))
-#define	TPM_INT_STATUS(l)		(0x0010 | ((l) << 12))
-#define	TPM_INTF_CAPS(l)		(0x0014 | ((l) << 12))
-#define	TPM_STS(l)			(0x0018 | ((l) << 12))
-#define	TPM_DATA_FIFO(l)		(0x0024 | ((l) << 12))
+#define	TPM_ACCESS(l)			(0x0000)
+#define	TPM_INT_ENABLE(l)		(0x0008)
+#define	TPM_INT_VECTOR(l)		(0x000C)
+#define	TPM_INT_STATUS(l)		(0x0010)
+#define	TPM_INTF_CAPS(l)		(0x0014)
+#define	TPM_STS(l)			(0x0018)
+#define	TPM_DATA_FIFO(l)		(0x0024)
 
-#define	TPM_DID_VID(l)			(0x0F00 | ((l) << 12))
-#define	TPM_RID(l)			(0x0F04 | ((l) << 12))
+#define	TPM_DID_VID(l)			(0x0F00)
+#define	TPM_RID(l)			(0x0F04)
 
 static LIST_HEAD(tis_chips);
 static DEFINE_SPINLOCK(tis_lock);
 
 static int check_locality(struct tpm_chip *chip, int l)
 {
-	if ((ioread8(chip->vendor.iobase + TPM_ACCESS(l)) &
-	     (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID)) ==
+    unsigned char tpm_access;
+
+	tpm_access = ioread8(chip->vendor.iobase + TPM_ACCESS(l));
+
+    /* check if locality is closed */
+	if(tpm_access == 0xFF)
+        return -1;
+
+	if((tpm_access & (TPM_ACCESS_ACTIVE_LOCALITY |
TPM_ACCESS_VALID)) ==
 	    (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID))
 		return chip->vendor.locality = l;
 
@@ -251,10 +258,14 @@
 
 out:
 	tpm_tis_ready(chip);
-	release_locality(chip, chip->vendor.locality, 0);
+	release_locality(chip, chip->vendor.locality, 1);
 	return size;
 }
 
+static int locality = 0;
+module_param(locality, int, 0444);
+MODULE_PARM_DESC(locality, "TPM Locality To access");
+
 /*
  * If interrupts are used (signaled by an irq set in the vendor
structure)
  * tpm.c can skip polling for the data to be available as the interrupt
is
@@ -266,7 +277,7 @@
 	size_t count = 0;
 	u32 ordinal;
 
-	if (request_locality(chip, 0) < 0)
+	if (request_locality(chip, locality) < 0)
 		return -EBUSY;
 
 	status = tpm_tis_status(chip);
@@ -326,7 +337,7 @@
 	return len;
 out_err:
 	tpm_tis_ready(chip);
-	release_locality(chip, chip->vendor.locality, 0);
+	release_locality(chip, chip->vendor.locality, 1);
 	return rc;
 }
 
@@ -401,7 +412,10 @@
 {
 	struct tpm_chip *chip = (struct tpm_chip *) dev_id;
 	u32 interrupt;
-	int i;
+
+        /* check if interrupt is meant for this locality */
+        if(check_locality(chip, locality) < 0)
+                return IRQ_NONE;
 
 	interrupt = ioread32(chip->vendor.iobase +
 			     TPM_INT_STATUS(chip->vendor.locality));
@@ -411,10 +425,6 @@
 
 	if (interrupt & TPM_INTF_DATA_AVAIL_INT)
 		wake_up_interruptible(&chip->vendor.read_queue);
-	if (interrupt & TPM_INTF_LOCALITY_CHANGE_INT)
-		for (i = 0; i < 5; i++)
-			if (check_locality(chip, i) >= 0)
-				break;
 	if (interrupt &
 	    (TPM_INTF_LOCALITY_CHANGE_INT | TPM_INTF_STS_VALID_INT |
 	     TPM_INTF_CMD_READY_INT))
@@ -440,7 +450,7 @@
 	struct tpm_chip *chip;
 
 	if (!start)
-		start = TIS_MEM_BASE;
+		start = TIS_MEM_BASE | (locality << 12);
 	if (!len)
 		len = TIS_MEM_LEN;
 
@@ -490,8 +500,9 @@
 	if (intfcaps & TPM_INTF_DATA_AVAIL_INT)
 		dev_dbg(dev, "\tData Avail Int Support\n");
 
-	if (request_locality(chip, 0) != 0) {
-		rc = -ENODEV;
+	if (request_locality(chip, locality) < 0) {
+		rc = -EBUSY;
+		printk("failed request_locality\n");
 		goto out_err;
 	}
 
@@ -582,9 +593,11 @@
 
 	tpm_get_timeouts(chip);
 	tpm_continue_selftest(chip);
+	release_locality(chip, chip->vendor.locality, 1);
 
 	return 0;
 out_err:
+	release_locality(chip, chip->vendor.locality, 1);
 	if (chip->vendor.iobase)
 		iounmap(chip->vendor.iobase);
 	tpm_remove_hardware(chip->dev);
@@ -636,7 +649,7 @@
 MODULE_PARM_DESC(hid, "Set additional specific HID for this driver to
probe");
 
 static struct device_driver tis_drv = {
-	.name = "tpm_tis",
+	.name = "",
 	.bus = &platform_bus_type,
 	.owner = THIS_MODULE,
 	.suspend = tpm_pm_suspend,
@@ -648,19 +661,34 @@
 static int force;
 module_param(force, bool, 0444);
 MODULE_PARM_DESC(force, "Force device probe rather than using ACPI
entry");
+
+static char *devname = NULL;
+
 static int __init init_tis(void)
 {
+#define DEVNAME_SIZE 10
+
 	int rc;
 
+	if ((locality < 0) || (locality > 4)) {
+		return PTR_ERR(pdev);
+	}
+
 	if (force) {
+		devname = kmalloc(DEVNAME_SIZE, GFP_KERNEL);
+        	scnprintf(devname, DEVNAME_SIZE, "%s%d", "tpm_tis",
locality);
+
+		tis_drv.name = devname;
 		rc = driver_register(&tis_drv);
 		if (rc < 0)
 			return rc;
-		if
(IS_ERR(pdev=platform_device_register_simple("tpm_tis", -1, NULL, 0)))
+
+		if (IS_ERR(pdev=platform_device_register_simple(devname,
-1, NULL, 0)))
 			return PTR_ERR(pdev);
 		if((rc=tpm_tis_init(&pdev->dev, 0, 0)) != 0) {
 			platform_device_unregister(pdev);
 			driver_unregister(&tis_drv);
+			kfree(devname);
 		}
 		return rc;
 	}
@@ -692,7 +720,9 @@
 	if (force) {
 		platform_device_unregister(pdev);
 		driver_unregister(&tis_drv);
-	} else
+		kfree(devname);
+	}
+	else 
 		pnp_unregister_driver(&tis_pnp_driver);
 }


-----Original Message-----
From: Valdis.Kletnieks@vt.edu [mailto:Valdis.Kletnieks@vt.edu] 
Sent: Wednesday, October 10, 2007 12:46 PM
To: Agarwal, Lomesh
Cc: linux-kernel@vger.kernel.org
Subject: Re: TPM driver changes to support multiple locality

On Tue, 09 Oct 2007 15:51:11 PDT, "Agarwal, Lomesh" said:
> Current TPM driver supports only locality 0. I am planning to add
> support so that it can access any locality. Locality parameter will be
> passed as parameter. Will this change be acceptable? If yes then I
will
> modify the driver and send the patch.

Make sure you extend the API in such a way that older userspace programs
that don't pass the new locality parameter still work correctly.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/