Revert "tpm/tpm_crb: open code the crb_init into acpi_add"
[cascardo/linux.git] / drivers / char / tpm / tpm_crb.c
index 733cd0e..2d1669c 100644 (file)
@@ -19,7 +19,6 @@
 #include <linux/highmem.h>
 #include <linux/rculist.h>
 #include <linux/module.h>
-#include <linux/platform_device.h>
 #include "tpm.h"
 
 #define ACPI_SIG_TPM2 "TPM2"
@@ -34,14 +33,14 @@ enum crb_defaults {
        CRB_ACPI_START_INDEX = 1,
 };
 
-enum crb_ca_request {
-       CRB_CA_REQ_GO_IDLE      = BIT(0),
-       CRB_CA_REQ_CMD_READY    = BIT(1),
+enum crb_ctrl_req {
+       CRB_CTRL_REQ_CMD_READY  = BIT(0),
+       CRB_CTRL_REQ_GO_IDLE    = BIT(1),
 };
 
-enum crb_ca_status {
-       CRB_CA_STS_ERROR        = BIT(0),
-       CRB_CA_STS_TPM_IDLE     = BIT(1),
+enum crb_ctrl_sts {
+       CRB_CTRL_STS_ERROR      = BIT(0),
+       CRB_CTRL_STS_TPM_IDLE   = BIT(1),
 };
 
 enum crb_start {
@@ -67,7 +66,7 @@ struct crb_control_area {
 } __packed;
 
 enum crb_status {
-       CRB_STS_COMPLETE        = BIT(0),
+       CRB_DRV_STS_COMPLETE    = BIT(0),
 };
 
 enum crb_flags {
@@ -81,32 +80,102 @@ struct crb_priv {
        struct crb_control_area __iomem *cca;
        u8 __iomem *cmd;
        u8 __iomem *rsp;
+       u32 cmd_size;
 };
 
+/**
+ * crb_go_idle - request tpm crb device to go the idle state
+ *
+ * @dev:  crb device
+ * @priv: crb private data
+ *
+ * Write CRB_CTRL_REQ_GO_IDLE to TPM_CRB_CTRL_REQ
+ * The device should respond within TIMEOUT_C by clearing the bit.
+ * Anyhow, we do not wait here as a consequent CMD_READY request
+ * will be handled correctly even if idle was not completed.
+ *
+ * The function does nothing for devices with ACPI-start method.
+ *
+ * Return: 0 always
+ */
+static int __maybe_unused crb_go_idle(struct device *dev, struct crb_priv *priv)
+{
+       if (priv->flags & CRB_FL_ACPI_START)
+               return 0;
+
+       iowrite32(CRB_CTRL_REQ_GO_IDLE, &priv->cca->req);
+       /* we don't really care when this settles */
+
+       return 0;
+}
+
+/**
+ * crb_cmd_ready - request tpm crb device to enter ready state
+ *
+ * @dev:  crb device
+ * @priv: crb private data
+ *
+ * Write CRB_CTRL_REQ_CMD_READY to TPM_CRB_CTRL_REQ
+ * and poll till the device acknowledge it by clearing the bit.
+ * The device should respond within TIMEOUT_C.
+ *
+ * The function does nothing for devices with ACPI-start method
+ *
+ * Return: 0 on success -ETIME on timeout;
+ */
+static int __maybe_unused crb_cmd_ready(struct device *dev,
+                                       struct crb_priv *priv)
+{
+       ktime_t stop, start;
+
+       if (priv->flags & CRB_FL_ACPI_START)
+               return 0;
+
+       iowrite32(CRB_CTRL_REQ_CMD_READY, &priv->cca->req);
+
+       start = ktime_get();
+       stop = ktime_add(start, ms_to_ktime(TPM2_TIMEOUT_C));
+       do {
+               if (!(ioread32(&priv->cca->req) & CRB_CTRL_REQ_CMD_READY)) {
+                       dev_dbg(dev, "cmdReady in %lld usecs\n",
+                               ktime_to_us(ktime_sub(ktime_get(), start)));
+                       return 0;
+               }
+               usleep_range(50, 100);
+       } while (ktime_before(ktime_get(), stop));
+
+       if (ioread32(&priv->cca->req) & CRB_CTRL_REQ_CMD_READY) {
+               dev_warn(dev, "cmdReady timed out\n");
+               return -ETIME;
+       }
+
+       return 0;
+}
+
 static SIMPLE_DEV_PM_OPS(crb_pm, tpm_pm_suspend, tpm_pm_resume);
 
 static u8 crb_status(struct tpm_chip *chip)
 {
-       struct crb_priv *priv = chip->vendor.priv;
+       struct crb_priv *priv = dev_get_drvdata(&chip->dev);
        u8 sts = 0;
 
        if ((ioread32(&priv->cca->start) & CRB_START_INVOKE) !=
            CRB_START_INVOKE)
-               sts |= CRB_STS_COMPLETE;
+               sts |= CRB_DRV_STS_COMPLETE;
 
        return sts;
 }
 
 static int crb_recv(struct tpm_chip *chip, u8 *buf, size_t count)
 {
-       struct crb_priv *priv = chip->vendor.priv;
+       struct crb_priv *priv = dev_get_drvdata(&chip->dev);
        unsigned int expected;
 
        /* sanity check */
        if (count < 6)
                return -EIO;
 
-       if (ioread32(&priv->cca->sts) & CRB_CA_STS_ERROR)
+       if (ioread32(&priv->cca->sts) & CRB_CTRL_STS_ERROR)
                return -EIO;
 
        memcpy_fromio(buf, priv->rsp, 6);
@@ -139,14 +208,17 @@ static int crb_do_acpi_start(struct tpm_chip *chip)
 
 static int crb_send(struct tpm_chip *chip, u8 *buf, size_t len)
 {
-       struct crb_priv *priv = chip->vendor.priv;
+       struct crb_priv *priv = dev_get_drvdata(&chip->dev);
        int rc = 0;
 
-       if (len > ioread32(&priv->cca->cmd_size)) {
-               dev_err(&chip->dev,
-                       "invalid command count value %x %zx\n",
-                       (unsigned int) len,
-                       (size_t) ioread32(&priv->cca->cmd_size));
+       /* Zero the cancel register so that the next command will not get
+        * canceled.
+        */
+       iowrite32(0, &priv->cca->cancel);
+
+       if (len > priv->cmd_size) {
+               dev_err(&chip->dev, "invalid command count value %zd %d\n",
+                       len, priv->cmd_size);
                return -E2BIG;
        }
 
@@ -156,7 +228,7 @@ static int crb_send(struct tpm_chip *chip, u8 *buf, size_t len)
        wmb();
 
        if (priv->flags & CRB_FL_CRB_START)
-               iowrite32(cpu_to_le32(CRB_START_INVOKE), &priv->cca->start);
+               iowrite32(CRB_START_INVOKE, &priv->cca->start);
 
        if (priv->flags & CRB_FL_ACPI_START)
                rc = crb_do_acpi_start(chip);
@@ -166,58 +238,45 @@ static int crb_send(struct tpm_chip *chip, u8 *buf, size_t len)
 
 static void crb_cancel(struct tpm_chip *chip)
 {
-       struct crb_priv *priv = chip->vendor.priv;
+       struct crb_priv *priv = dev_get_drvdata(&chip->dev);
 
-       iowrite32(cpu_to_le32(CRB_CANCEL_INVOKE), &priv->cca->cancel);
-
-       /* Make sure that cmd is populated before issuing cancel. */
-       wmb();
+       iowrite32(CRB_CANCEL_INVOKE, &priv->cca->cancel);
 
        if ((priv->flags & CRB_FL_ACPI_START) && crb_do_acpi_start(chip))
                dev_err(&chip->dev, "ACPI Start failed\n");
-
-       iowrite32(0, &priv->cca->cancel);
 }
 
 static bool crb_req_canceled(struct tpm_chip *chip, u8 status)
 {
-       struct crb_priv *priv = chip->vendor.priv;
+       struct crb_priv *priv = dev_get_drvdata(&chip->dev);
        u32 cancel = ioread32(&priv->cca->cancel);
 
        return (cancel & CRB_CANCEL_INVOKE) == CRB_CANCEL_INVOKE;
 }
 
 static const struct tpm_class_ops tpm_crb = {
+       .flags = TPM_OPS_AUTO_STARTUP,
        .status = crb_status,
        .recv = crb_recv,
        .send = crb_send,
        .cancel = crb_cancel,
        .req_canceled = crb_req_canceled,
-       .req_complete_mask = CRB_STS_COMPLETE,
-       .req_complete_val = CRB_STS_COMPLETE,
+       .req_complete_mask = CRB_DRV_STS_COMPLETE,
+       .req_complete_val = CRB_DRV_STS_COMPLETE,
 };
 
 static int crb_init(struct acpi_device *device, struct crb_priv *priv)
 {
        struct tpm_chip *chip;
-       int rc;
 
        chip = tpmm_chip_alloc(&device->dev, &tpm_crb);
        if (IS_ERR(chip))
                return PTR_ERR(chip);
 
-       chip->vendor.priv = priv;
+       dev_set_drvdata(&chip->dev, priv);
        chip->acpi_dev_handle = device->handle;
        chip->flags = TPM_CHIP_FLAG_TPM2;
 
-       rc = tpm_get_timeouts(chip);
-       if (rc)
-               return rc;
-
-       rc = tpm2_do_selftest(chip);
-       if (rc)
-               return rc;
-
        return tpm_chip_register(chip);
 }
 
@@ -245,7 +304,7 @@ static void __iomem *crb_map_res(struct device *dev, struct crb_priv *priv,
 
        /* Detect a 64 bit address on a 32 bit system */
        if (start != new_res.start)
-               return ERR_PTR(-EINVAL);
+               return (void __iomem *) ERR_PTR(-EINVAL);
 
        if (!resource_contains(io_res, &new_res))
                return devm_ioremap_resource(dev, &new_res);
@@ -259,7 +318,11 @@ static int crb_map_io(struct acpi_device *device, struct crb_priv *priv,
        struct list_head resources;
        struct resource io_res;
        struct device *dev = &device->dev;
-       u64 pa;
+       u32 pa_high, pa_low;
+       u64 cmd_pa;
+       u32 cmd_size;
+       u64 rsp_pa;
+       u32 rsp_size;
        int ret;
 
        INIT_LIST_HEAD(&resources);
@@ -270,8 +333,7 @@ static int crb_map_io(struct acpi_device *device, struct crb_priv *priv,
        acpi_dev_free_resource_list(&resources);
 
        if (resource_type(&io_res) != IORESOURCE_MEM) {
-               dev_err(dev,
-                       FW_BUG "TPM2 ACPI table does not define a memory resource\n");
+               dev_err(dev, FW_BUG "TPM2 ACPI table does not define a memory resource\n");
                return -EINVAL;
        }
 
@@ -280,22 +342,59 @@ static int crb_map_io(struct acpi_device *device, struct crb_priv *priv,
                return PTR_ERR(priv->iobase);
 
        priv->cca = crb_map_res(dev, priv, &io_res, buf->control_address,
-                               0x1000);
+                               sizeof(struct crb_control_area));
        if (IS_ERR(priv->cca))
                return PTR_ERR(priv->cca);
 
-       pa = ((u64) ioread32(&priv->cca->cmd_pa_high) << 32) |
-             (u64) ioread32(&priv->cca->cmd_pa_low);
-       priv->cmd = crb_map_res(dev, priv, &io_res, pa,
-                               ioread32(&priv->cca->cmd_size));
-       if (IS_ERR(priv->cmd))
-               return PTR_ERR(priv->cmd);
-
-       memcpy_fromio(&pa, &priv->cca->rsp_pa, 8);
-       pa = le64_to_cpu(pa);
-       priv->rsp = crb_map_res(dev, priv, &io_res, pa,
-                               ioread32(&priv->cca->rsp_size));
-       return PTR_ERR_OR_ZERO(priv->rsp);
+       /*
+        * PTT HW bug w/a: wake up the device to access
+        * possibly not retained registers.
+        */
+       ret = crb_cmd_ready(dev, priv);
+       if (ret)
+               return ret;
+
+       pa_high = ioread32(&priv->cca->cmd_pa_high);
+       pa_low  = ioread32(&priv->cca->cmd_pa_low);
+       cmd_pa = ((u64)pa_high << 32) | pa_low;
+       cmd_size = ioread32(&priv->cca->cmd_size);
+
+       dev_dbg(dev, "cmd_hi = %X cmd_low = %X cmd_size %X\n",
+               pa_high, pa_low, cmd_size);
+
+       priv->cmd = crb_map_res(dev, priv, &io_res, cmd_pa, cmd_size);
+       if (IS_ERR(priv->cmd)) {
+               ret = PTR_ERR(priv->cmd);
+               goto out;
+       }
+
+       memcpy_fromio(&rsp_pa, &priv->cca->rsp_pa, 8);
+       rsp_pa = le64_to_cpu(rsp_pa);
+       rsp_size = ioread32(&priv->cca->rsp_size);
+
+       if (cmd_pa != rsp_pa) {
+               priv->rsp = crb_map_res(dev, priv, &io_res, rsp_pa, rsp_size);
+               ret = PTR_ERR_OR_ZERO(priv->rsp);
+               goto out;
+       }
+
+       /* According to the PTP specification, overlapping command and response
+        * buffer sizes must be identical.
+        */
+       if (cmd_size != rsp_size) {
+               dev_err(dev, FW_BUG "overlapping command and response buffer sizes are not identical");
+               ret = -EINVAL;
+               goto out;
+       }
+
+       priv->cmd_size = cmd_size;
+
+       priv->rsp = priv->cmd;
+
+out:
+       crb_go_idle(dev, priv);
+
+       return ret;
 }
 
 static int crb_acpi_add(struct acpi_device *device)
@@ -339,7 +438,15 @@ static int crb_acpi_add(struct acpi_device *device)
        if (rc)
                return rc;
 
-       return crb_init(device, priv);
+       rc  = crb_cmd_ready(dev, priv);
+       if (rc)
+               return rc;
+
+       rc = crb_init(device, priv);
+       if (rc)
+               crb_go_idle(dev, priv);
+
+       return rc;
 }
 
 static int crb_acpi_remove(struct acpi_device *device)