[PATCH v3 1/3] tpm_crb: map locality registers

From: Jarkko Sakkinen
Date: Wed Feb 08 2017 - 06:16:12 EST


In order to provide access to locality registers, this commits adds
mapping of the head of the CRB registers, which are located right
before the control area.

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>
---
drivers/char/tpm/tpm_crb.c | 89 +++++++++++++++++++++++++++++-----------------
1 file changed, 57 insertions(+), 32 deletions(-)

diff --git a/drivers/char/tpm/tpm_crb.c b/drivers/char/tpm/tpm_crb.c
index 717b6b4..80b9759 100644
--- a/drivers/char/tpm/tpm_crb.c
+++ b/drivers/char/tpm/tpm_crb.c
@@ -52,18 +52,28 @@ enum crb_cancel {
CRB_CANCEL_INVOKE = BIT(0),
};

-struct crb_control_area {
- u32 req;
- u32 sts;
- u32 cancel;
- u32 start;
- u32 int_enable;
- u32 int_sts;
- u32 cmd_size;
- u32 cmd_pa_low;
- u32 cmd_pa_high;
- u32 rsp_size;
- u64 rsp_pa;
+struct crb_regs_head {
+ u32 loc_state;
+ u32 reserved1;
+ u32 loc_ctrl;
+ u32 loc_sts;
+ u8 reserved2[32];
+ u64 intf_id;
+ u64 ctrl_ext;
+} __packed;
+
+struct crb_regs_tail {
+ u32 ctrl_req;
+ u32 ctrl_sts;
+ u32 ctrl_cancel;
+ u32 ctrl_start;
+ u32 ctrl_int_enable;
+ u32 ctrl_int_sts;
+ u32 ctrl_cmd_size;
+ u32 ctrl_cmd_pa_low;
+ u32 ctrl_cmd_pa_high;
+ u32 ctrl_rsp_size;
+ u64 ctrl_rsp_pa;
} __packed;

enum crb_status {
@@ -78,7 +88,8 @@ enum crb_flags {
struct crb_priv {
unsigned int flags;
void __iomem *iobase;
- struct crb_control_area __iomem *cca;
+ struct crb_regs_head __iomem *regs_h;
+ struct crb_regs_tail __iomem *regs_t;
u8 __iomem *cmd;
u8 __iomem *rsp;
u32 cmd_size;
@@ -104,7 +115,7 @@ 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);
+ iowrite32(CRB_CTRL_REQ_GO_IDLE, &priv->regs_t->ctrl_req);
/* we don't really care when this settles */

return 0;
@@ -128,21 +139,23 @@ static int __maybe_unused crb_cmd_ready(struct device *dev,
struct crb_priv *priv)
{
ktime_t stop, start;
+ u32 req;

if (priv->flags & CRB_FL_ACPI_START)
return 0;

- iowrite32(CRB_CTRL_REQ_CMD_READY, &priv->cca->req);
+ iowrite32(CRB_CTRL_REQ_CMD_READY, &priv->regs_t->ctrl_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))
+ req = ioread32(&priv->regs_t->ctrl_req);
+ if (!(req & CRB_CTRL_REQ_CMD_READY))
return 0;
usleep_range(50, 100);
} while (ktime_before(ktime_get(), stop));

- if (ioread32(&priv->cca->req) & CRB_CTRL_REQ_CMD_READY) {
+ if (ioread32(&priv->regs_t->ctrl_req) & CRB_CTRL_REQ_CMD_READY) {
dev_warn(dev, "cmdReady timed out\n");
return -ETIME;
}
@@ -155,7 +168,7 @@ static u8 crb_status(struct tpm_chip *chip)
struct crb_priv *priv = dev_get_drvdata(&chip->dev);
u8 sts = 0;

- if ((ioread32(&priv->cca->start) & CRB_START_INVOKE) !=
+ if ((ioread32(&priv->regs_t->ctrl_start) & CRB_START_INVOKE) !=
CRB_START_INVOKE)
sts |= CRB_DRV_STS_COMPLETE;

@@ -171,7 +184,7 @@ static int crb_recv(struct tpm_chip *chip, u8 *buf, size_t count)
if (count < 6)
return -EIO;

- if (ioread32(&priv->cca->sts) & CRB_CTRL_STS_ERROR)
+ if (ioread32(&priv->regs_t->ctrl_sts) & CRB_CTRL_STS_ERROR)
return -EIO;

memcpy_fromio(buf, priv->rsp, 6);
@@ -210,7 +223,7 @@ static int crb_send(struct tpm_chip *chip, u8 *buf, size_t len)
/* Zero the cancel register so that the next command will not get
* canceled.
*/
- iowrite32(0, &priv->cca->cancel);
+ iowrite32(0, &priv->regs_t->ctrl_cancel);

if (len > priv->cmd_size) {
dev_err(&chip->dev, "invalid command count value %zd %d\n",
@@ -224,7 +237,7 @@ static int crb_send(struct tpm_chip *chip, u8 *buf, size_t len)
wmb();

if (priv->flags & CRB_FL_CRB_START)
- iowrite32(CRB_START_INVOKE, &priv->cca->start);
+ iowrite32(CRB_START_INVOKE, &priv->regs_t->ctrl_start);

if (priv->flags & CRB_FL_ACPI_START)
rc = crb_do_acpi_start(chip);
@@ -236,7 +249,7 @@ static void crb_cancel(struct tpm_chip *chip)
{
struct crb_priv *priv = dev_get_drvdata(&chip->dev);

- iowrite32(CRB_CANCEL_INVOKE, &priv->cca->cancel);
+ iowrite32(CRB_CANCEL_INVOKE, &priv->regs_t->ctrl_cancel);

if ((priv->flags & CRB_FL_ACPI_START) && crb_do_acpi_start(chip))
dev_err(&chip->dev, "ACPI Start failed\n");
@@ -245,7 +258,7 @@ static void crb_cancel(struct tpm_chip *chip)
static bool crb_req_canceled(struct tpm_chip *chip, u8 status)
{
struct crb_priv *priv = dev_get_drvdata(&chip->dev);
- u32 cancel = ioread32(&priv->cca->cancel);
+ u32 cancel = ioread32(&priv->regs_t->ctrl_cancel);

return (cancel & CRB_CANCEL_INVOKE) == CRB_CANCEL_INVOKE;
}
@@ -322,10 +335,22 @@ static int crb_map_io(struct acpi_device *device, struct crb_priv *priv,
if (IS_ERR(priv->iobase))
return PTR_ERR(priv->iobase);

- priv->cca = crb_map_res(dev, priv, &io_res, buf->control_address,
- sizeof(struct crb_control_area));
- if (IS_ERR(priv->cca))
- return PTR_ERR(priv->cca);
+ /* The ACPI IO region starts at the head area and continues to include
+ * the control area, as one nice sane region except for some older
+ * stuff that puts the control area outside the ACPI IO region.
+ */
+ if (!(priv->flags & CRB_FL_ACPI_START)) {
+ if (buf->control_address == io_res.start +
+ sizeof(*priv->regs_h))
+ priv->regs_h = priv->iobase;
+ else
+ dev_warn(dev, FW_BUG "Bad ACPI memory layout");
+ }
+
+ priv->regs_t = crb_map_res(dev, priv, &io_res, buf->control_address,
+ sizeof(struct crb_regs_tail));
+ if (IS_ERR(priv->regs_t))
+ return PTR_ERR(priv->regs_t);

/*
* PTT HW bug w/a: wake up the device to access
@@ -335,10 +360,10 @@ static int crb_map_io(struct acpi_device *device, struct crb_priv *priv,
if (ret)
return ret;

- pa_high = ioread32(&priv->cca->cmd_pa_high);
- pa_low = ioread32(&priv->cca->cmd_pa_low);
+ pa_high = ioread32(&priv->regs_t->ctrl_cmd_pa_high);
+ pa_low = ioread32(&priv->regs_t->ctrl_cmd_pa_low);
cmd_pa = ((u64)pa_high << 32) | pa_low;
- cmd_size = ioread32(&priv->cca->cmd_size);
+ cmd_size = ioread32(&priv->regs_t->ctrl_cmd_size);

dev_dbg(dev, "cmd_hi = %X cmd_low = %X cmd_size %X\n",
pa_high, pa_low, cmd_size);
@@ -349,9 +374,9 @@ static int crb_map_io(struct acpi_device *device, struct crb_priv *priv,
goto out;
}

- memcpy_fromio(&rsp_pa, &priv->cca->rsp_pa, 8);
+ memcpy_fromio(&rsp_pa, &priv->regs_t->ctrl_rsp_pa, 8);
rsp_pa = le64_to_cpu(rsp_pa);
- rsp_size = ioread32(&priv->cca->rsp_size);
+ rsp_size = ioread32(&priv->regs_t->ctrl_rsp_size);

if (cmd_pa != rsp_pa) {
priv->rsp = crb_map_res(dev, priv, &io_res, rsp_pa, rsp_size);
--
2.9.3