[tpmdd-devel,v4] tpm: Enable CLKRUN protocol for Braswell systems

Submitted by Azhar Shaikh on June 8, 2017, 11:46 p.m.

Details

Message ID 1496965593-187931-1-git-send-email-azhar.shaikh@intel.com
State New
Headers show

Commit Message

Azhar Shaikh June 8, 2017, 11:46 p.m.
To overcome a hardware limitation on Intel Braswell systems,
disable CLKRUN protocol during TPM transactions and re-enable
once the transaction is completed.

Signed-off-by: Azhar Shaikh <azhar.shaikh@intel.com>
---
Changes from v1:
- Add CONFIG_X86 around disable_lpc_clk_run () and enable_lpc_clk_run() to avoid
- build breakage on architectures which do not implement kmap_atomic_pfn()

Changes from v2:
- Use ioremap()/iounmap() instead of kmap_atomic_pfn()/kunmap_atomic()
- Move is_bsw() and all macros from tpm.h to tpm_tis.c file.
- Add the is_bsw() check in disable_lpc_clk_run() and enable_lpc_clk_run()
- instead of adding it in each read/write API.

Changes from v3:
- Move the code under #ifdef CONFIG_X86 and create stub functions for everything else
- Rename the functions disable_lpc_clk_run() -> tpm_platform_begin_xfer() and
- enable_lpc_clk_run() -> tpm_platform_end_xfer()
- Remove wmb()

 drivers/char/tpm/tpm.h     |   4 ++
 drivers/char/tpm/tpm_tis.c | 112 +++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 116 insertions(+)

Comments

Jarkko Sakkinen June 10, 2017, 11:13 a.m.
On Thu, Jun 08, 2017 at 04:46:33PM -0700, Azhar Shaikh wrote:
> To overcome a hardware limitation on Intel Braswell systems,
> disable CLKRUN protocol during TPM transactions and re-enable
> once the transaction is completed.
> 
> Signed-off-by: Azhar Shaikh <azhar.shaikh@intel.com>
> ---
> Changes from v1:
> - Add CONFIG_X86 around disable_lpc_clk_run () and enable_lpc_clk_run() to avoid
> - build breakage on architectures which do not implement kmap_atomic_pfn()
> 
> Changes from v2:
> - Use ioremap()/iounmap() instead of kmap_atomic_pfn()/kunmap_atomic()
> - Move is_bsw() and all macros from tpm.h to tpm_tis.c file.
> - Add the is_bsw() check in disable_lpc_clk_run() and enable_lpc_clk_run()
> - instead of adding it in each read/write API.
> 
> Changes from v3:
> - Move the code under #ifdef CONFIG_X86 and create stub functions for everything else
> - Rename the functions disable_lpc_clk_run() -> tpm_platform_begin_xfer() and
> - enable_lpc_clk_run() -> tpm_platform_end_xfer()
> - Remove wmb()

The wrong parameter order in outb() is not worth of mentioning in your
opinion?

Related.

I looked again the kmap version of the patch and still cannot figure
out what could be wrong. Obviously the wrong outb() cause unexpected
behavior.

Do you have chances to grab klog from kmap version with correct outb?

/Jarkko

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Azhar Shaikh June 10, 2017, 4:35 p.m.
> -----Original Message-----
> From: Jarkko Sakkinen [mailto:jarkko.sakkinen@linux.intel.com]
> Sent: Saturday, June 10, 2017 4:14 AM
> To: Shaikh, Azhar <azhar.shaikh@intel.com>
> Cc: jgunthorpe@obsidianresearch.com; tpmdd-devel@lists.sourceforge.net;
> linux-kernel@vger.kernel.org; linux-security-module@vger.kernel.org
> Subject: Re: [PATCH v4] tpm: Enable CLKRUN protocol for Braswell systems
> 
> On Thu, Jun 08, 2017 at 04:46:33PM -0700, Azhar Shaikh wrote:
> > To overcome a hardware limitation on Intel Braswell systems, disable
> > CLKRUN protocol during TPM transactions and re-enable once the
> > transaction is completed.
> >
> > Signed-off-by: Azhar Shaikh <azhar.shaikh@intel.com>
> > ---
> > Changes from v1:
> > - Add CONFIG_X86 around disable_lpc_clk_run () and
> > enable_lpc_clk_run() to avoid
> > - build breakage on architectures which do not implement
> > kmap_atomic_pfn()
> >
> > Changes from v2:
> > - Use ioremap()/iounmap() instead of
> kmap_atomic_pfn()/kunmap_atomic()
> > - Move is_bsw() and all macros from tpm.h to tpm_tis.c file.
> > - Add the is_bsw() check in disable_lpc_clk_run() and
> > enable_lpc_clk_run()
> > - instead of adding it in each read/write API.
> >
> > Changes from v3:
> > - Move the code under #ifdef CONFIG_X86 and create stub functions for
> > everything else
> > - Rename the functions disable_lpc_clk_run() ->
> > tpm_platform_begin_xfer() and
> > - enable_lpc_clk_run() -> tpm_platform_end_xfer()
> > - Remove wmb()
> 
> The wrong parameter order in outb() is not worth of mentioning in your
> opinion?
> 

Oh yes! It is definitely worth mentioning. I forgot to mention that.
Will definitely mention it in the changelog for the next version if any or will re send v4 with updated changelog for v3.

> Related.
> 
> I looked again the kmap version of the patch and still cannot figure out what
> could be wrong. Obviously the wrong outb() cause unexpected behavior.
> 
> Do you have chances to grab klog from kmap version with correct outb?
> 

I have not tried the kmap version with corrected outb(). Will give that a try.

> /Jarkko

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Jarkko Sakkinen June 12, 2017, 7:50 a.m.
On Sat, Jun 10, 2017 at 04:35:50PM +0000, Shaikh, Azhar wrote:
> 
> 
> > -----Original Message-----
> > From: Jarkko Sakkinen [mailto:jarkko.sakkinen@linux.intel.com]
> > Sent: Saturday, June 10, 2017 4:14 AM
> > To: Shaikh, Azhar <azhar.shaikh@intel.com>
> > Cc: jgunthorpe@obsidianresearch.com; tpmdd-devel@lists.sourceforge.net;
> > linux-kernel@vger.kernel.org; linux-security-module@vger.kernel.org
> > Subject: Re: [PATCH v4] tpm: Enable CLKRUN protocol for Braswell systems
> > 
> > On Thu, Jun 08, 2017 at 04:46:33PM -0700, Azhar Shaikh wrote:
> > > To overcome a hardware limitation on Intel Braswell systems, disable
> > > CLKRUN protocol during TPM transactions and re-enable once the
> > > transaction is completed.
> > >
> > > Signed-off-by: Azhar Shaikh <azhar.shaikh@intel.com>
> > > ---
> > > Changes from v1:
> > > - Add CONFIG_X86 around disable_lpc_clk_run () and
> > > enable_lpc_clk_run() to avoid
> > > - build breakage on architectures which do not implement
> > > kmap_atomic_pfn()
> > >
> > > Changes from v2:
> > > - Use ioremap()/iounmap() instead of
> > kmap_atomic_pfn()/kunmap_atomic()
> > > - Move is_bsw() and all macros from tpm.h to tpm_tis.c file.
> > > - Add the is_bsw() check in disable_lpc_clk_run() and
> > > enable_lpc_clk_run()
> > > - instead of adding it in each read/write API.
> > >
> > > Changes from v3:
> > > - Move the code under #ifdef CONFIG_X86 and create stub functions for
> > > everything else
> > > - Rename the functions disable_lpc_clk_run() ->
> > > tpm_platform_begin_xfer() and
> > > - enable_lpc_clk_run() -> tpm_platform_end_xfer()
> > > - Remove wmb()
> > 
> > The wrong parameter order in outb() is not worth of mentioning in your
> > opinion?
> > 
> 
> Oh yes! It is definitely worth mentioning. I forgot to mention that.
> Will definitely mention it in the changelog for the next version if any or will re send v4 with updated changelog for v3.
> 
> > Related.
> > 
> > I looked again the kmap version of the patch and still cannot figure out what
> > could be wrong. Obviously the wrong outb() cause unexpected behavior.
> > 
> > Do you have chances to grab klog from kmap version with correct outb?
> > 
> 
> I have not tried the kmap version with corrected outb(). Will give that a try.
> 
> > /Jarkko

Thank you!

/Jarkko

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Azhar Shaikh June 14, 2017, 12:51 a.m.
> -----Original Message-----
> From: Jarkko Sakkinen [mailto:jarkko.sakkinen@linux.intel.com]
> Sent: Monday, June 12, 2017 12:50 AM
> To: Shaikh, Azhar <azhar.shaikh@intel.com>
> Cc: jgunthorpe@obsidianresearch.com; tpmdd-devel@lists.sourceforge.net;
> linux-kernel@vger.kernel.org; linux-security-module@vger.kernel.org
> Subject: Re: [PATCH v4] tpm: Enable CLKRUN protocol for Braswell systems
> 
> On Sat, Jun 10, 2017 at 04:35:50PM +0000, Shaikh, Azhar wrote:
> >
> >
> > > -----Original Message-----
> > > From: Jarkko Sakkinen [mailto:jarkko.sakkinen@linux.intel.com]
> > > Sent: Saturday, June 10, 2017 4:14 AM
> > > To: Shaikh, Azhar <azhar.shaikh@intel.com>
> > > Cc: jgunthorpe@obsidianresearch.com;
> > > tpmdd-devel@lists.sourceforge.net;
> > > linux-kernel@vger.kernel.org; linux-security-module@vger.kernel.org
> > > Subject: Re: [PATCH v4] tpm: Enable CLKRUN protocol for Braswell
> > > systems
> > >
> > > On Thu, Jun 08, 2017 at 04:46:33PM -0700, Azhar Shaikh wrote:
> > > > To overcome a hardware limitation on Intel Braswell systems,
> > > > disable CLKRUN protocol during TPM transactions and re-enable once
> > > > the transaction is completed.
> > > >
> > > > Signed-off-by: Azhar Shaikh <azhar.shaikh@intel.com>
> > > > ---
> > > > Changes from v1:
> > > > - Add CONFIG_X86 around disable_lpc_clk_run () and
> > > > enable_lpc_clk_run() to avoid
> > > > - build breakage on architectures which do not implement
> > > > kmap_atomic_pfn()
> > > >
> > > > Changes from v2:
> > > > - Use ioremap()/iounmap() instead of
> > > kmap_atomic_pfn()/kunmap_atomic()
> > > > - Move is_bsw() and all macros from tpm.h to tpm_tis.c file.
> > > > - Add the is_bsw() check in disable_lpc_clk_run() and
> > > > enable_lpc_clk_run()
> > > > - instead of adding it in each read/write API.
> > > >
> > > > Changes from v3:
> > > > - Move the code under #ifdef CONFIG_X86 and create stub functions
> > > > for everything else
> > > > - Rename the functions disable_lpc_clk_run() ->
> > > > tpm_platform_begin_xfer() and
> > > > - enable_lpc_clk_run() -> tpm_platform_end_xfer()
> > > > - Remove wmb()
> > >
> > > The wrong parameter order in outb() is not worth of mentioning in
> > > your opinion?
> > >
> >
> > Oh yes! It is definitely worth mentioning. I forgot to mention that.
> > Will definitely mention it in the changelog for the next version if any or will
> re send v4 with updated changelog for v3.
> >
> > > Related.
> > >
> > > I looked again the kmap version of the patch and still cannot figure
> > > out what could be wrong. Obviously the wrong outb() cause unexpected
> behavior.
> > >
> > > Do you have chances to grab klog from kmap version with correct outb?
> > >
> >
> > I have not tried the kmap version with corrected outb(). Will give that a try.
> >
> > > /Jarkko
> 
> Thank you!
> 

Even with the corrected outb(), kmap version fails to boot. Could not get boot logs :-(

> /Jarkko

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Jarkko Sakkinen June 14, 2017, 2:46 p.m.
On Wed, Jun 14, 2017 at 12:51:25AM +0000, Shaikh, Azhar wrote:
> 
> 
> > -----Original Message-----
> > From: Jarkko Sakkinen [mailto:jarkko.sakkinen@linux.intel.com]
> > Sent: Monday, June 12, 2017 12:50 AM
> > To: Shaikh, Azhar <azhar.shaikh@intel.com>
> > Cc: jgunthorpe@obsidianresearch.com; tpmdd-devel@lists.sourceforge.net;
> > linux-kernel@vger.kernel.org; linux-security-module@vger.kernel.org
> > Subject: Re: [PATCH v4] tpm: Enable CLKRUN protocol for Braswell systems
> > 
> > On Sat, Jun 10, 2017 at 04:35:50PM +0000, Shaikh, Azhar wrote:
> > >
> > >
> > > > -----Original Message-----
> > > > From: Jarkko Sakkinen [mailto:jarkko.sakkinen@linux.intel.com]
> > > > Sent: Saturday, June 10, 2017 4:14 AM
> > > > To: Shaikh, Azhar <azhar.shaikh@intel.com>
> > > > Cc: jgunthorpe@obsidianresearch.com;
> > > > tpmdd-devel@lists.sourceforge.net;
> > > > linux-kernel@vger.kernel.org; linux-security-module@vger.kernel.org
> > > > Subject: Re: [PATCH v4] tpm: Enable CLKRUN protocol for Braswell
> > > > systems
> > > >
> > > > On Thu, Jun 08, 2017 at 04:46:33PM -0700, Azhar Shaikh wrote:
> > > > > To overcome a hardware limitation on Intel Braswell systems,
> > > > > disable CLKRUN protocol during TPM transactions and re-enable once
> > > > > the transaction is completed.
> > > > >
> > > > > Signed-off-by: Azhar Shaikh <azhar.shaikh@intel.com>
> > > > > ---
> > > > > Changes from v1:
> > > > > - Add CONFIG_X86 around disable_lpc_clk_run () and
> > > > > enable_lpc_clk_run() to avoid
> > > > > - build breakage on architectures which do not implement
> > > > > kmap_atomic_pfn()
> > > > >
> > > > > Changes from v2:
> > > > > - Use ioremap()/iounmap() instead of
> > > > kmap_atomic_pfn()/kunmap_atomic()
> > > > > - Move is_bsw() and all macros from tpm.h to tpm_tis.c file.
> > > > > - Add the is_bsw() check in disable_lpc_clk_run() and
> > > > > enable_lpc_clk_run()
> > > > > - instead of adding it in each read/write API.
> > > > >
> > > > > Changes from v3:
> > > > > - Move the code under #ifdef CONFIG_X86 and create stub functions
> > > > > for everything else
> > > > > - Rename the functions disable_lpc_clk_run() ->
> > > > > tpm_platform_begin_xfer() and
> > > > > - enable_lpc_clk_run() -> tpm_platform_end_xfer()
> > > > > - Remove wmb()
> > > >
> > > > The wrong parameter order in outb() is not worth of mentioning in
> > > > your opinion?
> > > >
> > >
> > > Oh yes! It is definitely worth mentioning. I forgot to mention that.
> > > Will definitely mention it in the changelog for the next version if any or will
> > re send v4 with updated changelog for v3.
> > >
> > > > Related.
> > > >
> > > > I looked again the kmap version of the patch and still cannot figure
> > > > out what could be wrong. Obviously the wrong outb() cause unexpected
> > behavior.
> > > >
> > > > Do you have chances to grab klog from kmap version with correct outb?
> > > >
> > >
> > > I have not tried the kmap version with corrected outb(). Will give that a try.
> > >
> > > > /Jarkko
> > 
> > Thank you!
> > 
> 
> Even with the corrected outb(), kmap version fails to boot. Could not get boot logs :-(
> 
> > /Jarkko

Lets go with the ioremap() version for now.

/Jarkko

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Azhar Shaikh June 14, 2017, 5:17 p.m.
> -----Original Message-----
> From: Jarkko Sakkinen [mailto:jarkko.sakkinen@linux.intel.com]
> Sent: Wednesday, June 14, 2017 7:46 AM
> To: Shaikh, Azhar <azhar.shaikh@intel.com>
> Cc: jgunthorpe@obsidianresearch.com; tpmdd-devel@lists.sourceforge.net;
> linux-kernel@vger.kernel.org; linux-security-module@vger.kernel.org
> Subject: Re: [PATCH v4] tpm: Enable CLKRUN protocol for Braswell systems
> 
> On Wed, Jun 14, 2017 at 12:51:25AM +0000, Shaikh, Azhar wrote:
> >
> >
> > > -----Original Message-----
> > > From: Jarkko Sakkinen [mailto:jarkko.sakkinen@linux.intel.com]
> > > Sent: Monday, June 12, 2017 12:50 AM
> > > To: Shaikh, Azhar <azhar.shaikh@intel.com>
> > > Cc: jgunthorpe@obsidianresearch.com;
> > > tpmdd-devel@lists.sourceforge.net;
> > > linux-kernel@vger.kernel.org; linux-security-module@vger.kernel.org
> > > Subject: Re: [PATCH v4] tpm: Enable CLKRUN protocol for Braswell
> > > systems
> > >
> > > On Sat, Jun 10, 2017 at 04:35:50PM +0000, Shaikh, Azhar wrote:
> > > >
> > > >
> > > > > -----Original Message-----
> > > > > From: Jarkko Sakkinen [mailto:jarkko.sakkinen@linux.intel.com]
> > > > > Sent: Saturday, June 10, 2017 4:14 AM
> > > > > To: Shaikh, Azhar <azhar.shaikh@intel.com>
> > > > > Cc: jgunthorpe@obsidianresearch.com;
> > > > > tpmdd-devel@lists.sourceforge.net;
> > > > > linux-kernel@vger.kernel.org;
> > > > > linux-security-module@vger.kernel.org
> > > > > Subject: Re: [PATCH v4] tpm: Enable CLKRUN protocol for Braswell
> > > > > systems
> > > > >
> > > > > On Thu, Jun 08, 2017 at 04:46:33PM -0700, Azhar Shaikh wrote:
> > > > > > To overcome a hardware limitation on Intel Braswell systems,
> > > > > > disable CLKRUN protocol during TPM transactions and re-enable
> > > > > > once the transaction is completed.
> > > > > >
> > > > > > Signed-off-by: Azhar Shaikh <azhar.shaikh@intel.com>
> > > > > > ---
> > > > > > Changes from v1:
> > > > > > - Add CONFIG_X86 around disable_lpc_clk_run () and
> > > > > > enable_lpc_clk_run() to avoid
> > > > > > - build breakage on architectures which do not implement
> > > > > > kmap_atomic_pfn()
> > > > > >
> > > > > > Changes from v2:
> > > > > > - Use ioremap()/iounmap() instead of
> > > > > kmap_atomic_pfn()/kunmap_atomic()
> > > > > > - Move is_bsw() and all macros from tpm.h to tpm_tis.c file.
> > > > > > - Add the is_bsw() check in disable_lpc_clk_run() and
> > > > > > enable_lpc_clk_run()
> > > > > > - instead of adding it in each read/write API.
> > > > > >
> > > > > > Changes from v3:
> > > > > > - Move the code under #ifdef CONFIG_X86 and create stub
> > > > > > functions for everything else
> > > > > > - Rename the functions disable_lpc_clk_run() ->
> > > > > > tpm_platform_begin_xfer() and
> > > > > > - enable_lpc_clk_run() -> tpm_platform_end_xfer()
> > > > > > - Remove wmb()
> > > > >
> > > > > The wrong parameter order in outb() is not worth of mentioning
> > > > > in your opinion?
> > > > >
> > > >
> > > > Oh yes! It is definitely worth mentioning. I forgot to mention that.
> > > > Will definitely mention it in the changelog for the next version
> > > > if any or will
> > > re send v4 with updated changelog for v3.
> > > >
> > > > > Related.
> > > > >
> > > > > I looked again the kmap version of the patch and still cannot
> > > > > figure out what could be wrong. Obviously the wrong outb() cause
> > > > > unexpected
> > > behavior.
> > > > >
> > > > > Do you have chances to grab klog from kmap version with correct
> outb?
> > > > >
> > > >
> > > > I have not tried the kmap version with corrected outb(). Will give that a
> try.
> > > >
> > > > > /Jarkko
> > >
> > > Thank you!
> > >
> >
> > Even with the corrected outb(), kmap version fails to boot. Could not
> > get boot logs :-(
> >
> > > /Jarkko
> 
> Lets go with the ioremap() version for now.
> 

Okay. I will re-send the same [PATCH v4] after updating the change log for v3.

> /Jarkko

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Patch hide | download patch | download mbox

diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
index 4b4c8dee3096..6b769fbc4407 100644
--- a/drivers/char/tpm/tpm.h
+++ b/drivers/char/tpm/tpm.h
@@ -36,6 +36,10 @@ 
 #include <linux/highmem.h>
 #include <crypto/hash_info.h>
 
+#ifdef CONFIG_X86
+#include <asm/intel-family.h>
+#endif
+
 enum tpm_const {
 	TPM_MINOR = 224,	/* officially assigned */
 	TPM_BUFSIZE = 4096,
diff --git a/drivers/char/tpm/tpm_tis.c b/drivers/char/tpm/tpm_tis.c
index c7e1384f1b08..ce6f1a8b0510 100644
--- a/drivers/char/tpm/tpm_tis.c
+++ b/drivers/char/tpm/tpm_tis.c
@@ -89,13 +89,93 @@  static inline int is_itpm(struct acpi_device *dev)
 }
 #endif
 
+#ifdef CONFIG_X86
+#define INTEL_LEGACY_BLK_BASE_ADDR      0xFED08000
+#define ILB_REMAP_SIZE			0x100
+#define LPC_CNTRL_REG_OFFSET            0x84
+#define LPC_CLKRUN_EN                   (1 << 2)
+
+void __iomem *ilb_base_addr;
+
+static inline bool is_bsw(void)
+{
+	return ((boot_cpu_data.x86_model == INTEL_FAM6_ATOM_AIRMONT) ? 1 : 0);
+}
+
+/**
+ * tpm_platform_begin_xfer() - clear LPC CLKRUN_EN i.e. clocks will be running
+ */
+static void tpm_platform_begin_xfer(void)
+{
+	u32 clkrun_val;
+
+	if (!is_bsw())
+		return;
+
+	clkrun_val = ioread32(ilb_base_addr + LPC_CNTRL_REG_OFFSET);
+
+	/* Disable LPC CLKRUN# */
+	clkrun_val &= ~LPC_CLKRUN_EN;
+	iowrite32(clkrun_val, ilb_base_addr + LPC_CNTRL_REG_OFFSET);
+
+	/*
+	 * Write any random value on port 0x80 which is on LPC, to make
+	 * sure LPC clock is running before sending any TPM command.
+	 */
+	outb(0xCC, 0x80);
+
+}
+
+/**
+ * tpm_platform_end_xfer() - set LPC CLKRUN_EN i.e. clocks can be turned off
+ */
+static void tpm_platform_end_xfer(void)
+{
+	u32 clkrun_val;
+
+	if (!is_bsw())
+		return;
+
+	clkrun_val = ioread32(ilb_base_addr + LPC_CNTRL_REG_OFFSET);
+
+	/* Enable LPC CLKRUN# */
+	clkrun_val |= LPC_CLKRUN_EN;
+	iowrite32(clkrun_val, ilb_base_addr + LPC_CNTRL_REG_OFFSET);
+
+	/*
+	 * Write any random value on port 0x80 which is on LPC, to make
+	 * sure LPC clock is running before sending any TPM command.
+	 */
+	outb(0xCC, 0x80);
+
+}
+#else
+static inline bool is_bsw(void)
+{
+	return false;
+}
+
+static void tpm_platform_begin_xfer(void)
+{
+}
+
+static void tpm_platform_end_xfer(void)
+{
+}
+#endif
+
 static int tpm_tcg_read_bytes(struct tpm_tis_data *data, u32 addr, u16 len,
 			      u8 *result)
 {
 	struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
 
+	tpm_platform_begin_xfer();
+
 	while (len--)
 		*result++ = ioread8(phy->iobase + addr);
+
+	tpm_platform_end_xfer();
+
 	return 0;
 }
 
@@ -104,8 +184,13 @@  static int tpm_tcg_write_bytes(struct tpm_tis_data *data, u32 addr, u16 len,
 {
 	struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
 
+	tpm_platform_begin_xfer();
+
 	while (len--)
 		iowrite8(*value++, phy->iobase + addr);
+
+	tpm_platform_end_xfer();
+
 	return 0;
 }
 
@@ -113,7 +198,12 @@  static int tpm_tcg_read16(struct tpm_tis_data *data, u32 addr, u16 *result)
 {
 	struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
 
+	tpm_platform_begin_xfer();
+
 	*result = ioread16(phy->iobase + addr);
+
+	tpm_platform_end_xfer();
+
 	return 0;
 }
 
@@ -121,7 +211,12 @@  static int tpm_tcg_read32(struct tpm_tis_data *data, u32 addr, u32 *result)
 {
 	struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
 
+	tpm_platform_begin_xfer();
+
 	*result = ioread32(phy->iobase + addr);
+
+	tpm_platform_end_xfer();
+
 	return 0;
 }
 
@@ -129,7 +224,12 @@  static int tpm_tcg_write32(struct tpm_tis_data *data, u32 addr, u32 value)
 {
 	struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
 
+	tpm_platform_begin_xfer();
+
 	iowrite32(value, phy->iobase + addr);
+
+	tpm_platform_end_xfer();
+
 	return 0;
 }
 
@@ -191,6 +291,12 @@  static int tpm_tis_pnp_init(struct pnp_dev *pnp_dev,
 		acpi_dev_handle = ACPI_HANDLE(&pnp_dev->dev);
 	}
 
+#ifdef CONFIG_X86
+	if (is_bsw())
+		ilb_base_addr = ioremap(INTEL_LEGACY_BLK_BASE_ADDR,
+					ILB_REMAP_SIZE);
+#endif
+
 	return tpm_tis_init(&pnp_dev->dev, &tpm_info, acpi_dev_handle);
 }
 
@@ -214,6 +320,12 @@  static void tpm_tis_pnp_remove(struct pnp_dev *dev)
 
 	tpm_chip_unregister(chip);
 	tpm_tis_remove(chip);
+
+#ifdef CONFIG_X86
+	if (is_bsw())
+		iounmap(ilb_base_addr);
+#endif
+
 }
 
 static struct pnp_driver tis_pnp_driver = {