[PATCH v5 09/10] bus: mhi: core: Read and save device hardware information from BHI

Bhaumik Bhatt
2020-07-23T22:37:11Z

Device hardware specific information such as serial number and the OEM
PK hash can be read using BHI and saved on host to identify the
endpoint.

Signed-off-by: Bhaumik Bhatt <bbhatt@codeaurora.org>
Reviewed-by: Jeffrey Hugo <jhugo@codeaurora.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
---
drivers/bus/mhi/core/boot.c | 17 ++++++++++++++++-
include/linux/mhi.h | 6 ++++++
2 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/drivers/bus/mhi/core/boot.c b/drivers/bus/mhi/core/boot.c
index 0b38014..24422f5 100644
--- a/drivers/bus/mhi/core/boot.c
+++ b/drivers/bus/mhi/core/boot.c
@@ -392,13 +392,28 @@ void mhi_fw_load_handler(struct mhi_controller *mhi_cntrl)
void *buf;
dma_addr_t dma_addr;
size_t size;
- int ret;
+ int i, ret;

if (MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state)) {
dev_err(dev, "Device MHI is not in valid state\n");
return;
}

+ /* save hardware info from BHI */
+ ret = mhi_read_reg(mhi_cntrl, mhi_cntrl->bhi, BHI_SERIALNU,
+ &mhi_cntrl->serial_number);
+ if (ret)
+ dev_err(dev, "Could not capture serial number via BHI\n");
+
+ for (i = 0; i < ARRAY_SIZE(mhi_cntrl->oem_pk_hash); i++) {
+ ret = mhi_read_reg(mhi_cntrl, mhi_cntrl->bhi, BHI_OEMPKHASH(i),
+ &mhi_cntrl->oem_pk_hash[i]);
+ if (ret) {
+ dev_err(dev, "Could not capture OEM PK HASH via BHI\n");
+ break;
+ }
+ }
+
/* If device is in pass through, do reset to ready state transition */
if (mhi_cntrl->ee == MHI_EE_PTHRU)
goto fw_load_ee_pthru;
diff --git a/include/linux/mhi.h b/include/linux/mhi.h
index b1e8b4f..dad6246 100644
--- a/include/linux/mhi.h
+++ b/include/linux/mhi.h
@@ -16,6 +16,8 @@
#include <linux/wait.h>
#include <linux/workqueue.h>

+#define MHI_MAX_OEM_PK_HASH_SEGMENTS 16
+
struct mhi_chan;
struct mhi_event;
struct mhi_ctxt;
@@ -315,6 +317,8 @@ struct mhi_controller_config {
* @device_number: MHI controller device number
* @major_version: MHI controller major revision number
* @minor_version: MHI controller minor revision number
+ * @serial_number: MHI controller serial number obtained from BHI
+ * @oem_pk_hash: MHI controller OEM PK Hash obtained from BHI
* @mhi_event: MHI event ring configurations table
* @mhi_cmd: MHI command ring configurations table
* @mhi_ctxt: MHI device context, shared memory between host and device
@@ -394,6 +398,8 @@ struct mhi_controller {
u32 device_number;
u32 major_version;
u32 minor_version;
+ u32 serial_number;
+ u32 oem_pk_hash[MHI_MAX_OEM_PK_HASH_SEGMENTS];

struct mhi_event *mhi_event;
struct mhi_cmd *mhi_cmd;