bus: mhi: core: Ensure non-zero session or sequence ID values are used

While writing any sequence or session identifiers, it is possible that
the host could write a zero value, whereas only non-zero values should
be supported writes to those registers. Ensure that the host does not
write a non-zero value for them and also log them in debug messages. A
macro is introduced to simplify this check and the existing checks are
also converted to use this macro.

Signed-off-by: Bhaumik Bhatt <bbhatt@codeaurora.org>
Reviewed-by: Jeffrey Hugo <jhugo@codeaurora.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20200521170249.21795-9-manivannan.sadhasivam@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Bhaumik Bhatt 2020-05-21 22:32:43 +05:30 committed by Greg Kroah-Hartman
parent 0a895f091e
commit 0ab9fcd0e7
2 changed files with 8 additions and 8 deletions

View File

@ -43,10 +43,7 @@ void mhi_rddm_prepare(struct mhi_controller *mhi_cntrl,
lower_32_bits(mhi_buf->dma_addr));
mhi_write_reg(mhi_cntrl, base, BHIE_RXVECSIZE_OFFS, mhi_buf->len);
sequence_id = prandom_u32() & BHIE_RXVECSTATUS_SEQNUM_BMSK;
if (unlikely(!sequence_id))
sequence_id = 1;
sequence_id = MHI_RANDOM_U32_NONZERO(BHIE_RXVECSTATUS_SEQNUM_BMSK);
mhi_write_reg_field(mhi_cntrl, base, BHIE_RXVECDB_OFFS,
BHIE_RXVECDB_SEQNUM_BMSK, BHIE_RXVECDB_SEQNUM_SHFT,
@ -189,7 +186,9 @@ static int mhi_fw_load_amss(struct mhi_controller *mhi_cntrl,
return -EIO;
}
dev_dbg(dev, "Starting AMSS download via BHIe\n");
sequence_id = MHI_RANDOM_U32_NONZERO(BHIE_TXVECSTATUS_SEQNUM_BMSK);
dev_dbg(dev, "Starting AMSS download via BHIe. Sequence ID:%u\n",
sequence_id);
mhi_write_reg(mhi_cntrl, base, BHIE_TXVECADDR_HIGH_OFFS,
upper_32_bits(mhi_buf->dma_addr));
@ -198,7 +197,6 @@ static int mhi_fw_load_amss(struct mhi_controller *mhi_cntrl,
mhi_write_reg(mhi_cntrl, base, BHIE_TXVECSIZE_OFFS, mhi_buf->len);
sequence_id = prandom_u32() & BHIE_TXVECSTATUS_SEQNUM_BMSK;
mhi_write_reg_field(mhi_cntrl, base, BHIE_TXVECDB_OFFS,
BHIE_TXVECDB_SEQNUM_BMSK, BHIE_TXVECDB_SEQNUM_SHFT,
sequence_id);
@ -246,14 +244,15 @@ static int mhi_fw_load_sbl(struct mhi_controller *mhi_cntrl,
goto invalid_pm_state;
}
dev_dbg(dev, "Starting SBL download via BHI\n");
session_id = MHI_RANDOM_U32_NONZERO(BHI_TXDB_SEQNUM_BMSK);
dev_dbg(dev, "Starting SBL download via BHI. Session ID:%u\n",
session_id);
mhi_write_reg(mhi_cntrl, base, BHI_STATUS, 0);
mhi_write_reg(mhi_cntrl, base, BHI_IMGADDR_HIGH,
upper_32_bits(dma_addr));
mhi_write_reg(mhi_cntrl, base, BHI_IMGADDR_LOW,
lower_32_bits(dma_addr));
mhi_write_reg(mhi_cntrl, base, BHI_IMGSIZE, size);
session_id = prandom_u32() & BHI_TXDB_SEQNUM_BMSK;
mhi_write_reg(mhi_cntrl, base, BHI_IMGTXDB, session_id);
read_unlock_bh(pm_lock);

View File

@ -452,6 +452,7 @@ enum mhi_pm_state {
#define PRIMARY_CMD_RING 0
#define MHI_DEV_WAKE_DB 127
#define MHI_MAX_MTU 0xffff
#define MHI_RANDOM_U32_NONZERO(bmsk) (prandom_u32_max(bmsk) + 1)
enum mhi_er_type {
MHI_ER_TYPE_INVALID = 0x0,