[PATCH] drivers: tee: i2c: support the NXP SE05x probe errata

[Jorge Ramirez-Ortiz, Foundries]

On 16/08/22, Oleksandr Suvorov wrote:
> Hi Jorge,
> 
> On Tue, Aug 16, 2022 at 2:28 PM Jorge Ramirez-Ortiz <jorge at foundries.io> wrote:
> >
> > Early instantiation of this I2C device would lock up when being
> > probed.
> >
> > Signed-off-by: Jorge Ramirez-Ortiz <jorge at foundries.io>
> 
> With a small note below,
> Acked-by: Oleksandr Suvorov <oleksandr.suvorov at foundries.io>
> 
> > ---
> >  drivers/tee/optee/Kconfig | 14 +++++++++++++
> >  drivers/tee/optee/i2c.c   | 44 +++++++++++++++++++++++++++++++++++----
> >  2 files changed, 54 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/tee/optee/Kconfig b/drivers/tee/optee/Kconfig
> > index d03028070b..05dfe2c9a8 100644
> > --- a/drivers/tee/optee/Kconfig
> > +++ b/drivers/tee/optee/Kconfig
> > @@ -37,6 +37,20 @@ config OPTEE_TA_SCP03
> >         help
> >           Enables support for controlling (enabling, provisioning) the
> >           Secure Channel Protocol 03 operation in the OP-TEE SCP03 TA.
> > +
> > +config TEE_I2C_NXP_SE05X_ERRATA
> > +       bool "Enable NXP SE05X Errata"
> > +       select TEE_I2C_NXP_SE05X_ERRATA_IN_BUS
> > +       default y
> 
> I doubt this should be enabled by default.

you are probably right (was just fixing the problem as was being reported by
some user).

will remove the active default

> 
> > +       help
> > +         This config prevents the I2C trampoline driver from probing
> > +         on every transfer.
> > +
> > +config TEE_I2C_NXP_SE05X_ERRATA_IN_BUS
> > +       int "I2C bus where to apply the NXP SE05X errata"
> > +       depends on TEE_I2C_NXP_SE05X_ERRATA
> > +       default 0
> > +
> >  endmenu
> >
> >  endif
> > diff --git a/drivers/tee/optee/i2c.c b/drivers/tee/optee/i2c.c
> > index ef4e10f991..a3ea34d4a2 100644
> > --- a/drivers/tee/optee/i2c.c
> > +++ b/drivers/tee/optee/i2c.c
> > @@ -3,13 +3,18 @@
> >   * Copyright (c) 2020 Foundries.io Ltd
> >   */
> >
> > +#define LOG_CATEGORY UCLASS_I2C
> > +
> >  #include <common.h>
> >  #include <dm.h>
> >  #include <i2c.h>
> > +#include <stdlib.h>
> >  #include <tee.h>
> >  #include "optee_msg.h"
> >  #include "optee_private.h"
> >
> > +#define NXP_SE05X_ADDR 0x48
> > +
> >  static int check_xfer_flags(struct udevice *chip, uint tee_flags)
> >  {
> >         uint flags;
> > @@ -30,6 +35,30 @@ static int check_xfer_flags(struct udevice *chip, uint tee_flags)
> >         return 0;
> >  }
> >
> > +static struct udevice *get_chip_dev(int bnum, int addr)
> > +{
> > +       struct udevice *chip;
> > +       struct udevice *bus;
> > +
> > +       if (IS_ENABLED(CONFIG_TEE_I2C_NXP_SE05X_ERRATA)) {
> > +               if (bnum == CONFIG_TEE_I2C_NXP_SE05X_ERRATA_IN_BUS &&
> > +                   addr == NXP_SE05X_ADDR) {
> > +                       if (uclass_get_device_by_seq(UCLASS_I2C, bnum, &bus))
> > +                               return NULL;
> > +
> > +                       if (i2c_get_chip(bus, addr, 0, &chip))
> > +                               return NULL;
> > +
> > +                       return chip;
> > +               }
> > +       }
> > +
> > +       if (i2c_get_chip_for_busnum(bnum, addr, 0, &chip))
> > +               return NULL;
> > +
> > +       return chip;
> > +}
> > +
> >  void optee_suppl_cmd_i2c_transfer(struct optee_msg_arg *arg)
> >  {
> >         const u8 attr[] = {
> > @@ -38,7 +67,8 @@ void optee_suppl_cmd_i2c_transfer(struct optee_msg_arg *arg)
> >                 OPTEE_MSG_ATTR_TYPE_RMEM_INOUT,
> >                 OPTEE_MSG_ATTR_TYPE_VALUE_OUTPUT,
> >         };
> > -       struct udevice *chip_dev;
> > +       struct udevice *chip_dev = NULL;
> > +
> >         struct tee_shm *shm;
> >         u8 *buf;
> >         int ret;
> > @@ -56,9 +86,9 @@ void optee_suppl_cmd_i2c_transfer(struct optee_msg_arg *arg)
> >         if (!buf)
> >                 goto bad;
> >
> > -       if (i2c_get_chip_for_busnum((int)arg->params[0].u.value.b,
> > -                                   (int)arg->params[0].u.value.c,
> > -                                   0, &chip_dev))
> > +       chip_dev = get_chip_dev((int)arg->params[0].u.value.b,
> > +                               (int)arg->params[0].u.value.c);
> > +       if (!chip_dev)
> >                 goto bad;
> >
> >         if (check_xfer_flags(chip_dev, arg->params[1].u.value.a))
> > @@ -66,10 +96,16 @@ void optee_suppl_cmd_i2c_transfer(struct optee_msg_arg *arg)
> >
> >         switch (arg->params[0].u.value.a) {
> >         case OPTEE_MSG_RPC_CMD_I2C_TRANSFER_RD:
> > +               log_debug("OPTEE_MSG_RPC_CMD_I2C_TRANSFER_RD %d\n",
> > +                         (size_t)arg->params[2].u.rmem.size);
> > +
> >                 ret = dm_i2c_read(chip_dev, 0, buf,
> >                                   (size_t)arg->params[2].u.rmem.size);
> >                 break;
> >         case OPTEE_MSG_RPC_CMD_I2C_TRANSFER_WR:
> > +               log_debug("OPTEE_MSG_RPC_CMD_I2C_TRANSFER_WR %d\n",
> > +                         (size_t)arg->params[2].u.rmem.size);
> > +
> >                 ret = dm_i2c_write(chip_dev, 0, buf,
> >                                    (size_t)arg->params[2].u.rmem.size);
> >                 break;
> > --
> > 2.34.1
> >
> 
> 
> -- 
> Best regards
> Oleksandr
> 
> Oleksandr Suvorov
> cryosay at gmail.com