From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jens Wiklander Date: Wed, 23 Dec 2020 09:12:38 +0100 Subject: [PATCH] drivers: tee: i2c trampoline driver In-Reply-To: <20201221181540.17949-1-jorge@foundries.io> References: <20201221181540.17949-1-jorge@foundries.io> Message-ID: <20201223081238.GA545999@jade> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hi Jorge, On Mon, Dec 21, 2020 at 07:15:40PM +0100, Jorge Ramirez-Ortiz wrote: > This commit gives the secure world access to the I2C bus so it can > communicate with I2C slaves (tipically those would be secure elements > like the NXP SE050). > > Tested on imx8mmevk. > > Signed-off-by: Jorge Ramirez-Ortiz > --- > drivers/tee/optee/Makefile | 1 + > drivers/tee/optee/i2c.c | 88 ++++++++++++++++++++++++ > drivers/tee/optee/optee_msg.h | 22 ++++++ > drivers/tee/optee/optee_msg_supplicant.h | 5 ++ > drivers/tee/optee/optee_private.h | 12 ++++ > drivers/tee/optee/supplicant.c | 3 + > 6 files changed, 131 insertions(+) > create mode 100644 drivers/tee/optee/i2c.c > > diff --git a/drivers/tee/optee/Makefile b/drivers/tee/optee/Makefile > index 928d3f8002..068c6e7aa1 100644 > --- a/drivers/tee/optee/Makefile > +++ b/drivers/tee/optee/Makefile > @@ -2,4 +2,5 @@ > > obj-y += core.o > obj-y += supplicant.o > +obj-$(CONFIG_DM_I2C) += i2c.o > obj-$(CONFIG_SUPPORT_EMMC_RPMB) += rpmb.o > diff --git a/drivers/tee/optee/i2c.c b/drivers/tee/optee/i2c.c > new file mode 100644 > index 0000000000..2ebbf1ff7c > --- /dev/null > +++ b/drivers/tee/optee/i2c.c > @@ -0,0 +1,88 @@ > +// SPDX-License-Identifier: BSD-2-Clause > +/* > + * Copyright (c) 2020 Foundries.io Ltd > + */ > + > +#include > +#include > +#include > +#include > +#include "optee_msg.h" > +#include "optee_private.h" > + > +static struct { > + struct udevice *dev; > + int chip; > + int bus; > +} xfer; > + > +void optee_suppl_cmd_i2c_transfer(struct udevice *dev, > + struct optee_msg_arg *arg) > +{ > + const uint64_t attr[] = { A u8 instead of uint64_t would give the same result. > + OPTEE_MSG_ATTR_TYPE_VALUE_INPUT, > + OPTEE_MSG_ATTR_TYPE_VALUE_INPUT, > + OPTEE_MSG_ATTR_TYPE_RMEM_INOUT, > + OPTEE_MSG_ATTR_TYPE_VALUE_OUTPUT, > + }; > + struct udevice *chip_dev = NULL; > + struct tee_shm *shm = NULL; > + uint8_t *buf = NULL; > + size_t len = 0; > + int chip = -1; > + int bus = -1; > + int ret = -1; > + > + if (arg->num_params != ARRAY_SIZE(attr) || > + arg->params[0].attr != attr[0] || > + arg->params[1].attr != attr[1] || > + arg->params[2].attr != attr[2] || > + arg->params[3].attr != attr[3]) { > + arg->ret = TEE_ERROR_BAD_PARAMETERS; > + return; > + } > + > + len = arg->params[2].u.tmem.size; > + shm = (struct tee_shm *)(unsigned long)arg->params[2].u.tmem.shm_ref; Please replace tmem with rmem. The OPTEE_MSG_ATTR_TYPE_RMEM_INOUT above indicates that we're dealing with a struct optee_msg_param_rmem. > + buf = shm->addr; > + if (!buf || !len) > + goto bad; > + > + bus = (int)arg->params[0].u.value.b; > + chip = (int)arg->params[0].u.value.c; > + > + if (!xfer.dev || xfer.chip != chip || xfer.bus != bus) { > + if (i2c_get_chip_for_busnum(bus, chip, 0, &chip_dev)) > + goto bad; > + > + xfer.dev = chip_dev; > + xfer.chip = chip; > + xfer.bus = bus; Is this caching safe? No risk of using stale data? Thanks, Jens > + } > + > + if (arg->params[1].u.value.a & OPTEE_MSG_RPC_CMD_I2C_FLAGS_TEN_BIT) > + if (i2c_set_chip_flags(xfer.dev, DM_I2C_CHIP_10BIT)) > + goto bad; > + > + switch (arg->params[0].u.value.a) { > + case OPTEE_MSG_RPC_CMD_I2C_TRANSFER_RD: > + ret = dm_i2c_read(xfer.dev, 0, buf, len); > + break; > + case OPTEE_MSG_RPC_CMD_I2C_TRANSFER_WR: > + ret = dm_i2c_write(xfer.dev, 0, buf, len); > + break; > + default: > + goto bad; > + } > + > + if (ret) { > + arg->ret = TEE_ERROR_COMMUNICATION; > + } else { > + arg->params[3].u.value.a = len; > + arg->ret = TEE_SUCCESS; > + } > + > + return; > +bad: > + arg->ret = TEE_ERROR_BAD_PARAMETERS; > +} > diff --git a/drivers/tee/optee/optee_msg.h b/drivers/tee/optee/optee_msg.h > index 24c60960fc..7cedb59a82 100644 > --- a/drivers/tee/optee/optee_msg.h > +++ b/drivers/tee/optee/optee_msg.h > @@ -422,4 +422,26 @@ struct optee_msg_arg { > */ > #define OPTEE_MSG_RPC_CMD_SHM_FREE 7 > > +/* > + * Access a device on an i2c bus > + * > + * [in] param[0].u.value.a mode: RD(0), WR(1) > + * [in] param[0].u.value.b i2c adapter > + * [in] param[0].u.value.c i2c chip > + * > + * [in] param[1].u.value.a i2c control flags > + * [in] param[1].u.value.b i2c retry (optional) > + * > + * [in/out] memref[2] buffer to exchange the transfer data > + * with the secure world > + * > + * [out] param[3].u.value.a bytes transferred by the driver > + */ > +#define OPTEE_MSG_RPC_CMD_I2C_TRANSFER 21 > +/* I2C master transfer modes */ > +#define OPTEE_MSG_RPC_CMD_I2C_TRANSFER_RD 0 > +#define OPTEE_MSG_RPC_CMD_I2C_TRANSFER_WR 1 > +/* I2C master control flags */ > +#define OPTEE_MSG_RPC_CMD_I2C_FLAGS_TEN_BIT BIT(0) > + > #endif /* _OPTEE_MSG_H */ > diff --git a/drivers/tee/optee/optee_msg_supplicant.h b/drivers/tee/optee/optee_msg_supplicant.h > index a0fb8063c8..963cfd4782 100644 > --- a/drivers/tee/optee/optee_msg_supplicant.h > +++ b/drivers/tee/optee/optee_msg_supplicant.h > @@ -147,6 +147,11 @@ > #define OPTEE_MSG_RPC_CMD_SHM_ALLOC 6 > #define OPTEE_MSG_RPC_CMD_SHM_FREE 7 > > +/* > + * I2C bus access > + */ > +#define OPTEE_MSG_RPC_CMD_I2C_TRANSFER 21 > + > /* > * Was OPTEE_MSG_RPC_CMD_SQL_FS, which isn't supported any longer > */ > diff --git a/drivers/tee/optee/optee_private.h b/drivers/tee/optee/optee_private.h > index 9442d1c176..d7ab1f593f 100644 > --- a/drivers/tee/optee/optee_private.h > +++ b/drivers/tee/optee/optee_private.h > @@ -60,6 +60,18 @@ static inline void optee_suppl_rpmb_release(struct udevice *dev) > } > #endif > > +#ifdef CONFIG_DM_I2C > +void optee_suppl_cmd_i2c_transfer(struct udevice *dev, > + struct optee_msg_arg *arg); > +#else > +void optee_suppl_cmd_i2c_transfer(struct udevice *dev, > + struct optee_msg_arg *arg) > +{ > + debug("OPTEE_MSG_RPC_CMD_I2C_TRANSFER not implemented\n"); > + arg->ret = TEE_ERROR_NOT_IMPLEMENTED; > +} > +#endif > + > void *optee_alloc_and_init_page_list(void *buf, ulong len, u64 *phys_buf_ptr); > > #endif /* __OPTEE_PRIVATE_H */ > diff --git a/drivers/tee/optee/supplicant.c b/drivers/tee/optee/supplicant.c > index ae042b9a20..f7738983cd 100644 > --- a/drivers/tee/optee/supplicant.c > +++ b/drivers/tee/optee/supplicant.c > @@ -89,6 +89,9 @@ void optee_suppl_cmd(struct udevice *dev, struct tee_shm *shm_arg, > case OPTEE_MSG_RPC_CMD_RPMB: > optee_suppl_cmd_rpmb(dev, arg); > break; > + case OPTEE_MSG_RPC_CMD_I2C_TRANSFER: > + optee_suppl_cmd_i2c_transfer(dev, arg); > + break; > default: > arg->ret = TEE_ERROR_NOT_IMPLEMENTED; > } > -- > 2.17.1 >