stm32mp: Add OP-TEE support in bsec driver
When OP-TEE is used, the SMC for BSEC management are not available and
the STM32MP BSEC pseudo TA must be used (it is mandatory for STM32MP13
and it is a new feature for STM32MP15x).
The BSEC driver try to open a session to this PTA BSEC at probe
and use it for OTP read or write access to fuse or to shadow.
This patch also adapts the commands stm32key and stboard to handle
the BSEC_LOCK_PERM lock value instead of 1.
Signed-off-by: Patrick Delaunay <patrick.delaunay@foss.st.com>
Reviewed-by: Patrice Chotard <patrice.chotard@foss.st.com>
diff --git a/arch/arm/mach-stm32mp/bsec.c b/arch/arm/mach-stm32mp/bsec.c
index 51ccff9..fe79c98 100644
--- a/arch/arm/mach-stm32mp/bsec.c
+++ b/arch/arm/mach-stm32mp/bsec.c
@@ -10,9 +10,11 @@
#include <dm.h>
#include <log.h>
#include <misc.h>
+#include <tee.h>
#include <asm/io.h>
#include <asm/arch/bsec.h>
#include <asm/arch/stm32mp1_smc.h>
+#include <dm/device.h>
#include <dm/device_compat.h>
#include <linux/arm-smccc.h>
#include <linux/iopoll.h>
@@ -63,10 +65,43 @@
*/
#define BSEC_LOCK_PROGRAM 0x04
+#define PTA_BSEC_UUID { 0x94cf71ad, 0x80e6, 0x40b5, \
+ { 0xa7, 0xc6, 0x3d, 0xc5, 0x01, 0xeb, 0x28, 0x03 } }
+
+/*
+ * Read OTP memory
+ *
+ * [in] value[0].a OTP start offset in byte
+ * [in] value[0].b Access type (0:shadow, 1:fuse, 2:lock)
+ * [out] memref[1].buffer Output buffer to store read values
+ * [out] memref[1].size Size of OTP to be read
+ *
+ * Return codes:
+ * TEE_SUCCESS - Invoke command success
+ * TEE_ERROR_BAD_PARAMETERS - Incorrect input param
+ * TEE_ERROR_ACCESS_DENIED - OTP not accessible by caller
+ */
+#define PTA_BSEC_READ_MEM 0x0
+
/*
- * OTP status: bit 0 permanent lock
+ * Write OTP memory
+ *
+ * [in] value[0].a OTP start offset in byte
+ * [in] value[0].b Access type (0:shadow, 1:fuse, 2:lock)
+ * [in] memref[1].buffer Input buffer to read values
+ * [in] memref[1].size Size of OTP to be written
+ *
+ * Return codes:
+ * TEE_SUCCESS - Invoke command success
+ * TEE_ERROR_BAD_PARAMETERS - Incorrect input param
+ * TEE_ERROR_ACCESS_DENIED - OTP not accessible by caller
*/
-#define BSEC_LOCK_PERM BIT(0)
+#define PTA_BSEC_WRITE_MEM 0x1
+
+/* value of PTA_BSEC access type = value[in] b */
+#define SHADOW_ACCESS 0
+#define FUSE_ACCESS 1
+#define LOCK_ACCESS 2
/**
* bsec_lock() - manage lock for each type SR/SP/SW
@@ -359,6 +394,10 @@
u32 base;
};
+struct stm32mp_bsec_priv {
+ struct udevice *tee;
+};
+
static int stm32mp_bsec_read_otp(struct udevice *dev, u32 *val, u32 otp)
{
struct stm32mp_bsec_plat *plat;
@@ -470,14 +509,109 @@
return bsec_permanent_lock_otp(dev, plat->base, otp);
}
+static int bsec_pta_open_session(struct udevice *tee, u32 *tee_session)
+{
+ const struct tee_optee_ta_uuid uuid = PTA_BSEC_UUID;
+ struct tee_open_session_arg arg;
+ int rc;
+
+ memset(&arg, 0, sizeof(arg));
+ tee_optee_ta_uuid_to_octets(arg.uuid, &uuid);
+ arg.clnt_login = TEE_LOGIN_REE_KERNEL;
+ rc = tee_open_session(tee, &arg, 0, NULL);
+ if (rc < 0)
+ return -ENODEV;
+
+ *tee_session = arg.session;
+
+ return 0;
+}
+
+static int bsec_optee_open(struct udevice *dev)
+{
+ struct stm32mp_bsec_priv *priv = dev_get_priv(dev);
+ struct udevice *tee;
+ u32 tee_session;
+ int rc;
+
+ tee = tee_find_device(NULL, NULL, NULL, NULL);
+ if (!tee)
+ return -ENODEV;
+
+ /* try to open the STM32 BSEC TA */
+ rc = bsec_pta_open_session(tee, &tee_session);
+ if (rc)
+ return rc;
+
+ tee_close_session(tee, tee_session);
+
+ priv->tee = tee;
+
+ return 0;
+}
+
+static int bsec_optee_pta(struct udevice *dev, int cmd, int type, int offset,
+ void *buff, ulong size)
+{
+ struct stm32mp_bsec_priv *priv = dev_get_priv(dev);
+ u32 tee_session;
+ struct tee_invoke_arg arg;
+ struct tee_param param[2];
+ struct tee_shm *fw_shm;
+ int rc;
+
+ rc = bsec_pta_open_session(priv->tee, &tee_session);
+ if (rc)
+ return rc;
+
+ rc = tee_shm_register(priv->tee, buff, size, 0, &fw_shm);
+ if (rc)
+ goto close_session;
+
+ memset(&arg, 0, sizeof(arg));
+ arg.func = cmd;
+ arg.session = tee_session;
+
+ memset(param, 0, sizeof(param));
+
+ param[0].attr = TEE_PARAM_ATTR_TYPE_VALUE_INPUT;
+ param[0].u.value.a = offset;
+ param[0].u.value.b = type;
+
+ if (cmd == PTA_BSEC_WRITE_MEM)
+ param[1].attr = TEE_PARAM_ATTR_TYPE_MEMREF_INPUT;
+ else
+ param[1].attr = TEE_PARAM_ATTR_TYPE_MEMREF_OUTPUT;
+
+ param[1].u.memref.shm = fw_shm;
+ param[1].u.memref.size = size;
+
+ rc = tee_invoke_func(priv->tee, &arg, 2, param);
+ if (rc < 0 || arg.ret != 0) {
+ dev_err(priv->tee,
+ "PTA_BSEC invoke failed TEE err: %x, err:%x\n",
+ arg.ret, rc);
+ if (!rc)
+ rc = -EIO;
+ }
+
+ tee_shm_free(fw_shm);
+
+close_session:
+ tee_close_session(priv->tee, tee_session);
+
+ return rc;
+}
+
static int stm32mp_bsec_read(struct udevice *dev, int offset,
void *buf, int size)
{
+ struct stm32mp_bsec_priv *priv = dev_get_priv(dev);
int ret;
int i;
bool shadow = true, lock = false;
int nb_otp = size / sizeof(u32);
- int otp;
+ int otp, cmd;
unsigned int offs = offset;
if (offs >= STM32_BSEC_LOCK_OFFSET) {
@@ -491,6 +625,19 @@
if ((offs % 4) || (size % 4))
return -EINVAL;
+ if (IS_ENABLED(CONFIG_OPTEE) && priv->tee) {
+ cmd = FUSE_ACCESS;
+ if (shadow)
+ cmd = SHADOW_ACCESS;
+ if (lock)
+ cmd = LOCK_ACCESS;
+ ret = bsec_optee_pta(dev, PTA_BSEC_READ_MEM, cmd, offs, buf, size);
+ if (ret)
+ return ret;
+
+ return size;
+ }
+
otp = offs / sizeof(u32);
for (i = otp; i < (otp + nb_otp) && i <= BSEC_OTP_MAX_VALUE; i++) {
@@ -515,11 +662,12 @@
static int stm32mp_bsec_write(struct udevice *dev, int offset,
const void *buf, int size)
{
+ struct stm32mp_bsec_priv *priv = dev_get_priv(dev);
int ret = 0;
int i;
bool shadow = true, lock = false;
int nb_otp = size / sizeof(u32);
- int otp;
+ int otp, cmd;
unsigned int offs = offset;
if (offs >= STM32_BSEC_LOCK_OFFSET) {
@@ -533,6 +681,19 @@
if ((offs % 4) || (size % 4))
return -EINVAL;
+ if (IS_ENABLED(CONFIG_OPTEE) && priv->tee) {
+ cmd = FUSE_ACCESS;
+ if (shadow)
+ cmd = SHADOW_ACCESS;
+ if (lock)
+ cmd = LOCK_ACCESS;
+ ret = bsec_optee_pta(dev, PTA_BSEC_WRITE_MEM, cmd, offs, (void *)buf, size);
+ if (ret)
+ return ret;
+
+ return size;
+ }
+
otp = offs / sizeof(u32);
for (i = otp; i < otp + nb_otp && i <= BSEC_OTP_MAX_VALUE; i++) {
@@ -581,6 +742,9 @@
return ret;
}
+ if (IS_ENABLED(CONFIG_OPTEE))
+ bsec_optee_open(dev);
+
/*
* update unlocked shadow for OTP cleared by the rom code
* only executed in SPL, it is done in TF-A for TFABOOT
@@ -607,6 +771,7 @@
.of_match = stm32mp_bsec_ids,
.of_to_plat = stm32mp_bsec_of_to_plat,
.plat_auto = sizeof(struct stm32mp_bsec_plat),
+ .priv_auto = sizeof(struct stm32mp_bsec_priv),
.ops = &stm32mp_bsec_ops,
.probe = stm32mp_bsec_probe,
};