thunderbolt: Perform USB4 router NVM upgrade in two phases

The currect code expects that the router returns back the status of the
NVM authentication immediately. When tested against a real USB4 device
what happens is that the router is reset and only after that the result
is updated in the ROUTER_CS_26 register status field. This also seems to
align better what the spec suggests.

For this reason do the same what we already do with the Thunderbolt 3
devices and perform the NVM upgrade in two phases. First start the
NVM_AUTH router operation and once the router is added back after the
reset read the status in ROUTER_CS_26 and expose it to the userspace
accordingly.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

diff --git a/drivers/thunderbolt/switch.c b/drivers/thunderbolt/switch.c
index cdfd8cccfe19aa30eff1ed1e13a7b39056e18cac..a8572f49d3adc42e65998f3cd38e60443ef7ca87 100644 (file)
--- a/drivers/thunderbolt/switch.c
+++ b/drivers/thunderbolt/switch.c
@@ -2160,6 +2160,7 @@ static int tb_switch_add_dma_port(struct tb_switch *sw)
 
                fallthrough;
        case 3:
+       case 4:
                ret = tb_switch_set_uuid(sw);
                if (ret)
                        return ret;
@@ -2175,6 +2176,22 @@ static int tb_switch_add_dma_port(struct tb_switch *sw)
                break;
        }
 
+       if (sw->no_nvm_upgrade)
+               return 0;
+
+       if (tb_switch_is_usb4(sw)) {
+               ret = usb4_switch_nvm_authenticate_status(sw, &status);
+               if (ret)
+                       return ret;
+
+               if (status) {
+                       tb_sw_info(sw, "switch flash authentication failed\n");
+                       nvm_set_auth_status(sw, status);
+               }
+
+               return 0;
+       }
+
        /* Root switch DMA port requires running firmware */
        if (!tb_route(sw) && !tb_switch_is_icm(sw))
                return 0;
@@ -2183,9 +2200,6 @@ static int tb_switch_add_dma_port(struct tb_switch *sw)
        if (!sw->dma_port)
                return 0;
 
-       if (sw->no_nvm_upgrade)
-               return 0;
-
        /*
         * If there is status already set then authentication failed
         * when the dma_port_flash_update_auth() returned. Power cycling

diff --git a/drivers/thunderbolt/tb.h b/drivers/thunderbolt/tb.h
index a21000649009f5dc692d16b54451a34671d3c838..3885f2515aaeae2e1f4b3ec53daa98df45e9b2b4 100644 (file)
--- a/drivers/thunderbolt/tb.h
+++ b/drivers/thunderbolt/tb.h
@@ -972,6 +972,7 @@ int usb4_switch_nvm_read(struct tb_switch *sw, unsigned int address, void *buf,
 int usb4_switch_nvm_write(struct tb_switch *sw, unsigned int address,
                          const void *buf, size_t size);
 int usb4_switch_nvm_authenticate(struct tb_switch *sw);
+int usb4_switch_nvm_authenticate_status(struct tb_switch *sw, u32 *status);
 bool usb4_switch_query_dp_resource(struct tb_switch *sw, struct tb_port *in);
 int usb4_switch_alloc_dp_resource(struct tb_switch *sw, struct tb_port *in);
 int usb4_switch_dealloc_dp_resource(struct tb_switch *sw, struct tb_port *in);

diff --git a/drivers/thunderbolt/tb_regs.h b/drivers/thunderbolt/tb_regs.h
index e7d9529822fab3f920a0c444687b3b899c0d8ca3..67cb173a2f8ee2aaf6eef731363feba3159f4182 100644 (file)
--- a/drivers/thunderbolt/tb_regs.h
+++ b/drivers/thunderbolt/tb_regs.h
@@ -211,6 +211,7 @@ struct tb_regs_switch_header {
 #define ROUTER_CS_9                            0x09
 #define ROUTER_CS_25                           0x19
 #define ROUTER_CS_26                           0x1a
+#define ROUTER_CS_26_OPCODE_MASK               GENMASK(15, 0)
 #define ROUTER_CS_26_STATUS_MASK               GENMASK(29, 24)
 #define ROUTER_CS_26_STATUS_SHIFT              24
 #define ROUTER_CS_26_ONS                       BIT(30)

diff --git a/drivers/thunderbolt/usb4.c b/drivers/thunderbolt/usb4.c
index 40f13579a3fe7648b5033e4559deeccd068cf9cc..d88e28eee9750aa27d3657bbdd9201196d3e7ce8 100644 (file)
--- a/drivers/thunderbolt/usb4.c
+++ b/drivers/thunderbolt/usb4.c
@@ -192,7 +192,9 @@ static int usb4_switch_op(struct tb_switch *sw, u16 opcode, u8 *status)
        if (val & ROUTER_CS_26_ONS)
                return -EOPNOTSUPP;
 
-       *status = (val & ROUTER_CS_26_STATUS_MASK) >> ROUTER_CS_26_STATUS_SHIFT;
+       if (status)
+               *status = (val & ROUTER_CS_26_STATUS_MASK) >>
+                       ROUTER_CS_26_STATUS_SHIFT;
        return 0;
 }
 
@@ -634,32 +636,71 @@ int usb4_switch_nvm_write(struct tb_switch *sw, unsigned int address,
  * @sw: USB4 router
  *
  * After the new NVM has been written via usb4_switch_nvm_write(), this
- * function triggers NVM authentication process. If the authentication
- * is successful the router is power cycled and the new NVM starts
+ * function triggers NVM authentication process. The router gets power
+ * cycled and if the authentication is successful the new NVM starts
  * running. In case of failure returns negative errno.
+ *
+ * The caller should call usb4_switch_nvm_authenticate_status() to read
+ * the status of the authentication after power cycle. It should be the
+ * first router operation to avoid the status being lost.
  */
 int usb4_switch_nvm_authenticate(struct tb_switch *sw)
 {
-       u8 status = 0;
        int ret;
 
-       ret = usb4_switch_op(sw, USB4_SWITCH_OP_NVM_AUTH, &status);
+       ret = usb4_switch_op(sw, USB4_SWITCH_OP_NVM_AUTH, NULL);
+       switch (ret) {
+       /*
+        * The router is power cycled once NVM_AUTH is started so it is
+        * expected to get any of the following errors back.
+        */
+       case -EACCES:
+       case -ENOTCONN:
+       case -ETIMEDOUT:
+               return 0;
+
+       default:
+               return ret;
+       }
+}
+
+/**
+ * usb4_switch_nvm_authenticate_status() - Read status of last NVM authenticate
+ * @sw: USB4 router
+ * @status: Status code of the operation
+ *
+ * The function checks if there is status available from the last NVM
+ * authenticate router operation. If there is status then %0 is returned
+ * and the status code is placed in @status. Returns negative errno in case
+ * of failure.
+ *
+ * Must be called before any other router operation.
+ */
+int usb4_switch_nvm_authenticate_status(struct tb_switch *sw, u32 *status)
+{
+       u16 opcode;
+       u32 val;
+       int ret;
+
+       ret = tb_sw_read(sw, &val, TB_CFG_SWITCH, ROUTER_CS_26, 1);
        if (ret)
                return ret;
 
-       switch (status) {
-       case 0x0:
-               tb_sw_dbg(sw, "NVM authentication successful\n");
-               return 0;
-       case 0x1:
-               return -EINVAL;
-       case 0x2:
-               return -EAGAIN;
-       case 0x3:
-               return -EOPNOTSUPP;
-       default:
-               return -EIO;
+       /* Check that the opcode is correct */
+       opcode = val & ROUTER_CS_26_OPCODE_MASK;
+       if (opcode == USB4_SWITCH_OP_NVM_AUTH) {
+               if (val & ROUTER_CS_26_OV)
+                       return -EBUSY;
+               if (val & ROUTER_CS_26_ONS)
+                       return -EOPNOTSUPP;
+
+               *status = (val & ROUTER_CS_26_STATUS_MASK) >>
+                       ROUTER_CS_26_STATUS_SHIFT;
+       } else {
+               *status = 0;
        }
+
+       return 0;
 }
 
 /**