Faster BIOS flashing

Summary:
With this change we are making use of the strong (SHA256) BIOS checksum
calculation introduced in BIC fw 31.04: blocks won't be flashed if the
checksum matches. Upwards of 50% of blocks remain the same between BIOS
version, so this speeds up flashing quite a bit.

We also use larger USB blocks (also introduced in 31.04).

Graceful fallback to non-deduping is provided so this still works
with older BIC version:
if strong checksums are available, then it will perform deduplication by default (can still turn off with DEDUP=0 env variable).
if strong checksums are not available, it will fall back to weak and turn off dedup (can force it with DEDUP=2 if you want to take the risk).

Also provided is ability to turn off verification (with VERIFY=0) - will save a few seconds of flashing, can be useful to speed up dev cycle.

Test Plan:
Baseline: 12m17.122s (P151555168)
With dedup: 3m 38.52s (P151558354)
Without dedup (fallback for older BIC versions): 11m 55.38s (P151557710)

Reviewed By: benwei13

fbshipit-source-id: e68605a95e

meta-facebook/meta-fby3/recipes-fby3/fw-util/files/bic_bios.cpp

@@ -51,11 +51,13 @@ int BiosComponent::update_internal(const std::string &image, bool force) {
   me_recovery(slot_id, RECOVERY_MODE);
   cerr << "Enabling USB..." << endl;
   bic_set_gpio(slot_id, RST_USB_HUB_N, GPIO_HIGH);
-  sleep(3);
+  sleep(1);
   cerr << "Switching BIOS SPI MUX for update..." << endl;
   bic_switch_mux_for_bios_spi(slot_id, MUX_SWITCH_CPLD);
   sleep(1);
   ret = bic_update_fw(slot_id, fw_comp, (char *)image.c_str(), FORCE_UPDATE_UNSET);
+  cerr << "Disabling USB..." << endl;
+  bic_set_gpio(slot_id, RST_USB_HUB_N, GPIO_LOW);
   if (ret != 0) {
     return -1;
   }
@@ -64,8 +66,6 @@ int BiosComponent::update_internal(const std::string &image, bool force) {
   pal_set_server_power(slot_id, SERVER_12V_CYCLE);
   sleep(5);
   pal_set_server_power(slot_id, SERVER_POWER_ON);
-  cerr << "Disabling USB..." << endl;
-  bic_set_gpio(slot_id, RST_USB_HUB_N, GPIO_LOW);
   return ret;
 }
 

meta-facebook/meta-fby3/recipes-fby3/plat-libs/files/bic/bic_bios_fwupdate.c

@@ -183,6 +183,42 @@ bic_get_fw_cksum(uint8_t slot_id, uint8_t target, uint32_t offset, uint32_t len,
   return ret;
 }
 
+struct bic_get_fw_cksum_sha256_req {
+  uint8_t iana_id[3];
+  uint8_t target;
+  uint32_t offset;
+  uint32_t length;
+} __attribute__((packed));
+
+struct bic_get_fw_cksum_sha256_res {
+  uint8_t iana_id[3];
+  uint8_t cksum[32];
+} __attribute__((packed));
+
+int
+bic_get_fw_cksum_sha256(uint8_t slot_id, uint8_t target, uint32_t offset, uint32_t len, uint8_t *cksum) {
+  int ret;
+  struct bic_get_fw_cksum_sha256_req req = {
+    .iana_id = {0x9c, 0x9c, 0x00},
+    .target = target,
+    .offset = offset,
+    .length = len,
+  };
+  struct bic_get_fw_cksum_sha256_res res = {0};
+  uint8_t rlen = sizeof(res);
+
+  ret = bic_ipmb_wrapper(slot_id, NETFN_OEM_1S_REQ, BIC_CMD_OEM_FW_CKSUM_SHA256, (uint8_t *) &req, sizeof(req), (uint8_t *) &res, &rlen);
+  if (ret != 0) {
+    return -1;
+  }
+  if (rlen != sizeof(res)) {
+    return -2;
+  }
+
+  memcpy(cksum, res.cksum, sizeof(res.cksum));
+
+  return 0;
+}
 
 static int
 verify_bios_image(uint8_t slot_id, int fd, long size) {

meta-facebook/meta-fby3/recipes-fby3/plat-libs/files/bic/bic_bios_fwupdate.h

@@ -34,7 +34,8 @@ extern "C" {
 
 int print_configuration(struct libusb_device_handle *hDevice,struct libusb_config_descriptor *config);
 int active_config(struct libusb_device *dev,struct libusb_device_handle *handle);
-int bic_get_fw_cksum(uint8_t slot_id, uint8_t target, uint32_t offset, uint32_t len, uint8_t *ver);
+int bic_get_fw_cksum(uint8_t slot_id, uint8_t target, uint32_t offset, uint32_t len, uint8_t *cksum);
+int bic_get_fw_cksum_sha256(uint8_t slot_id, uint8_t target, uint32_t offset, uint32_t len, uint8_t *cksum);
 int update_bic_bios(uint8_t slot_id, uint8_t comp, char *image, uint8_t force);
 int update_bic_usb_bios(uint8_t slot_id, uint8_t comp, char *image);