CONFIG_IDF_TARGET="esp32p4"

# Flash (Waveshare ESP32-P4-ETH-POE ships with 16 MB QSPI flash)
CONFIG_ESPTOOLPY_FLASHSIZE_16MB=y
CONFIG_ESPTOOLPY_FLASHSIZE="16MB"

# Partition table
CONFIG_PARTITION_TABLE_CUSTOM=y
CONFIG_PARTITION_TABLE_CUSTOM_FILENAME="partitions.csv"

# PSRAM (required for 800x480 framebuffer + JPEG decode + local screens).
# 200 MHz speed is gated behind IDF_EXPERIMENTAL_FEATURES on ESP32-P4 —
# at the default 20 MHz the DPI bridge underruns continuously trying to
# feed the panel from PSRAM. 200 MHz gives ~10x more bandwidth and the
# DPI runs clean.
CONFIG_IDF_EXPERIMENTAL_FEATURES=y
CONFIG_SPIRAM=y
CONFIG_SPIRAM_MODE_HEX=y
CONFIG_SPIRAM_SPEED_200M=y
CONFIG_SPIRAM_USE_MALLOC=y
CONFIG_SPIRAM_MALLOC_ALWAYSINTERNAL=16384

# Ethernet (Waveshare ESP32-P4-ETH-POE: internal EMAC + external PHY)
CONFIG_ETH_ENABLED=y
CONFIG_ETH_USE_ESP32_EMAC=y
# EMAC RX DMA pool must exceed TCP_WND or a full-window burst overruns
# the RX descriptors and the silent tail-drop puts the sender into a
# ~200-400ms RTO stall (measured: WND=23040 with the default 20x512B
# = 10KB pool made recv bimodal — wire_max 75Mbps on clean frames,
# 200-450ms stalls on lossy ones, sender fps 20 -> 14). 1600B = one
# full MSS frame per buffer (also 1 descriptor/packet instead of 3);
# 24 x 1600 = 38.4KB >= 23040 + slack. ~44KB extra internal RAM.
CONFIG_ETH_DMA_BUFFER_SIZE=1600
CONFIG_ETH_DMA_RX_BUFFER_NUM=24

# LWIP / mDNS
CONFIG_LWIP_IPV4=y
CONFIG_LWIP_IPV6=y
CONFIG_MDNS_MAX_INTERFACES=1

# TCP receive window. History: at the IDF default (4 × MSS = 5760)
# with the OLD single recv→decode→paint task, raising WND to 65535
# regressed g2g to 17s unbounded (kernel queue buildup, no skip-
# oldest possible). The recv/decode task split + 1-deep latest-frame
# slot removed that failure mode; the instrumented baseline at 5760
# then showed the window as the dominant throttle: wire=53Mbps
# (= WND/RTT ceiling) vs ~94Mbps line rate, recv_chunk_max pinned at
# exactly 5760, sender backpressured on 44-61% of frames. 23040 =
# 16 × MSS. RECVMBOX must scale with the window (16 segments can be
# in flight; a 6-deep mbox would silently become the new cap).
# Regression tripwires when touching these: /state stream.pend_age_*
# and recv_dropped_oldest must stay flat, sender g2g must not grow.
CONFIG_LWIP_TCP_WND_DEFAULT=23040
CONFIG_LWIP_TCP_SND_BUF_DEFAULT=5760
CONFIG_LWIP_TCP_RECVMBOX_SIZE=32
CONFIG_LWIP_TCP_SACK_OUT=y

# HTTP server
CONFIG_HTTPD_MAX_REQ_HDR_LEN=1024
CONFIG_HTTPD_MAX_URI_LEN=512

# Main task stack — JPEG decode is hungry
CONFIG_ESP_MAIN_TASK_STACK_SIZE=8192

# Log level
CONFIG_LOG_DEFAULT_LEVEL_INFO=y

# OTA: dual-partition layout in partitions.csv. Rollback marks new
# images as PENDING_VERIFY at first boot; ota_arm_healthy_timer flips
# them to VALID after 30 s of healthy uptime, otherwise the bootloader
# reverts to the previous slot on the next reset.
CONFIG_BOOTLOADER_APP_ROLLBACK_ENABLE=y