diff --git a/firmware/ice40-riscv/icE1usb/e1.c b/firmware/ice40-riscv/icE1usb/e1.c
index 59be063..6a4c73c 100644
--- a/firmware/ice40-riscv/icE1usb/e1.c
+++ b/firmware/ice40-riscv/icE1usb/e1.c
@@ -18,9 +18,16 @@
 #include "led.h" // FIXME
 
 
+// HW access
+// ---------
+
 static volatile struct e1_core * const e1_regs = (void *)(E1_CORE_BASE);
 static volatile uint8_t * const e1_data = (void *)(E1_DATA_BASE);
 
+
+// Helpers
+// -------
+
 static unsigned int
 e1_data_ofs(int mf, int frame, int ts)
 {
@@ -33,6 +40,7 @@
 	return &e1_data[e1_data_ofs(mf, frame, ts)];
 }
 
+
 // FIFOs
 // -----
 /* Note: FIFO works at 'frame' level (i.e. 32 bytes) */
@@ -98,7 +106,6 @@
 	return (ofs >> 4);
 }
 
-
 	/* Debug */
 static void
 e1f_debug(struct e1_fifo *fifo, const char *name)
@@ -207,7 +214,6 @@
 }
 
 
-
 // Main logic
 // ----------
 
@@ -232,12 +238,11 @@
 		int in_flight;
 		enum e1_pipe_state state;
 	} tx;
+
 	struct e1_error_count errors;
 } g_e1;
 
 
-
-
 void
 e1_init(uint16_t rx_cr, uint16_t tx_cr)
 {
@@ -285,8 +290,6 @@
 	e1_regs->rx.csr = g_e1.rx.cr;
 }
 
-#include "dma.h"
-
 unsigned int
 e1_rx_need_data(unsigned int usb_addr, unsigned int max_frames, unsigned int *pos)
 {