Firmware: Add an additional layer of DMA-assisted sample buffering

firmware/common/LPC4320_M4_memory.ld

@@ -26,7 +26,8 @@ MEMORY
 {
 	/* rom is really the shadow region that points to SPI flash or elsewhere */
 	rom (rx)  : ORIGIN = 0x00000000, LENGTH =  1M
-	ram_local1 (rwx) : ORIGIN = 0x10000000, LENGTH =  96K
+	ram_local1 (rwx) : ORIGIN = 0x10000000, LENGTH =  64K
+	ram_usb (rw) : ORIGIN = 0x10010000, LENGTH = 32K
 	ram_local2 (rwx) : ORIGIN = 0x10080000, LENGTH =  32K
 	ram_sleep (rwx) : ORIGIN = 0x10088000, LENGTH = 8K
 }

firmware/common/LPC4330_M4_memory.ld

@@ -26,7 +26,8 @@ MEMORY
 {
 	/* rom is really the shadow region that points to SPI flash or elsewhere */
 	rom (rx)  : ORIGIN = 0x00000000, LENGTH =  128K
-	ram_local1 (rwx) : ORIGIN = 0x10000000, LENGTH =  128K
+	ram_local1 (rwx) : ORIGIN = 0x10000000, LENGTH =  96K
+	ram_usb(rw) : ORIGIN = 0x10018000, LENGTH = 32K
 	ram_local2 (rwx) : ORIGIN = 0x10080000, LENGTH =  64K
 	ram_sleep (rwx) : ORIGIN = 0x10090000, LENGTH = 8K
 }

firmware/common/LPC43xx_M4_memory.ld

@@ -35,11 +35,12 @@ MEMORY
 	 * to get performance benefit of having two USB buffers addressable
 	 * simultaneously (on two different buses of the AHB multilayer matrix)
 	 */
-	ram_usb (rwx)     : ORIGIN = 0x20008000, LENGTH = 32K
+	ram_samp (rwx)     : ORIGIN = 0x20008000, LENGTH = 32K
 }
 
-usb_bulk_buffer = ORIGIN(ram_usb);
 lz4_in_buf = ORIGIN(ram_lz4_in);
 lz4_out_buf = ORIGIN(ram_lz4_out);
+usb_samp_buffer = ORIGIN(ram_samp);
+usb_bulk_buffer = ORIGIN(ram_usb);
 m0_state = ORIGIN(ram_shared);
 PROVIDE(__ram_m0_start__ = ORIGIN(ram_m0));

firmware/common/fpga_selftest.c

@@ -37,8 +37,8 @@
 #include "streaming.h"
 
 // USB buffer used during selftests.
-#define USB_BULK_BUFFER_SIZE 0x8000
-extern uint8_t usb_bulk_buffer[USB_BULK_BUFFER_SIZE];
+#define USB_SAMP_BUFFER_SIZE 0x8000
+extern uint8_t usb_samp_buffer[USB_SAMP_BUFFER_SIZE];
 
 static int rx_samples(const unsigned int num_samples, uint32_t max_cycles)
 {
@@ -115,10 +115,10 @@ bool fpga_sgpio_selftest(void)
 	fpga_set_prbs_enable(&fpga, false);
 
 	// Generate sequence from first value and compare.
-	bool seq_in_sync = (usb_bulk_buffer[0] != 0);
-	uint8_t seq = lfsr_advance(usb_bulk_buffer[0]);
+	bool seq_in_sync = (usb_samp_buffer[0] != 0);
+	uint8_t seq = lfsr_advance(usb_samp_buffer[0]);
 	for (int i = 1; i < 512; ++i) {
-		if (usb_bulk_buffer[i] != seq) {
+		if (usb_samp_buffer[i] != seq) {
 			seq_in_sync = false;
 			break;
 		}
@@ -189,7 +189,7 @@ bool fpga_if_xcvr_selftest(void)
 		return false;
 	}
 
-	const size_t num_samples = USB_BULK_BUFFER_SIZE / 2;
+	const size_t num_samples = USB_SAMP_BUFFER_SIZE / 2;
 
 	// Set common RX path and gateware settings for the measurements.
 	fpga_set_tx_nco_pstep(&fpga, 64);    // NCO phase increment
@@ -206,7 +206,7 @@ bool fpga_if_xcvr_selftest(void)
 		timeout = true;
 	}
 	measure_tone(
-		(int8_t*) usb_bulk_buffer,
+		(int8_t*) usb_samp_buffer,
 		num_samples,
 		&selftest.xcvr_measurements[0]);
 
@@ -217,7 +217,7 @@ bool fpga_if_xcvr_selftest(void)
 		timeout = true;
 	}
 	measure_tone(
-		(int8_t*) usb_bulk_buffer,
+		(int8_t*) usb_samp_buffer,
 		num_samples,
 		&selftest.xcvr_measurements[1]);
 
@@ -230,7 +230,7 @@ bool fpga_if_xcvr_selftest(void)
 		timeout = true;
 	}
 	measure_tone(
-		(int8_t*) usb_bulk_buffer,
+		(int8_t*) usb_samp_buffer,
 		num_samples,
 		&selftest.xcvr_measurements[2]);
 
@@ -241,7 +241,7 @@ bool fpga_if_xcvr_selftest(void)
 		timeout = true;
 	}
 	measure_tone(
-		(int8_t*) usb_bulk_buffer,
+		(int8_t*) usb_samp_buffer,
 		num_samples,
 		&selftest.xcvr_measurements[3]);
 

firmware/common/usb.h

@@ -31,6 +31,8 @@
 
 #include "usb_type.h"
 
+usb_queue_head_t* usb_queue_head(const uint_fast8_t endpoint_address);
+
 void usb_peripheral_reset(void);
 void usb_phy_enable(void);
 

firmware/hackrf_usb/hackrf_usb.c

@@ -183,6 +183,7 @@ static usb_request_handler_fn vendor_request_handler[] = {
 	usb_vendor_request_test_rtc_osc,
 	usb_vendor_request_write_radio_reg,
 	usb_vendor_request_read_radio_reg,
+	usb_vendor_request_get_buffer_size,
 };
 
 static const uint32_t vendor_request_handler_count =

firmware/hackrf_usb/usb_api_sweep.c

@@ -40,7 +40,7 @@
 
 #include "usb_api_sweep.h"
 #include "usb_api_transceiver.h"
-#include "usb_bulk_buffer.h"
+#include "usb_buffer.h"
 #include "usb_endpoint.h"
 
 #define MIN(x, y)        ((x) < (y) ? (x) : (y))
@@ -207,7 +207,7 @@ void sweep_mode(uint32_t seq)
 		m0_state.next_mode = M0_MODE_RX;
 
 		// Write metadata to buffer.
-		buffer = &usb_bulk_buffer[phase * 0x4000];
+		buffer = &usb_samp_buffer[phase * 0x4000];
 		*buffer = 0x7f;
 		*(buffer + 1) = 0x7f;
 		*(buffer + 2) = sweep_freq & 0xff;