From eb13d4ab04d9cef1c0b6f351f50fe7f3e39dbdb2 Mon Sep 17 00:00:00 2001
From: logicog <git@logicog.de>
Date: Mon, 2 Mar 2026 07:38:00 +0100
Subject: [PATCH] Add iniital implementation of bandwidth control

---
 rtl837x_bandwidth.c | 108 ++++++++++++++++++++++++++++++++++++++++++++
 rtl837x_bandwidth.h |  14 ++++++
 2 files changed, 122 insertions(+)
 create mode 100644 rtl837x_bandwidth.c
 create mode 100644 rtl837x_bandwidth.h

diff --git a/rtl837x_bandwidth.c b/rtl837x_bandwidth.c
new file mode 100644
index 0000000..9ab047b
--- /dev/null
+++ b/rtl837x_bandwidth.c
@@ -0,0 +1,108 @@
+// #define REGDBG
+// #define DEBUG
+
+#include "rtl837x_common.h"
+#include "rtl837x_sfr.h"
+#include "rtl837x_regs.h"
+#include "rtl837x_bandwidth.h"
+#include "machine.h"
+
+#pragma codeseg BANK2
+#pragma constseg BANK2
+
+extern __xdata uint8_t sfr_data[4];
+
+void bandwidth_setup(void) __banked
+{
+	print_string("bandwidth_setup called\n");
+	// Exclude all packets possibly for the CPU port, but do not include bypassed packets or Inter-Frame-Gap into bandwidth
+	REG_SET(RTL837X_IGBW_CTRL, IGBW_ADM_DHCP | IGBW_ADM_ARPREQ | IGBW_ADM_RMA | IGBW_ADM_BPDU | IGBW_ADM_RTKPKT | IGBW_ADM_IGMP);
+
+	// We do not count IFG for Egress and allways allow CPU-traffic
+	REG_SET(RTL837X_EGBW_CTRL, EGBW_CPUMODE);
+
+	print_string("RTL837X_IGBW_CTRL: "); print_reg(RTL837X_IGBW_CTRL); write_char('\n');
+	print_string("RTL837X_EGBW_CTRL: "); print_reg(RTL837X_EGBW_CTRL); write_char('\n');
+	print_string("bandwidth_setup done\n");
+}
+
+
+/*
+ * Set the ingress bandwidth
+ * bw: Bandwidth in kb
+ */
+void bandwidth_ingress_set(uint8_t port, __xdata uint32_t bw) __banked
+{
+	__xdata uint8_t * __xdata bwptr = &bw;
+
+	print_string("bandwidth_ingress_set called, port "); print_byte(port); write_char('\n');
+	sfr_data[0] = 0;
+	sfr_data[1] = 0x10 | (*(bwptr + 2) >> 4);  // Set bit 20 to enable ingress bandwidth control
+	sfr_data[2] = (*(bwptr + 2) << 4) | (*(bwptr + 1) >> 4);
+	sfr_data[3] = (*(bwptr) >> 4) | (*(bwptr + 1) << 4);
+	reg_write_m(RTL837X_IGBW_PORT_CTRL + port * 4);
+
+	// We enable Flow Control instead of just dropping packets
+	reg_bit_set(RTL837X_IGBW_PORT_FC_CTRL, port);
+	print_string("RTL837X_IGBW_PORT_FC_CTRL:"); print_reg(RTL837X_IGBW_PORT_FC_CTRL); write_char('\n');
+}
+
+
+void bandwidth_ingress_drop(uint8_t port) __banked
+{
+	reg_bit_clear(RTL837X_IGBW_PORT_FC_CTRL, port);
+	print_string("RTL837X_IGBW_PORT_FC_CTRL:"); print_reg(RTL837X_IGBW_PORT_FC_CTRL); write_char('\n');
+}
+
+
+void bandwidth_ingress_disable(uint8_t port) __banked
+{
+	print_string("Ingress bandwidth limit disabled, port "); print_byte(port); write_char('\n');
+	REG_SET(RTL837X_IGBW_PORT_CTRL + port * 4, 0x0fffff);
+}
+
+
+void bandwidth_egress_set(uint8_t port, __xdata uint32_t bw) __banked
+{
+	__xdata uint8_t * __xdata bwptr = &bw;
+
+	print_string("bandwidth_egress_set called, port "); print_byte(port); write_char('\n');
+	sfr_data[0] = 0;
+	sfr_data[1] = 0x10 | (*(bwptr + 2) >> 4);  // Set bit 20 to enable egress bandwidth control
+	sfr_data[2] = (*(bwptr + 2) << 4) | (*(bwptr + 1) >> 4);
+	sfr_data[3] = (*(bwptr) >> 4) | (*(bwptr + 1) << 4);
+	reg_write_m(RTL837X_EGBW_PORT_CTRL + port * 1024);
+}
+
+
+void bandwidth_egress_disable(uint8_t port) __banked
+{
+	print_string("Egress bandwidth limit disabled, port "); print_byte(port); write_char('\n');
+	REG_SET(RTL837X_EGBW_PORT_CTRL + port * 1024, 0x0fffff);
+}
+
+
+void bandwidth_status(uint8_t port) __banked
+{
+	print_string("ingress: ");
+	reg_read_m(RTL837X_IGBW_PORT_CTRL + port * 4);
+	if (sfr_data[1] & 0x10) {
+		print_string("enabled: ");
+		sfr_data[1] &= 0xef;
+		print_sfr_data();
+		write_char('\n');
+	} else {
+		print_string("disabled\n");
+	}
+
+	print_string("egress: ");
+	reg_read_m(RTL837X_EGBW_PORT_CTRL + port * 1024);
+	if (sfr_data[1] & 0x10) {
+		print_string("enabled: ");
+		sfr_data[1] &= 0xef;
+		print_sfr_data();
+		write_char('\n');
+	} else {
+		print_string("disabled\n");
+	}
+}
diff --git a/rtl837x_bandwidth.h b/rtl837x_bandwidth.h
new file mode 100644
index 0000000..d704dc2
--- /dev/null
+++ b/rtl837x_bandwidth.h
@@ -0,0 +1,14 @@
+#ifndef _RTL837X_BANDWIDTH_H_
+#define _RTL837X_BANDWIDTH_H_
+
+#include <stdint.h>
+
+void bandwidth_setup(void) __banked;
+void bandwidth_ingress_set(uint8_t port, __xdata uint32_t bw) __banked;
+void bandwidth_ingress_disable(uint8_t port) __banked;
+void bandwidth_ingress_drop(uint8_t port) __banked;
+void bandwidth_egress_set(uint8_t port, __xdata uint32_t bw) __banked;
+void bandwidth_egress_disable(uint8_t port) __banked;
+void bandwidth_status(uint8_t port) __banked;
+
+#endif