@@ 0,0 1,271 @@
+// Copyright 2022 Marek Kraus (@gamelaster)
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include "quantum.h"
+
+#include "hardware/pio.h"
+#include "hardware/clocks.h"
+#include "ps2.h"
+#include "print.h"
+
+#if !defined(MCU_RP)
+# error PIO Driver is only available for Raspberry Pi 2040 MCUs!
+#endif
+
+#if defined(PS2_ENABLE)
+# if defined(PS2_MOUSE_ENABLE)
+# if !defined(PS2_MOUSE_USE_REMOTE_MODE)
+# define BUFFERED_MODE_ENABLE
+# endif
+# else // PS2 Keyboard
+# define BUFFERED_MODE_ENABLE
+# endif
+#endif
+
+#if PS2_DATA_PIN + 1 != PS2_CLOCK_PIN
+# error PS/2 Clock pin must be followed by data pin!
+#endif
+
+static inline void pio_serve_interrupt(void);
+
+#if defined(PS2_PIO_USE_PIO1)
+static const PIO pio = pio1;
+
+OSAL_IRQ_HANDLER(RP_PIO1_IRQ_0_HANDLER) {
+ OSAL_IRQ_PROLOGUE();
+ pio_serve_interrupt();
+ OSAL_IRQ_EPILOGUE();
+}
+#else
+static const PIO pio = pio0;
+
+OSAL_IRQ_HANDLER(RP_PIO0_IRQ_0_HANDLER) {
+ OSAL_IRQ_PROLOGUE();
+ pio_serve_interrupt();
+ OSAL_IRQ_EPILOGUE();
+}
+#endif
+
+#define PS2_WRAP_TARGET 0
+#define PS2_WRAP 20
+
+// clang-format off
+static const uint16_t ps2_program_instructions[] = {
+ // .wrap_target
+ 0x00c7, // 0: jmp pin, 7
+ 0xe02a, // 1: set x, 10
+ 0x2021, // 2: wait 0 pin, 1
+ 0x4001, // 3: in pins, 1
+ 0x20a1, // 4: wait 1 pin, 1
+ 0x0042, // 5: jmp x--, 2
+ 0x0000, // 6: jmp 0
+ 0x00e9, // 7: jmp !osre, 9
+ 0x0000, // 8: jmp 0
+ 0xff81, // 9: set pindirs, 1 [31]
+ 0xe280, // 10: set pindirs, 0 [2]
+ 0xe082, // 11: set pindirs, 2
+ 0x2021, // 12: wait 0 pin, 1
+ 0xe029, // 13: set x, 9
+ 0x6081, // 14: out pindirs, 1
+ 0x20a1, // 15: wait 1 pin, 1
+ 0x2021, // 16: wait 0 pin, 1
+ 0x004e, // 17: jmp x--, 14
+ 0xe083, // 18: set pindirs, 3
+ 0x2021, // 19: wait 0 pin, 1
+ 0x20a1, // 20: wait 1 pin, 1
+ // .wrap
+};
+// clang-format on
+
+static const struct pio_program ps2_program = {
+ .instructions = ps2_program_instructions,
+ .length = 21,
+ .origin = -1,
+};
+
+static int state_machine = -1;
+static thread_reference_t tx_thread = NULL;
+
+#define BUFFER_SIZE 32
+static input_buffers_queue_t pio_rx_queue;
+static __attribute__((aligned(4))) uint8_t pio_rx_buffer[BQ_BUFFER_SIZE(BUFFER_SIZE, sizeof(uint32_t))];
+
+uint8_t ps2_error = PS2_ERR_NONE;
+
+void pio_serve_interrupt(void) {
+ uint32_t irqs = pio->ints0;
+
+ if (irqs & (PIO_IRQ0_INTF_SM0_RXNEMPTY_BITS << state_machine)) {
+ osalSysLockFromISR();
+ uint32_t* frame_buffer = (uint32_t*)ibqGetEmptyBufferI(&pio_rx_queue);
+ if (frame_buffer == NULL) {
+ osalSysUnlockFromISR();
+ return;
+ }
+ *frame_buffer = pio_sm_get(pio, state_machine);
+ ibqPostFullBufferI(&pio_rx_queue, sizeof(uint32_t));
+ osalSysUnlockFromISR();
+ }
+
+ if (irqs & (PIO_IRQ0_INTF_SM0_TXNFULL_BITS << state_machine)) {
+ pio_set_irq0_source_enabled(pio, pis_sm0_tx_fifo_not_full + state_machine, false);
+ osalSysLockFromISR();
+ osalThreadResumeI(&tx_thread, MSG_OK);
+ osalSysUnlockFromISR();
+ }
+}
+
+void ps2_host_init(void) {
+ ibqObjectInit(&pio_rx_queue, false, pio_rx_buffer, sizeof(uint32_t), BUFFER_SIZE, NULL, NULL);
+ uint pio_idx = pio_get_index(pio);
+
+ hal_lld_peripheral_unreset(pio_idx == 0 ? RESETS_ALLREG_PIO0 : RESETS_ALLREG_PIO1);
+
+ state_machine = pio_claim_unused_sm(pio, true);
+ if (state_machine < 0) {
+ dprintln("ERROR: Failed to acquire state machine for PS/2!");
+ ps2_error = PS2_ERR_NODATA;
+ return;
+ }
+
+ uint offset = pio_add_program(pio, &ps2_program);
+
+ pio_sm_config c = pio_get_default_sm_config();
+ sm_config_set_wrap(&c, offset + PS2_WRAP_TARGET, offset + PS2_WRAP);
+
+ // Set pindirs to input (output enable is inverted below)
+ pio_sm_set_consecutive_pindirs(pio, state_machine, PS2_DATA_PIN, 2, true);
+ sm_config_set_clkdiv(&c, (float)clock_get_hz(clk_sys) / (200.0f * KHZ));
+ sm_config_set_set_pins(&c, PS2_DATA_PIN, 2);
+ sm_config_set_out_pins(&c, PS2_DATA_PIN, 1);
+ sm_config_set_out_shift(&c, true, true, 10);
+ sm_config_set_in_shift(&c, true, true, 11);
+ sm_config_set_jmp_pin(&c, PS2_CLOCK_PIN);
+ sm_config_set_in_pins(&c, PS2_DATA_PIN);
+
+ // clang-format off
+ iomode_t pin_mode = PAL_RP_PAD_IE |
+ PAL_RP_GPIO_OE |
+ PAL_RP_PAD_SLEWFAST |
+ PAL_RP_PAD_DRIVE12 |
+ // Invert output enable so that pindirs=1 means input
+ // and indirs=0 means output. This way, out pindirs
+ // works correctly with the open-drain PS/2 interface.
+ // Setting pindirs=1 effectively pulls the line high,
+ // due to the pull-up resistor, while pindirs=0 pulls
+ // the line low.
+ PAL_RP_IOCTRL_OEOVER_DRVINVPERI |
+ (pio_idx == 0 ? PAL_MODE_ALTERNATE_PIO0 : PAL_MODE_ALTERNATE_PIO1);
+ // clang-format on
+
+ palSetLineMode(PS2_DATA_PIN, pin_mode);
+ palSetLineMode(PS2_CLOCK_PIN, pin_mode);
+
+ pio_set_irq0_source_enabled(pio, pis_sm0_rx_fifo_not_empty + state_machine, true);
+ pio_sm_init(pio, state_machine, offset, &c);
+
+#if defined(PS2_PIO_USE_PIO1)
+ nvicEnableVector(RP_PIO1_IRQ_0_NUMBER, CORTEX_MAX_KERNEL_PRIORITY);
+#else
+ nvicEnableVector(RP_PIO0_IRQ_0_NUMBER, CORTEX_MAX_KERNEL_PRIORITY);
+#endif
+
+ pio_sm_set_enabled(pio, state_machine, true);
+}
+
+static int bit_parity(int x) {
+ return !__builtin_parity(x);
+}
+
+uint8_t ps2_host_send(uint8_t data) {
+ uint32_t frame = 0b1000000000;
+ frame = frame | data;
+
+ if (bit_parity(data)) {
+ frame = frame | (1 << 8);
+ }
+
+ pio_sm_put(pio, state_machine, frame);
+
+ msg_t msg = MSG_OK;
+ osalSysLock();
+ while (pio_sm_is_tx_fifo_full(pio, state_machine)) {
+ pio_set_irq0_source_enabled(pio, pis_sm0_tx_fifo_not_full + state_machine, true);
+ msg = osalThreadSuspendTimeoutS(&tx_thread, TIME_MS2I(100));
+ if (msg < MSG_OK) {
+ pio_set_irq0_source_enabled(pio, pis_sm0_tx_fifo_not_full + state_machine, false);
+ ps2_error = PS2_ERR_NODATA;
+ osalSysUnlock();
+ return 0;
+ }
+ }
+ osalSysUnlock();
+
+ return ps2_host_recv_response();
+}
+
+static uint8_t ps2_get_data_from_frame(uint32_t frame) {
+ uint8_t data = (frame >> 22) & 0xFF;
+ uint32_t start_bit = (frame & 0b00000000001000000000000000000000) ? 1 : 0;
+ uint32_t parity_bit = (frame & 0b01000000000000000000000000000000) ? 1 : 0;
+ uint32_t stop_bit = (frame & 0b10000000001000000000000000000000) ? 1 : 0;
+
+ if (start_bit != 0) {
+ ps2_error = PS2_ERR_STARTBIT1;
+ return 0;
+ }
+
+ if (parity_bit != bit_parity(data)) {
+ ps2_error = PS2_ERR_PARITY;
+ return 0;
+ }
+
+ if (stop_bit != 1) {
+ ps2_error = PS2_ERR_STARTBIT2;
+ return 0;
+ }
+
+ return data;
+}
+
+uint8_t ps2_host_recv_response(void) {
+ uint32_t frame = 0;
+ msg_t msg = MSG_OK;
+
+ msg = ibqReadTimeout(&pio_rx_queue, (uint8_t*)&frame, sizeof(uint32_t), TIME_MS2I(100));
+ if (msg < MSG_OK) {
+ ps2_error = PS2_ERR_NODATA;
+ return 0;
+ }
+
+ return ps2_get_data_from_frame(frame);
+}
+
+#ifdef BUFFERED_MODE_ENABLE
+
+bool pbuf_has_data(void) {
+ osalSysLock();
+ bool has_data = !ibqIsEmptyI(&pio_rx_queue);
+ osalSysUnlock();
+ return has_data;
+}
+
+uint8_t ps2_host_recv(void) {
+ uint32_t frame = 0;
+ msg_t msg = MSG_OK;
+
+ uint8_t has_data = pbuf_has_data();
+ if (has_data) {
+ msg = ibqReadTimeout(&pio_rx_queue, (uint8_t*)&frame, sizeof(uint32_t), TIME_MS2I(100));
+ if (msg < MSG_OK) {
+ ps2_error = PS2_ERR_NODATA;
+ return 0;
+ }
+ } else {
+ ps2_error = PS2_ERR_NODATA;
+ }
+
+ return frame != 0 ? ps2_get_data_from_frame(frame) : 0;
+}
+
+#endif