From e5110dfce1f2c84757882dece9b646f3093f1d97 Mon Sep 17 00:00:00 2001 From: Graham Sanderson Date: Tue, 26 Oct 2021 13:45:32 -0500 Subject: [PATCH] add docs for pio_instructions.h (#624) Co-authored-by: Andrew Scheller --- .../include/hardware/pio_instructions.h | 357 ++++++++++++++++-- .../pico_stdio_usb/include/pico/stdio_usb.h | 4 +- 2 files changed, 333 insertions(+), 28 deletions(-) diff --git a/src/rp2_common/hardware_pio/include/hardware/pio_instructions.h b/src/rp2_common/hardware_pio/include/hardware/pio_instructions.h index 07df65b..3662135 100644 --- a/src/rp2_common/hardware_pio/include/hardware/pio_instructions.h +++ b/src/rp2_common/hardware_pio/include/hardware/pio_instructions.h @@ -9,7 +9,18 @@ #include "pico.h" -// PICO_CONFIG: PARAM_ASSERTIONS_ENABLED_PIO_INSTRUCTIONS, Enable/disable assertions in the PIO instructions, type=bool, default=0, group=hardware_pio +/** \brief PIO instruction encoding + * \defgroup pio_instructions pio_instructions + * \ingroup hardware_pio + * + * Functions for generating PIO instruction encodings programmatically. In debug builds + *`PARAM_ASSERTIONS_ENABLED_PIO_INSTRUCTIONS` can be set to 1 to enable validation of encoding function + * parameters. + * + * For fuller descriptions of the instructions in question see the "RP2040 Datasheet" + */ + +// PICO_CONFIG: PARAM_ASSERTIONS_ENABLED_PIO_INSTRUCTIONS, Enable/disable assertions in the PIO instructions, type=bool, default=0, group=pio_instructions #ifndef PARAM_ASSERTIONS_ENABLED_PIO_INSTRUCTIONS #define PARAM_ASSERTIONS_ENABLED_PIO_INSTRUCTIONS 0 #endif @@ -44,6 +55,12 @@ enum pio_instr_bits { #define _PIO_INVALID_MOV_DEST 0u #endif +/*! \brief Enumeration of values to pass for source/destination args for instruction encoding functions + * \ingroup pio_instructions + * + * \note Not all values are suitable for all functions. Validity is only checked in debug mode when + * `PARAM_ASSERTIONS_ENABLED_PIO_INSTRUCTIONS` is 1 + */ enum pio_src_dest { pio_pins = 0u, pio_x = 1u, @@ -58,11 +75,11 @@ enum pio_src_dest { pio_exec_out = 7u | _PIO_INVALID_IN_SRC | _PIO_INVALID_SET_DEST | _PIO_INVALID_MOV_SRC | _PIO_INVALID_MOV_DEST, }; -inline static uint _pio_major_instr_bits(uint instr) { +static inline uint _pio_major_instr_bits(uint instr) { return instr & 0xe000u; } -inline static uint _pio_encode_instr_and_args(enum pio_instr_bits instr_bits, uint arg1, uint arg2) { +static inline uint _pio_encode_instr_and_args(enum pio_instr_bits instr_bits, uint arg1, uint arg2) { valid_params_if(PIO_INSTRUCTIONS, arg1 <= 0x7); #if PARAM_ASSERTIONS_ENABLED(PIO_INSTRUCTIONS) uint32_t major = _pio_major_instr_bits(instr_bits); @@ -75,100 +92,388 @@ inline static uint _pio_encode_instr_and_args(enum pio_instr_bits instr_bits, ui return instr_bits | (arg1 << 5u) | (arg2 & 0x1fu); } -inline static uint _pio_encode_instr_and_src_dest(enum pio_instr_bits instr_bits, enum pio_src_dest dest, uint value) { +static inline uint _pio_encode_instr_and_src_dest(enum pio_instr_bits instr_bits, enum pio_src_dest dest, uint value) { return _pio_encode_instr_and_args(instr_bits, dest & 7u, value); } -inline static uint pio_encode_delay(uint cycles) { +/*! \brief Encode just the delay slot bits of an instruction + * \ingroup pio_instructions + * + * \note This function does not return a valid instruction encoding; instead it returns an encoding of the delay + * slot suitable for `OR`ing with the result of an encoding function for an actual instruction. Care should be taken when + * combining the results of this function with the results of \ref pio_encode_sideset and \ref pio_encode_sideset_opt + * as they share the same bits within the instruction encoding. + * + * \param cycles the number of cycles 0-31 (or less if side set is being used) + * \return the delay slot bits to be ORed with an instruction encoding + */ +static inline uint pio_encode_delay(uint cycles) { // note that the maximum cycles will be smaller if sideset_bit_count > 0 valid_params_if(PIO_INSTRUCTIONS, cycles <= 0x1f); return cycles << 8u; } -inline static uint pio_encode_sideset(uint sideset_bit_count, uint value) { +/*! \brief Encode just the side set bits of an instruction (in non optional side set mode) + * \ingroup pio_instructions + * + * \note This function does not return a valid instruction encoding; instead it returns an encoding of the side set bits + * suitable for `OR`ing with the result of an encoding function for an actual instruction. Care should be taken when + * combining the results of this function with the results of \ref pio_encode_delay as they share the same bits + * within the instruction encoding. + * + * \param sideset_bit_count number of side set bits as would be specified via `.sideset` in pioasm + * \param value the value to sideset on the pins + * \return the side set bits to be ORed with an instruction encoding + */ +static inline uint pio_encode_sideset(uint sideset_bit_count, uint value) { valid_params_if(PIO_INSTRUCTIONS, sideset_bit_count >= 1 && sideset_bit_count <= 5); valid_params_if(PIO_INSTRUCTIONS, value <= ((1u << sideset_bit_count) - 1)); return value << (13u - sideset_bit_count); } -inline static uint pio_encode_sideset_opt(uint sideset_bit_count, uint value) { +/*! \brief Encode just the side set bits of an instruction (in optional -`opt` side set mode) + * \ingroup pio_instructions + * + * \note This function does not return a valid instruction encoding; instead it returns an encoding of the side set bits + * suitable for `OR`ing with the result of an encoding function for an actual instruction. Care should be taken when + * combining the results of this function with the results of \ref pio_encode_delay as they share the same bits + * within the instruction encoding. + * + * \param sideset_bit_count number of side set bits as would be specified via `.sideset opt` in pioasm + * \param value the value to sideset on the pins + * \return the side set bits to be ORed with an instruction encoding + */ +static inline uint pio_encode_sideset_opt(uint sideset_bit_count, uint value) { valid_params_if(PIO_INSTRUCTIONS, sideset_bit_count >= 1 && sideset_bit_count <= 4); valid_params_if(PIO_INSTRUCTIONS, value <= ((1u << sideset_bit_count) - 1)); return 0x1000u | value << (12u - sideset_bit_count); } -inline static uint pio_encode_jmp(uint addr) { +/*! \brief Encode an unconditional JMP instruction + * \ingroup pio_instructions + * + * This is the equivalent of `JMP ` + * + * \param addr The target address 0-31 (an absolute address within the PIO instruction memory) + * \return The instruction encoding with 0 delay and no side set value + * \see pio_encode_delay, pio_encode_sideset, pio_encode_sideset_opt + */ +static inline uint pio_encode_jmp(uint addr) { return _pio_encode_instr_and_args(pio_instr_bits_jmp, 0, addr); } -inline static uint _pio_encode_irq(bool relative, uint irq) { +/*! \brief Encode a conditional JMP if scratch X zero instruction + * \ingroup pio_instructions + * + * This is the equivalent of `JMP !X ` + * + * \param addr The target address 0-31 (an absolute address within the PIO instruction memory) + * \return The instruction encoding with 0 delay and no side set value + * \see pio_encode_delay, pio_encode_sideset, pio_encode_sideset_opt + */ +static inline uint pio_encode_jmp_not_x(uint addr) { + return _pio_encode_instr_and_args(pio_instr_bits_jmp, 1, addr); +} + +/*! \brief Encode a conditional JMP if scratch X non-zero (and post-decrement X) instruction + * \ingroup pio_instructions + * + * This is the equivalent of `JMP X-- ` + * + * \param addr The target address 0-31 (an absolute address within the PIO instruction memory) + * \return The instruction encoding with 0 delay and no side set value + * \see pio_encode_delay, pio_encode_sideset, pio_encode_sideset_opt + */ +static inline uint pio_encode_jmp_x_dec(uint addr) { + return _pio_encode_instr_and_args(pio_instr_bits_jmp, 2, addr); +} + +/*! \brief Encode a conditional JMP if scratch Y zero instruction + * \ingroup pio_instructions + * + * This is the equivalent of `JMP !Y ` + * + * \param addr The target address 0-31 (an absolute address within the PIO instruction memory) + * \return The instruction encoding with 0 delay and no side set value + * \see pio_encode_delay, pio_encode_sideset, pio_encode_sideset_opt + */ +static inline uint pio_encode_jmp_not_y(uint addr) { + return _pio_encode_instr_and_args(pio_instr_bits_jmp, 3, addr); +} + +/*! \brief Encode a conditional JMP if scratch Y non-zero (and post-decrement Y) instruction + * \ingroup pio_instructions + * + * This is the equivalent of `JMP Y-- ` + * + * \param addr The target address 0-31 (an absolute address within the PIO instruction memory) + * \return The instruction encoding with 0 delay and no side set value + * \see pio_encode_delay, pio_encode_sideset, pio_encode_sideset_opt + */ +static inline uint pio_encode_jmp_y_dec(uint addr) { + return _pio_encode_instr_and_args(pio_instr_bits_jmp, 4, addr); +} + +/*! \brief Encode a conditional JMP if scratch X not equal scratch Y instruction + * \ingroup pio_instructions + * + * This is the equivalent of `JMP X!=Y ` + * + * \param addr The target address 0-31 (an absolute address within the PIO instruction memory) + * \return The instruction encoding with 0 delay and no side set value + * \see pio_encode_delay, pio_encode_sideset, pio_encode_sideset_opt + */ +static inline uint pio_encode_jmp_x_ne_y(uint addr) { + return _pio_encode_instr_and_args(pio_instr_bits_jmp, 5, addr); +} + +/*! \brief Encode a conditional JMP if input pin high instruction + * \ingroup pio_instructions + * + * This is the equivalent of `JMP PIN ` + * + * \param addr The target address 0-31 (an absolute address within the PIO instruction memory) + * \return The instruction encoding with 0 delay and no side set value + * \see pio_encode_delay, pio_encode_sideset, pio_encode_sideset_opt + */ +static inline uint pio_encode_jmp_pin(uint addr) { + return _pio_encode_instr_and_args(pio_instr_bits_jmp, 6, addr); +} + +/*! \brief Encode a conditional JMP if output shift register not empty instruction + * \ingroup pio_instructions + * + * This is the equivalent of `JMP !OSRE ` + * + * \param addr The target address 0-31 (an absolute address within the PIO instruction memory) + * \return The instruction encoding with 0 delay and no side set value + * \see pio_encode_delay, pio_encode_sideset, pio_encode_sideset_opt + */ +static inline uint pio_encode_jmp_not_osre(uint addr) { + return _pio_encode_instr_and_args(pio_instr_bits_jmp, 7, addr); +} + +static inline uint _pio_encode_irq(bool relative, uint irq) { valid_params_if(PIO_INSTRUCTIONS, irq <= 7); return (relative ? 0x10u : 0x0u) | irq; } -inline static uint pio_encode_wait_gpio(bool polarity, uint pin) { - return _pio_encode_instr_and_args(pio_instr_bits_wait, 0u | (polarity ? 4u : 0u), pin); +/*! \brief Encode a WAIT for GPIO pin instruction + * \ingroup pio_instructions + * + * This is the equivalent of `WAIT GPIO ` + * + * \param polarity true for `WAIT 1`, false for `WAIT 0` + * \param gpio The real GPIO number 0-31 + * \return The instruction encoding with 0 delay and no side set value + * \see pio_encode_delay, pio_encode_sideset, pio_encode_sideset_opt + */ +static inline uint pio_encode_wait_gpio(bool polarity, uint gpio) { + return _pio_encode_instr_and_args(pio_instr_bits_wait, 0u | (polarity ? 4u : 0u), gpio); } -inline static uint pio_encode_wait_pin(bool polarity, uint pin) { +/*! \brief Encode a WAIT for pin instruction + * \ingroup pio_instructions + * + * This is the equivalent of `WAIT PIN ` + * + * \param polarity true for `WAIT 1`, false for `WAIT 0` + * \param pin The pin number 0-31 relative to the executing SM's input pin mapping + * \return The instruction encoding with 0 delay and no side set value + * \see pio_encode_delay, pio_encode_sideset, pio_encode_sideset_opt + */ +static inline uint pio_encode_wait_pin(bool polarity, uint pin) { return _pio_encode_instr_and_args(pio_instr_bits_wait, 1u | (polarity ? 4u : 0u), pin); } -inline static uint pio_encode_wait_irq(bool polarity, bool relative, uint irq) { +/*! \brief Encode a WAIT for IRQ instruction + * \ingroup pio_instructions + * + * This is the equivalent of `WAIT IRQ ` + * + * \param polarity true for `WAIT 1`, false for `WAIT 0` + * \param relative true for a `WAIT IRQ REL`, false for regular `WAIT IRQ ` + * \param irq the irq number 0-7 + * \return The instruction encoding with 0 delay and no side set value + * \see pio_encode_delay, pio_encode_sideset, pio_encode_sideset_opt + */ +static inline uint pio_encode_wait_irq(bool polarity, bool relative, uint irq) { valid_params_if(PIO_INSTRUCTIONS, irq <= 7); return _pio_encode_instr_and_args(pio_instr_bits_wait, 2u | (polarity ? 4u : 0u), _pio_encode_irq(relative, irq)); } -inline static uint pio_encode_in(enum pio_src_dest src, uint value) { +/*! \brief Encode an IN instruction + * \ingroup pio_instructions + * + * This is the equivalent of `IN , ` + * + * \param src The source to take data from + * \param count The number of bits 1-32 + * \return The instruction encoding with 0 delay and no side set value + * \see pio_encode_delay, pio_encode_sideset, pio_encode_sideset_opt + */ +static inline uint pio_encode_in(enum pio_src_dest src, uint count) { valid_params_if(PIO_INSTRUCTIONS, !(src & _PIO_INVALID_IN_SRC)); - return _pio_encode_instr_and_src_dest(pio_instr_bits_in, src, value); + return _pio_encode_instr_and_src_dest(pio_instr_bits_in, src, count); } -inline static uint pio_encode_out(enum pio_src_dest dest, uint value) { +/*! \brief Encode an OUT instruction + * \ingroup pio_instructions + * + * This is the equivalent of `OUT , ` + * + * \param dest The destination to write data to + * \param count The number of bits 1-32 + * \return The instruction encoding with 0 delay and no side set value + * \see pio_encode_delay, pio_encode_sideset, pio_encode_sideset_opt + */ +static inline uint pio_encode_out(enum pio_src_dest dest, uint count) { valid_params_if(PIO_INSTRUCTIONS, !(dest & _PIO_INVALID_OUT_DEST)); - return _pio_encode_instr_and_src_dest(pio_instr_bits_out, dest, value); + return _pio_encode_instr_and_src_dest(pio_instr_bits_out, dest, count); } -inline static uint pio_encode_push(bool if_full, bool block) { +/*! \brief Encode a PUSH instruction + * \ingroup pio_instructions + * + * This is the equivalent of `PUSH , ` + * + * \param if_full true for `PUSH IF_FULL ...`, false for `PUSH ...` + * \param block true for `PUSH ... BLOCK`, false for `PUSH ...` + * \return The instruction encoding with 0 delay and no side set value + * \see pio_encode_delay, pio_encode_sideset, pio_encode_sideset_opt + */ +static inline uint pio_encode_push(bool if_full, bool block) { return _pio_encode_instr_and_args(pio_instr_bits_push, (if_full ? 2u : 0u) | (block ? 1u : 0u), 0); } -inline static uint pio_encode_pull(bool if_empty, bool block) { +/*! \brief Encode a PULL instruction + * \ingroup pio_instructions + * + * This is the equivalent of `PULL , ` + * + * \param if_empty true for `PULL IF_EMPTY ...`, false for `PULL ...` + * \param block true for `PULL ... BLOCK`, false for `PULL ...` + * \return The instruction encoding with 0 delay and no side set value + * \see pio_encode_delay, pio_encode_sideset, pio_encode_sideset_opt + */ +static inline uint pio_encode_pull(bool if_empty, bool block) { return _pio_encode_instr_and_args(pio_instr_bits_pull, (if_empty ? 2u : 0u) | (block ? 1u : 0u), 0); } -inline static uint pio_encode_mov(enum pio_src_dest dest, enum pio_src_dest src) { +/*! \brief Encode a MOV instruction + * \ingroup pio_instructions + * + * This is the equivalent of `MOV , ` + * + * \param dest The destination to write data to + * \param src The source to take data from + * \return The instruction encoding with 0 delay and no side set value + * \see pio_encode_delay, pio_encode_sideset, pio_encode_sideset_opt + */ +static inline uint pio_encode_mov(enum pio_src_dest dest, enum pio_src_dest src) { valid_params_if(PIO_INSTRUCTIONS, !(dest & _PIO_INVALID_MOV_DEST)); valid_params_if(PIO_INSTRUCTIONS, !(src & _PIO_INVALID_MOV_SRC)); return _pio_encode_instr_and_src_dest(pio_instr_bits_mov, dest, src & 7u); } -inline static uint pio_encode_mov_not(enum pio_src_dest dest, enum pio_src_dest src) { +/*! \brief Encode a MOV instruction with bit invert + * \ingroup pio_instructions + * + * This is the equivalent of `MOV , ~` + * + * \param dest The destination to write inverted data to + * \param src The source to take data from + * \return The instruction encoding with 0 delay and no side set value + * \see pio_encode_delay, pio_encode_sideset, pio_encode_sideset_opt + */ +static inline uint pio_encode_mov_not(enum pio_src_dest dest, enum pio_src_dest src) { valid_params_if(PIO_INSTRUCTIONS, !(dest & _PIO_INVALID_MOV_DEST)); valid_params_if(PIO_INSTRUCTIONS, !(src & _PIO_INVALID_MOV_SRC)); return _pio_encode_instr_and_src_dest(pio_instr_bits_mov, dest, (1u << 3u) | (src & 7u)); } -inline static uint pio_encode_mov_reverse(enum pio_src_dest dest, enum pio_src_dest src) { +/*! \brief Encode a MOV instruction with bit reverse + * \ingroup pio_instructions + * + * This is the equivalent of `MOV , ::` + * + * \param dest The destination to write bit reversed data to + * \param src The source to take data from + * \return The instruction encoding with 0 delay and no side set value + * \see pio_encode_delay, pio_encode_sideset, pio_encode_sideset_opt + */ +static inline uint pio_encode_mov_reverse(enum pio_src_dest dest, enum pio_src_dest src) { valid_params_if(PIO_INSTRUCTIONS, !(dest & _PIO_INVALID_MOV_DEST)); valid_params_if(PIO_INSTRUCTIONS, !(src & _PIO_INVALID_MOV_SRC)); return _pio_encode_instr_and_src_dest(pio_instr_bits_mov, dest, (2u << 3u) | (src & 7u)); } -inline static uint pio_encode_irq_set(bool relative, uint irq) { +/*! \brief Encode a IRQ SET instruction + * \ingroup pio_instructions + * + * This is the equivalent of `IRQ SET ` + * + * \param relative true for a `IRQ SET REL`, false for regular `IRQ SET ` + * \param irq the irq number 0-7 + * \return The instruction encoding with 0 delay and no side set value + * \see pio_encode_delay, pio_encode_sideset, pio_encode_sideset_opt + */ +static inline uint pio_encode_irq_set(bool relative, uint irq) { return _pio_encode_instr_and_args(pio_instr_bits_irq, 0, _pio_encode_irq(relative, irq)); } -inline static uint pio_encode_irq_clear(bool relative, uint irq) { +/*! \brief Encode a IRQ WAIT instruction + * \ingroup pio_instructions + * + * This is the equivalent of `IRQ WAIT ` + * + * \param relative true for a `IRQ WAIT REL`, false for regular `IRQ WAIT ` + * \param irq the irq number 0-7 + * \return The instruction encoding with 0 delay and no side set value + * \see pio_encode_delay, pio_encode_sideset, pio_encode_sideset_opt + */ +static inline uint pio_encode_irq_wait(bool relative, uint irq) { + return _pio_encode_instr_and_args(pio_instr_bits_irq, 1, _pio_encode_irq(relative, irq)); +} + +/*! \brief Encode a IRQ CLEAR instruction + * \ingroup pio_instructions + * + * This is the equivalent of `IRQ CLEAR ` + * + * \param relative true for a `IRQ CLEAR REL`, false for regular `IRQ CLEAR ` + * \param irq the irq number 0-7 + * \return The instruction encoding with 0 delay and no side set value + * \see pio_encode_delay, pio_encode_sideset, pio_encode_sideset_opt + */ +static inline uint pio_encode_irq_clear(bool relative, uint irq) { return _pio_encode_instr_and_args(pio_instr_bits_irq, 2, _pio_encode_irq(relative, irq)); } -inline static uint pio_encode_set(enum pio_src_dest dest, uint value) { +/*! \brief Encode a SET instruction + * \ingroup pio_instructions + * + * This is the equivalent of `SET , ` + * + * \param dest The destination to apply the value to + * \param value The value 0-31 + * \return The instruction encoding with 0 delay and no side set value + * \see pio_encode_delay, pio_encode_sideset, pio_encode_sideset_opt + */ +static inline uint pio_encode_set(enum pio_src_dest dest, uint value) { valid_params_if(PIO_INSTRUCTIONS, !(dest & _PIO_INVALID_SET_DEST)); return _pio_encode_instr_and_src_dest(pio_instr_bits_set, dest, value); } -inline static uint pio_encode_nop(void) { +/*! \brief Encode a NOP instruction + * \ingroup pio_instructions + * + * This is the equivalent of `NOP` which is itself encoded as `MOV y, y` + * + * \return The instruction encoding with 0 delay and no side set value + * \see pio_encode_delay, pio_encode_sideset, pio_encode_sideset_opt + */ +static inline uint pio_encode_nop(void) { return pio_encode_mov(pio_y, pio_y); } diff --git a/src/rp2_common/pico_stdio_usb/include/pico/stdio_usb.h b/src/rp2_common/pico_stdio_usb/include/pico/stdio_usb.h index db63142..2aeb647 100644 --- a/src/rp2_common/pico_stdio_usb/include/pico/stdio_usb.h +++ b/src/rp2_common/pico_stdio_usb/include/pico/stdio_usb.h @@ -54,12 +54,12 @@ #define PICO_STDIO_USB_RESET_MAGIC_BAUD_RATE 1200 #endif -// PICO_CONFIG: PICO_STDIO_USB_CONNECT_WAIT_TIMEOUT_MS, Maximum number of milliseconds to wait during initialization for a CDC connection from the host (negative means indefinite) before returning, default=0, group=pico_stdio_usb +// PICO_CONFIG: PICO_STDIO_USB_CONNECT_WAIT_TIMEOUT_MS, Maximum number of milliseconds to wait during initialization for a CDC connection from the host (negative means indefinite) during initialization, default=0, group=pico_stdio_usb #ifndef PICO_STDIO_USB_CONNECT_WAIT_TIMEOUT_MS #define PICO_STDIO_USB_CONNECT_WAIT_TIMEOUT_MS 0 #endif -// PICO_CONFIG: PICO_STDIO_USB_POST_CONNECT_WAIT_DELAY_MS, Number of milliseconds to wait during initialization after a host CDC connection is detected before returning (some host terminals seem to sometimes lose transmissions sent right after connection), default=50, group=pico_stdio_usb +// PICO_CONFIG: PICO_STDIO_USB_POST_CONNECT_WAIT_DELAY_MS, Number of extra milliseconds to wait when using PICO_STDIO_USB_CONNECT_WAIT_TIMEOUT_MS after a host CDC connection is detected (some host terminals seem to sometimes lose transmissions sent right after connection), default=50, group=pico_stdio_usb #ifndef PICO_STDIO_USB_POST_CONNECT_WAIT_DELAY_MS #define PICO_STDIO_USB_POST_CONNECT_WAIT_DELAY_MS 50 #endif