Add piolib

CMakeLists.txt

@@ -10,6 +10,7 @@ add_subdirectory(otpset)
 add_subdirectory(overlaycheck)
 add_subdirectory(ovmerge)
 add_subdirectory(pinctrl)
+add_subdirectory(piolib)
 add_subdirectory(raspinfo)
 add_subdirectory(vcgencmd)
 add_subdirectory(vclog)

README.md

@@ -15,6 +15,7 @@ A collection of scripts and simple applications
 * [pinctrl](pinctrl/) - A more powerful replacement for raspi-gpio, a tool for
     displaying and modifying the GPIO and pin muxing state of a system, bypassing
     the kernel.
+* [piolib](piolib/) - A library for accessing the Pi 5's PIO hardware.
 * [raspinfo](raspinfo/) - A short script to dump information about the Pi. Intended for
     the submission of bug reports.
 * [vclog](vclog/) - A tool to get VideoCore 'assert' or 'msg' logs

piolib/CMakeLists.txt

@@ -0,0 +1,41 @@
+cmake_minimum_required(VERSION 3.10...3.27)
+
+include(GNUInstallDirs)
+
+#set project name
+project(piolib)
+
+set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wall -Wextra -Werror")
+
+if (CMAKE_COMPILER_IS_GNUCC)
+   add_definitions (-ffunction-sections)
+endif ()
+
+add_library (pio OBJECT piolib.c pio_rp1.c)
+target_include_directories(pio PRIVATE .)
+target_link_libraries(pio)
+
+add_executable(piotest piotest.c)
+target_include_directories(piotest PRIVATE .)
+target_link_libraries(piotest pio)
+install(TARGETS piotest RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})
+
+add_executable(piopwm pwm.c)
+target_include_directories(piopwm PRIVATE .)
+target_link_libraries(piopwm pio)
+install(TARGETS piopwm RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})
+
+add_executable(pioseq genseq.c)
+target_include_directories(pioseq PRIVATE .)
+target_link_libraries(pioseq pio)
+install(TARGETS pioseq RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})
+
+add_executable(piows2812 ws2812.c)
+target_include_directories(piows2812 PRIVATE .)
+target_link_libraries(piows2812 pio)
+install(TARGETS piows2812 RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})
+
+add_executable(rp1sm rp1sm.c)
+target_include_directories(rp1sm PRIVATE .)
+target_link_libraries(rp1sm pio)
+install(TARGETS rp1sm RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})

piolib/README.md

@@ -0,0 +1,27 @@
+# piolib
+
+PIOlib/libPIO is a user-space API to the rp1-pio driver, which gives access to the PIO hardware of RP1. It takes the form of a clone of the PICO SDK PIO API, where most of the methods are implemented as RPC calls to RP1. This allows existing PIO code to be run without (much) alteration, but runs into problems when it relies on the PIO state machine and the support code being closely coupled.
+
+To build piolib:
+1. cmake . (or create a build subdirectory and cmake ..)
+2. make
+
+If `ls -l /dev/pio0` reports that the file is not found, you may need to update your Pi 5 firmware to one with PIO support and make sure that you are running a suitably recent kernel.
+If `ls -l /dev/pio0` reports that the file is owned by `root` and group `root`, you should add the following to /etc/udev/rules/99-com.rules:
+```
+SUBSYSTEM=="*-pio", GROUP="gpio", MODE="0660"
+```
+
+Examples:
+
+* piotest:
+    This is the normal WS2812 example LED PIO code, but using DMA to send the data. The optional parameter is the GPIO number to drive; the defailt is 2.
+* piopwm:
+    The PWM example, unmodified except for dynamic SM allocation and a command line parameter to choose the GPIO. The optional parameter is the GPIO number to drive; the default is 4.
+* piows2812:
+    The ws2812 example, unmodified except for dynamic SM allocation and a command line parameter to choose the GPIO. The optional parameter is the GPIO number to drive; the defailt is 2.
+* rp1sm:
+    Show the state of the hardware for a particular SM. The parameter is the number of the state machine to inspect.
+
+Known issues:
+* Blocking operations block the whole RP1 firmware interface until they complete.

piolib/ds18b20.h

@@ -0,0 +1,9 @@
+// Function commands for d218b20 1-Wire temperature sensor 
+// https://www.analog.com/en/products/ds18b20.html
+//
+#define DS18B20_CONVERT_T           0x44
+#define DS18B20_WRITE_SCRATCHPAD    0x4e
+#define DS18B20_READ_SCRATCHPAD     0xbe
+#define DS18B20_COPY_SCRATCHPAD     0x48
+#define DS18B20_RECALL_EE           0xb8
+#define DS18B20_READ_POWER_SUPPLY   0xb4

piolib/genseq.c

@@ -0,0 +1,68 @@
+/**
+ * Copyright (c) 2020 Raspberry Pi (Trading) Ltd.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "pico/stdlib.h"
+#include "hardware/pio.h"
+#include "genseq.pio.h"
+
+#define DATA_WORDS 1024
+
+int main(int argc, const char **argv) {
+    uint32_t databuf[DATA_WORDS];
+    bool use_dma = true;
+    int ret = 0;
+    int i, j;
+    stdio_init_all();
+
+    PIO pio = pio0;
+    int sm = pio_claim_unused_sm(pio, true);
+    uint offset = pio_add_program(pio, &genseq_program);
+    uint gpio = 4;
+    if (argc == 2)
+        gpio = (uint)strtoul(argv[1], NULL, 0);
+    printf("Loaded program at %d, using sm %d, gpio %d\n", offset, sm, gpio);
+
+    pio_sm_config_xfer(pio, sm, PIO_DIR_FROM_SM, 256, 1);
+
+    pio_gpio_init(pio, gpio);
+    pio_sm_set_consecutive_pindirs(pio, sm, gpio, 1, true);
+    pio_sm_config c = genseq_program_get_default_config(offset);
+    sm_config_set_sideset_pins(&c, gpio);
+    pio_sm_init(pio, sm, offset, &c);
+    pio_sm_set_enabled(pio, sm, true);
+
+    for (i = 0; i < DATA_WORDS; i++) {
+        printf("Iter %d:\n", i);
+        pio_sm_put_blocking(pio, sm, i);
+        if (use_dma) {
+            ret = pio_sm_xfer_data(pio, sm, PIO_DIR_FROM_SM, (i + 1) * sizeof(databuf[0]), databuf);
+            if (ret)
+               break;
+
+            for (j = i; j >= 0; j--)
+            {
+                int v = databuf[i - j];
+                if (v != j)
+                    printf(" %d: %d\n", j, v);
+            }
+        } else {
+            for (j = i; j >= 0; j--)
+            {
+                int v = pio_sm_get_blocking(pio, sm);
+                if (v != j)
+                    printf(" %d: %d\n", j, v);
+            }
+        }
+        sleep_ms(10);
+    }
+
+    if (ret)
+        printf("* error %d\n", ret);
+    return ret;
+}

piolib/genseq.pio.h

@@ -0,0 +1,42 @@
+// -------------------------------------------------- //
+// This file is autogenerated by pioasm; do not edit! //
+// -------------------------------------------------- //
+
+#pragma once
+
+#if !PICO_NO_HARDWARE
+#include "hardware/pio.h"
+#endif
+
+// ------ //
+// genseq //
+// ------ //
+
+#define genseq_wrap_target 0
+#define genseq_wrap 4
+
+static const uint16_t genseq_program_instructions[] = {
+            //     .wrap_target
+    0x80a0, //  0: pull   block           side 0     
+    0xa027, //  1: mov    x, osr          side 0     
+    0xa0c1, //  2: mov    isr, x          side 0     
+    0x9020, //  3: push   block           side 1     
+    0x0042, //  4: jmp    x--, 2          side 0     
+            //     .wrap
+};
+
+#if !PICO_NO_HARDWARE
+static const struct pio_program genseq_program = {
+    .instructions = genseq_program_instructions,
+    .length = 5,
+    .origin = -1,
+};
+
+static inline pio_sm_config genseq_program_get_default_config(uint offset) {
+    pio_sm_config c = pio_get_default_sm_config();
+    sm_config_set_wrap(&c, offset + genseq_wrap_target, offset + genseq_wrap);
+    sm_config_set_sideset(&c, 1, false, false);
+    return c;
+}
+#endif
+

piolib/hardware/clocks.h

@@ -0,0 +1,24 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2024 Raspberry Pi Ltd.
+ * All rights reserved.
+ */
+
+#ifndef _HARDWARE_CLOCKS_H
+#define _HARDWARE_CLOCKS_H
+
+enum clock_index {
+    clk_gpout0 = 0,     ///< GPIO Muxing 0
+    clk_gpout1,         ///< GPIO Muxing 1
+    clk_gpout2,         ///< GPIO Muxing 2
+    clk_gpout3,         ///< GPIO Muxing 3
+    clk_ref,            ///< Watchdog and timers reference clock
+    clk_sys,            ///< Processors, bus fabric, memory, memory mapped registers
+    clk_peri,           ///< Peripheral clock for UART and SPI
+    clk_usb,            ///< USB clock
+    clk_adc,            ///< ADC clock
+    clk_rtc,            ///< Real time clock
+    CLK_COUNT
+};
+
+#endif

piolib/hardware/gpio.h

@@ -0,0 +1,63 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2024 Raspberry Pi Ltd.
+ * All rights reserved.
+ */
+#ifndef _HARDWARE_GPIO_H
+#define _HARDWARE_GPIO_H
+
+#include "pio_platform.h"
+
+#ifndef PARAM_ASSERTIONS_ENABLED_GPIO
+#define PARAM_ASSERTIONS_ENABLED_GPIO 0
+#endif
+
+#define NUM_BANK0_GPIOS 32
+
+enum gpio_function {
+    GPIO_FUNC_XIP = 0,
+    GPIO_FUNC_SPI = 1,
+    GPIO_FUNC_UART = 2,
+    GPIO_FUNC_I2C = 3,
+    GPIO_FUNC_PWM = 4,
+    GPIO_FUNC_SIO = 5,
+    GPIO_FUNC_PIO0 = 6,
+    GPIO_FUNC_PIO1 = 7,
+    GPIO_FUNC_GPCK = 8,
+    GPIO_FUNC_USB = 9,
+    GPIO_FUNC_NULL = 0x1f,
+};
+
+#define GPIO_OUT 1
+#define GPIO_IN 0
+
+enum gpio_irq_level {
+    GPIO_IRQ_LEVEL_LOW = 0x1u,
+    GPIO_IRQ_LEVEL_HIGH = 0x2u,
+    GPIO_IRQ_EDGE_FALL = 0x4u,
+    GPIO_IRQ_EDGE_RISE = 0x8u,
+};
+
+enum gpio_override {
+    GPIO_OVERRIDE_NORMAL = 0,      ///< peripheral signal selected via \ref gpio_set_function
+    GPIO_OVERRIDE_INVERT = 1,      ///< invert peripheral signal selected via \ref gpio_set_function
+    GPIO_OVERRIDE_LOW = 2,         ///< drive low/disable output
+    GPIO_OVERRIDE_HIGH = 3,        ///< drive high/enable output
+};
+enum gpio_slew_rate {
+    GPIO_SLEW_RATE_SLOW = 0,  ///< Slew rate limiting enabled
+    GPIO_SLEW_RATE_FAST = 1   ///< Slew rate limiting disabled
+};
+
+enum gpio_drive_strength {
+    GPIO_DRIVE_STRENGTH_2MA = 0, ///< 2 mA nominal drive strength
+    GPIO_DRIVE_STRENGTH_4MA = 1, ///< 4 mA nominal drive strength
+    GPIO_DRIVE_STRENGTH_8MA = 2, ///< 8 mA nominal drive strength
+    GPIO_DRIVE_STRENGTH_12MA = 3 ///< 12 mA nominal drive strength
+};
+
+static inline void check_gpio_param(__unused uint gpio) {
+    invalid_params_if(GPIO, gpio >= NUM_BANK0_GPIOS);
+}
+
+#endif

piolib/hardware/pio.h

@@ -0,0 +1,11 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2024 Raspberry Pi Ltd.
+ * All rights reserved.
+ */
+#ifndef _HARDWARE_PIO_H
+#define _HARDWARE_PIO_H
+
+#include "piolib.h"
+
+#endif