From 9cc63f8bcd560c760d0b12e15bba8f81c86237cf Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Fri, 14 Aug 2026 15:43:51 -0700 Subject: Merge branches 'expcb.2026.07.24a', 'misc.2026.07.30a', 'rcu-tasks.2026.07.30a', 'srcu.2026.08.11a' and 'torture.2026.08.14a' into HEAD Changes: Make expedited grace periods expedite normal RCU callbacks Miscellaneous fixes: * Improve diagnostic output with character task states. * Mark accesses to inform KCSAN of concurrency design. * Move from kmalloc() to kmalloc_obj(). * Documentation updates. * Improve handling of RCU deferred quiescent states. * Clean up unused function arguments and structure fields. * Reduce show_rcu_gp_kthreads() stack space. Tasks RCU updates: * Clean up after SRCU re-implementation of Tasks Trace RCU. * Mark accesses to inform KCSAN of concurrency design. * Add ->lazy_timer status to diagnostic output. * Remove an unnecessary memory barrier. * Fix a data race, courtesy of KCSAN. * Documentation updates. * Convert cond_resched_tasks_rcu_qs() from macro to static inline function. SRCU updates: * Add Rust helpers for SRCU. * Avoid losing queued work at cleanup_srcu_struct() time. Torture-test updates: * Preparation work for immediate RCU priority deboosting. * Test RCU readers from real interrupt handlers (as opposed to softirq). * Simplify code through use of cpumask_next_wrap(). * Improve diagnostic output with character task states. * Add rcutorture.nwriters parameter to allow lightweight stall testing, and rcutorture.stall_only to make doing so easier. * Test an RCU Tasks Trace grace period implying an RCU grace period. * Make RCU Tasks Trace torturing track reader batches. * Fix a data race, courtesy of KCSAN. * Plug a shuffle_tmp_mask memory leak on kthread spawn failure. --- samples/auxdisplay/.gitignore | 2 + samples/auxdisplay/Makefile | 2 + samples/auxdisplay/cfag12864b-example.c | 267 ++++++++++++++++++++++++++++++++ 3 files changed, 271 insertions(+) create mode 100644 samples/auxdisplay/.gitignore create mode 100644 samples/auxdisplay/Makefile create mode 100644 samples/auxdisplay/cfag12864b-example.c (limited to 'samples/auxdisplay') diff --git a/samples/auxdisplay/.gitignore b/samples/auxdisplay/.gitignore new file mode 100644 index 000000000..d02381684 --- /dev/null +++ b/samples/auxdisplay/.gitignore @@ -0,0 +1,2 @@ +# SPDX-License-Identifier: GPL-2.0-only +/cfag12864b-example diff --git a/samples/auxdisplay/Makefile b/samples/auxdisplay/Makefile new file mode 100644 index 000000000..19d556893 --- /dev/null +++ b/samples/auxdisplay/Makefile @@ -0,0 +1,2 @@ +# SPDX-License-Identifier: GPL-2.0 +userprogs-always-y += cfag12864b-example diff --git a/samples/auxdisplay/cfag12864b-example.c b/samples/auxdisplay/cfag12864b-example.c new file mode 100644 index 000000000..2e3bb7375 --- /dev/null +++ b/samples/auxdisplay/cfag12864b-example.c @@ -0,0 +1,267 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Filename: cfag12864b-example.c + * Version: 0.1.0 + * Description: cfag12864b LCD userspace example program + * + * Author: Copyright (C) Miguel Ojeda + * Date: 2006-10-31 + */ + +/* + * ------------------------ + * start of cfag12864b code + * ------------------------ + */ + +#include +#include +#include +#include +#include +#include + +#define CFAG12864B_WIDTH (128) +#define CFAG12864B_HEIGHT (64) +#define CFAG12864B_SIZE (128 * 64 / 8) +#define CFAG12864B_BPB (8) +#define CFAG12864B_ADDRESS(x, y) ((y) * CFAG12864B_WIDTH / \ + CFAG12864B_BPB + (x) / CFAG12864B_BPB) +#define CFAG12864B_BIT(n) (((unsigned char) 1) << (n)) + +#undef CFAG12864B_DOCHECK +#ifdef CFAG12864B_DOCHECK + #define CFAG12864B_CHECK(x, y) ((x) < CFAG12864B_WIDTH && \ + (y) < CFAG12864B_HEIGHT) +#else + #define CFAG12864B_CHECK(x, y) (1) +#endif + +int cfag12864b_fd; +unsigned char * cfag12864b_mem; +unsigned char cfag12864b_buffer[CFAG12864B_SIZE]; + +/* + * init a cfag12864b framebuffer device + * + * No error: return = 0 + * Unable to open: return = -1 + * Unable to mmap: return = -2 + */ +static int cfag12864b_init(char *path) +{ + cfag12864b_fd = open(path, O_RDWR); + if (cfag12864b_fd == -1) + return -1; + + cfag12864b_mem = mmap(0, CFAG12864B_SIZE, PROT_READ | PROT_WRITE, + MAP_SHARED, cfag12864b_fd, 0); + if (cfag12864b_mem == MAP_FAILED) { + close(cfag12864b_fd); + return -2; + } + + return 0; +} + +/* + * exit a cfag12864b framebuffer device + */ +static void cfag12864b_exit(void) +{ + munmap(cfag12864b_mem, CFAG12864B_SIZE); + close(cfag12864b_fd); +} + +/* + * set (x, y) pixel + */ +static void cfag12864b_set(unsigned char x, unsigned char y) +{ + if (CFAG12864B_CHECK(x, y)) + cfag12864b_buffer[CFAG12864B_ADDRESS(x, y)] |= + CFAG12864B_BIT(x % CFAG12864B_BPB); +} + +/* + * unset (x, y) pixel + */ +static void cfag12864b_unset(unsigned char x, unsigned char y) +{ + if (CFAG12864B_CHECK(x, y)) + cfag12864b_buffer[CFAG12864B_ADDRESS(x, y)] &= + ~CFAG12864B_BIT(x % CFAG12864B_BPB); +} + +/* + * is set (x, y) pixel? + * + * Pixel off: return = 0 + * Pixel on: return = 1 + */ +static unsigned char cfag12864b_isset(unsigned char x, unsigned char y) +{ + if (CFAG12864B_CHECK(x, y)) + if (cfag12864b_buffer[CFAG12864B_ADDRESS(x, y)] & + CFAG12864B_BIT(x % CFAG12864B_BPB)) + return 1; + + return 0; +} + +/* + * not (x, y) pixel + */ +static void cfag12864b_not(unsigned char x, unsigned char y) +{ + if (cfag12864b_isset(x, y)) + cfag12864b_unset(x, y); + else + cfag12864b_set(x, y); +} + +/* + * fill (set all pixels) + */ +static void cfag12864b_fill(void) +{ + unsigned short i; + + for (i = 0; i < CFAG12864B_SIZE; i++) + cfag12864b_buffer[i] = 0xFF; +} + +/* + * clear (unset all pixels) + */ +static void cfag12864b_clear(void) +{ + unsigned short i; + + for (i = 0; i < CFAG12864B_SIZE; i++) + cfag12864b_buffer[i] = 0; +} + +/* + * format a [128*64] matrix + * + * Pixel off: src[i] = 0 + * Pixel on: src[i] > 0 + */ +static void cfag12864b_format(unsigned char * matrix) +{ + unsigned char i, j, n; + + for (i = 0; i < CFAG12864B_HEIGHT; i++) + for (j = 0; j < CFAG12864B_WIDTH / CFAG12864B_BPB; j++) { + cfag12864b_buffer[i * CFAG12864B_WIDTH / CFAG12864B_BPB + + j] = 0; + for (n = 0; n < CFAG12864B_BPB; n++) + if (matrix[i * CFAG12864B_WIDTH + + j * CFAG12864B_BPB + n]) + cfag12864b_buffer[i * CFAG12864B_WIDTH / + CFAG12864B_BPB + j] |= + CFAG12864B_BIT(n); + } +} + +/* + * blit buffer to lcd + */ +static void cfag12864b_blit(void) +{ + memcpy(cfag12864b_mem, cfag12864b_buffer, CFAG12864B_SIZE); +} + +/* + * ---------------------- + * end of cfag12864b code + * ---------------------- + */ + +#include + +#define EXAMPLES 6 + +static void example(unsigned char n) +{ + unsigned short i, j; + unsigned char matrix[CFAG12864B_WIDTH * CFAG12864B_HEIGHT]; + + if (n > EXAMPLES) + return; + + printf("Example %i/%i - ", n, EXAMPLES); + + switch (n) { + case 1: + printf("Draw points setting bits"); + cfag12864b_clear(); + for (i = 0; i < CFAG12864B_WIDTH; i += 2) + for (j = 0; j < CFAG12864B_HEIGHT; j += 2) + cfag12864b_set(i, j); + break; + + case 2: + printf("Clear the LCD"); + cfag12864b_clear(); + break; + + case 3: + printf("Draw rows formatting a [128*64] matrix"); + memset(matrix, 0, CFAG12864B_WIDTH * CFAG12864B_HEIGHT); + for (i = 0; i < CFAG12864B_WIDTH; i++) + for (j = 0; j < CFAG12864B_HEIGHT; j += 2) + matrix[j * CFAG12864B_WIDTH + i] = 1; + cfag12864b_format(matrix); + break; + + case 4: + printf("Fill the lcd"); + cfag12864b_fill(); + break; + + case 5: + printf("Draw columns unsetting bits"); + for (i = 0; i < CFAG12864B_WIDTH; i += 2) + for (j = 0; j < CFAG12864B_HEIGHT; j++) + cfag12864b_unset(i, j); + break; + + case 6: + printf("Do negative not-ing all bits"); + for (i = 0; i < CFAG12864B_WIDTH; i++) + for (j = 0; j < CFAG12864B_HEIGHT; j ++) + cfag12864b_not(i, j); + break; + } + + puts(" - [Press Enter]"); +} + +int main(int argc, char *argv[]) +{ + unsigned char n; + + if (argc != 2) { + printf( + "Syntax: %s fbdev\n" + "Usually: /dev/fb0, /dev/fb1...\n", argv[0]); + return -1; + } + + if (cfag12864b_init(argv[1])) { + printf("Can't init %s fbdev\n", argv[1]); + return -2; + } + + for (n = 1; n <= EXAMPLES; n++) { + example(n); + cfag12864b_blit(); + while (getchar() != '\n'); + } + + cfag12864b_exit(); + + return 0; +} -- cgit v1.3.1