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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-30 09:22:00 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-30 09:22:00 -0700
commit034dd340b08be1f2f0477ad16131d609f9dbd53c (patch)
tree2536f4b2d7893ccd916b5abdf3c454ad6edc03c2 /drivers/video/fbdev/grvga.c
downloadlinux-stable-034dd340b08be1f2f0477ad16131d609f9dbd53c.tar.gz
linux-stable-034dd340b08be1f2f0477ad16131d609f9dbd53c.zip
Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted
Pull tracing fixes from Steven Rostedt: - Fix error output of boot instance creation failure Currently if a boot instance creation fails, instead of printing out the name of the instance that failed, it prints "(null)". That is because it prints "cur_str" that had already been processed by strsep(). Print the saved name instead. While at it, print the error code of the failure. - Fix use-after-free for same named historgrams Histograms can be named so that they can be used in multiple events. But if the named histogram has a variable attached, the second event that uses the named histogram which duplicates it and needs to free the original after duplication leaves the old variable in place and still visible. If another histogram uses than variable, it will use the stale one which will try to reference the freed duplicate histogram and crash the kernel. Free the duplicate variables along with the duplicated histogram data. - Check return value of kthread_run() in event self test The events self tests uses a kthread for testing but does not check if it succeeded in creating a kthread. If the kthread creation were to fail, the code will still try to call kthread_stop() on the error returned. - Fix race between reading trace_pipe and updating subbuffer size If a user is reading the trace_pipe file at the same time they update the ring buffer sub-buffer size, can cause the trace_pipe read to read stale data. Add trace_access_lock() around updating the ring buffer sub-buffer size. - Fix eventfs_inode on failure path in creation of the events directory In the creation of the "events" directory, if after allocating the eventfs_inode a failure is detected, it calls cleanup_ei() which calls free_ei(). The free_ei() will test if eventfs_inode being freed has no children. It is a bug if it does. But on the failure case of the creation of the "events" directory, the children lists have not yet been initialized and the free will trigger a warning because list_empty() on an uninitialized list returns false. Move the initialization into init_ei() where it makes more sense and makes sure that a created eventfs_inode has its lists initialized upon creation. - Check return value of kthread_run() in ftrace direct sample code The sample code that shows how to use the ftrace direct calls does not test the return of kthread_run() to see if it succeeds. Return a failure if the kthread_run() doesn't succeed. - Clear user events state on fork in case of alloc failure On fork, the child gets a pointer to the parent's user events state. It makes a copy of it then updates the child's pointer to it. But if the allocation fails, the duplication function leaves the child with a pointer to its parent's descriptor. When the child cleans up its data, it will free the parent's descriptor while the parent is still using it. In the duplication function, set the child's user_event_mm to NULL before testing if the allocation succeeded, and when it exits it will not free the parent's descriptor. - Fix retry exhaustion in simple ring buffer reader swap simple_ring_buffer_swap_reader_page() starts with retry set to 8 and post-decrements it only after a failed link replacement. On the final attempt, a successful replacement leaves retry at zero, while a failed replacement leaves it at -1. But the check for success expects the retry value to be non-zero and exits with an error on zero. This is the opposite result. Fix it. - Fail nicely when the remote swap_reader_page() returns an error Currently, if the swap_reader_page() of a remote buffer fails, it triggers a WARN_ON_ONCE() and continues normally. Instead, have it exit with an error and a pr_warn() print instead of a full WARNING. * tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: ring-buffer: Stop remote reader update when page swap fails tracing: Fix retry exhaustion in simple ring buffer reader swap tracing/user_events: Clear copied tracing state before fork duplication samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify eventfs: Initialize ei->children and ei->list in init_ei() tracing: Fix use-after-free in trace_pipe read on sub-buffer order change tracing: Fix crash passing ERR_PTR to kthread_stop() tracing: Fix use-after-free with same-name named triggers tracing: Fix logged instance name on creation failure
Diffstat (limited to 'drivers/video/fbdev/grvga.c')
-rw-r--r--drivers/video/fbdev/grvga.c550
1 files changed, 550 insertions, 0 deletions
diff --git a/drivers/video/fbdev/grvga.c b/drivers/video/fbdev/grvga.c
new file mode 100644
index 000000000..a6594bcd7
--- /dev/null
+++ b/drivers/video/fbdev/grvga.c
@@ -0,0 +1,550 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Driver for Aeroflex Gaisler SVGACTRL framebuffer device.
+ *
+ * 2011 (c) Aeroflex Gaisler AB
+ *
+ * Full documentation of the core can be found here:
+ * https://www.gaisler.com/products/grlib/grip.pdf
+ *
+ * Contributors: Kristoffer Glembo <kristoffer@gaisler.com>
+ */
+
+#include <linux/platform_device.h>
+#include <linux/dma-mapping.h>
+#include <linux/of.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/delay.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/tty.h>
+#include <linux/mm.h>
+#include <linux/fb.h>
+#include <linux/io.h>
+
+struct grvga_regs {
+ u32 status; /* 0x00 */
+ u32 video_length; /* 0x04 */
+ u32 front_porch; /* 0x08 */
+ u32 sync_length; /* 0x0C */
+ u32 line_length; /* 0x10 */
+ u32 fb_pos; /* 0x14 */
+ u32 clk_vector[4]; /* 0x18 */
+ u32 clut; /* 0x28 */
+};
+
+struct grvga_par {
+ struct grvga_regs *regs;
+ u32 color_palette[16]; /* 16 entry pseudo palette used by fbcon in true color mode */
+ int clk_sel;
+ int fb_alloced; /* = 1 if framebuffer is allocated in main memory */
+};
+
+
+static const struct fb_videomode grvga_modedb[] = {
+ {
+ /* 640x480 @ 60 Hz */
+ NULL, 60, 640, 480, 40000, 48, 16, 39, 11, 96, 2,
+ 0, FB_VMODE_NONINTERLACED
+ }, {
+ /* 800x600 @ 60 Hz */
+ NULL, 60, 800, 600, 25000, 88, 40, 23, 1, 128, 4,
+ 0, FB_VMODE_NONINTERLACED
+ }, {
+ /* 800x600 @ 72 Hz */
+ NULL, 72, 800, 600, 20000, 64, 56, 23, 37, 120, 6,
+ 0, FB_VMODE_NONINTERLACED
+ }, {
+ /* 1024x768 @ 60 Hz */
+ NULL, 60, 1024, 768, 15385, 160, 24, 29, 3, 136, 6,
+ 0, FB_VMODE_NONINTERLACED
+ }
+ };
+
+static const struct fb_fix_screeninfo grvga_fix = {
+ .id = "AG SVGACTRL",
+ .type = FB_TYPE_PACKED_PIXELS,
+ .visual = FB_VISUAL_PSEUDOCOLOR,
+ .xpanstep = 0,
+ .ypanstep = 1,
+ .ywrapstep = 0,
+ .accel = FB_ACCEL_NONE,
+};
+
+static int grvga_check_var(struct fb_var_screeninfo *var,
+ struct fb_info *info)
+{
+ struct grvga_par *par = info->par;
+ int i;
+
+ if (!var->xres)
+ var->xres = 1;
+ if (!var->yres)
+ var->yres = 1;
+ if (var->bits_per_pixel <= 8)
+ var->bits_per_pixel = 8;
+ else if (var->bits_per_pixel <= 16)
+ var->bits_per_pixel = 16;
+ else if (var->bits_per_pixel <= 24)
+ var->bits_per_pixel = 24;
+ else if (var->bits_per_pixel <= 32)
+ var->bits_per_pixel = 32;
+ else
+ return -EINVAL;
+
+ var->xres_virtual = var->xres;
+ var->yres_virtual = 2*var->yres;
+
+ if (info->fix.smem_len) {
+ if ((var->yres_virtual*var->xres_virtual*var->bits_per_pixel/8) > info->fix.smem_len)
+ return -ENOMEM;
+ }
+
+ /* Which clocks that are available can be read out in these registers */
+ for (i = 0; i <= 3 ; i++) {
+ if (var->pixclock == par->regs->clk_vector[i])
+ break;
+ }
+ if (i <= 3)
+ par->clk_sel = i;
+ else
+ return -EINVAL;
+
+ switch (info->var.bits_per_pixel) {
+ case 8:
+ var->red = (struct fb_bitfield) {0, 8, 0}; /* offset, length, msb-right */
+ var->green = (struct fb_bitfield) {0, 8, 0};
+ var->blue = (struct fb_bitfield) {0, 8, 0};
+ var->transp = (struct fb_bitfield) {0, 0, 0};
+ break;
+ case 16:
+ var->red = (struct fb_bitfield) {11, 5, 0};
+ var->green = (struct fb_bitfield) {5, 6, 0};
+ var->blue = (struct fb_bitfield) {0, 5, 0};
+ var->transp = (struct fb_bitfield) {0, 0, 0};
+ break;
+ case 24:
+ case 32:
+ var->red = (struct fb_bitfield) {16, 8, 0};
+ var->green = (struct fb_bitfield) {8, 8, 0};
+ var->blue = (struct fb_bitfield) {0, 8, 0};
+ var->transp = (struct fb_bitfield) {24, 8, 0};
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int grvga_set_par(struct fb_info *info)
+{
+
+ u32 func = 0;
+ struct grvga_par *par = info->par;
+
+ __raw_writel(((info->var.yres - 1) << 16) | (info->var.xres - 1),
+ &par->regs->video_length);
+
+ __raw_writel((info->var.lower_margin << 16) | (info->var.right_margin),
+ &par->regs->front_porch);
+
+ __raw_writel((info->var.vsync_len << 16) | (info->var.hsync_len),
+ &par->regs->sync_length);
+
+ __raw_writel(((info->var.yres + info->var.lower_margin + info->var.upper_margin + info->var.vsync_len - 1) << 16) |
+ (info->var.xres + info->var.right_margin + info->var.left_margin + info->var.hsync_len - 1),
+ &par->regs->line_length);
+
+ switch (info->var.bits_per_pixel) {
+ case 8:
+ info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
+ func = 1;
+ break;
+ case 16:
+ info->fix.visual = FB_VISUAL_TRUECOLOR;
+ func = 2;
+ break;
+ case 24:
+ case 32:
+ info->fix.visual = FB_VISUAL_TRUECOLOR;
+ func = 3;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ __raw_writel((par->clk_sel << 6) | (func << 4) | 1,
+ &par->regs->status);
+
+ info->fix.line_length = (info->var.xres_virtual*info->var.bits_per_pixel)/8;
+ return 0;
+}
+
+static int grvga_setcolreg(unsigned regno, unsigned red, unsigned green, unsigned blue, unsigned transp, struct fb_info *info)
+{
+ struct grvga_par *par;
+ par = info->par;
+
+ if (regno >= 256) /* Size of CLUT */
+ return -EINVAL;
+
+ if (info->var.grayscale) {
+ /* grayscale = 0.30*R + 0.59*G + 0.11*B */
+ red = green = blue = (red * 77 + green * 151 + blue * 28) >> 8;
+ }
+
+
+
+#define CNVT_TOHW(val, width) ((((val)<<(width))+0x7FFF-(val))>>16)
+
+ red = CNVT_TOHW(red, info->var.red.length);
+ green = CNVT_TOHW(green, info->var.green.length);
+ blue = CNVT_TOHW(blue, info->var.blue.length);
+ transp = CNVT_TOHW(transp, info->var.transp.length);
+
+#undef CNVT_TOHW
+
+ /* In PSEUDOCOLOR we use the hardware CLUT */
+ if (info->fix.visual == FB_VISUAL_PSEUDOCOLOR)
+ __raw_writel((regno << 24) | (red << 16) | (green << 8) | blue,
+ &par->regs->clut);
+
+ /* Truecolor uses the pseudo palette */
+ else if (info->fix.visual == FB_VISUAL_TRUECOLOR) {
+ u32 v;
+ if (regno >= 16)
+ return -EINVAL;
+
+
+ v = (red << info->var.red.offset) |
+ (green << info->var.green.offset) |
+ (blue << info->var.blue.offset) |
+ (transp << info->var.transp.offset);
+
+ ((u32 *) (info->pseudo_palette))[regno] = v;
+ }
+ return 0;
+}
+
+static int grvga_pan_display(struct fb_var_screeninfo *var,
+ struct fb_info *info)
+{
+ struct grvga_par *par = info->par;
+ struct fb_fix_screeninfo *fix = &info->fix;
+ u32 base_addr;
+
+ if (var->xoffset != 0)
+ return -EINVAL;
+
+ base_addr = fix->smem_start + (var->yoffset * fix->line_length);
+ base_addr &= ~3UL;
+
+ /* Set framebuffer base address */
+ __raw_writel(base_addr,
+ &par->regs->fb_pos);
+
+ return 0;
+}
+
+static const struct fb_ops grvga_ops = {
+ .owner = THIS_MODULE,
+ FB_DEFAULT_IOMEM_OPS,
+ .fb_check_var = grvga_check_var,
+ .fb_set_par = grvga_set_par,
+ .fb_setcolreg = grvga_setcolreg,
+ .fb_pan_display = grvga_pan_display,
+};
+
+static int grvga_parse_custom(char *options,
+ struct fb_var_screeninfo *screendata)
+{
+ char *this_opt;
+ int count = 0;
+ if (!options || !*options)
+ return -1;
+
+ while ((this_opt = strsep(&options, " ")) != NULL) {
+ if (!*this_opt)
+ continue;
+
+ switch (count) {
+ case 0:
+ screendata->pixclock = simple_strtoul(this_opt, NULL, 0);
+ count++;
+ break;
+ case 1:
+ screendata->xres = screendata->xres_virtual = simple_strtoul(this_opt, NULL, 0);
+ count++;
+ break;
+ case 2:
+ screendata->right_margin = simple_strtoul(this_opt, NULL, 0);
+ count++;
+ break;
+ case 3:
+ screendata->hsync_len = simple_strtoul(this_opt, NULL, 0);
+ count++;
+ break;
+ case 4:
+ screendata->left_margin = simple_strtoul(this_opt, NULL, 0);
+ count++;
+ break;
+ case 5:
+ screendata->yres = screendata->yres_virtual = simple_strtoul(this_opt, NULL, 0);
+ count++;
+ break;
+ case 6:
+ screendata->lower_margin = simple_strtoul(this_opt, NULL, 0);
+ count++;
+ break;
+ case 7:
+ screendata->vsync_len = simple_strtoul(this_opt, NULL, 0);
+ count++;
+ break;
+ case 8:
+ screendata->upper_margin = simple_strtoul(this_opt, NULL, 0);
+ count++;
+ break;
+ case 9:
+ screendata->bits_per_pixel = simple_strtoul(this_opt, NULL, 0);
+ count++;
+ break;
+ default:
+ return -1;
+ }
+ }
+ screendata->activate = FB_ACTIVATE_NOW;
+ screendata->vmode = FB_VMODE_NONINTERLACED;
+ return 0;
+}
+
+static int grvga_probe(struct platform_device *dev)
+{
+ struct fb_info *info;
+ int retval = -ENOMEM;
+ unsigned long virtual_start;
+ unsigned long grvga_fix_addr = 0;
+ unsigned long physical_start = 0;
+ unsigned long grvga_mem_size = 0;
+ struct grvga_par *par = NULL;
+ char *options = NULL, *mode_opt = NULL;
+
+ info = framebuffer_alloc(sizeof(struct grvga_par), &dev->dev);
+ if (!info)
+ return -ENOMEM;
+
+ /* Expecting: "grvga: modestring, [addr:<framebuffer physical address>], [size:<framebuffer size>]
+ *
+ * If modestring is custom:<custom mode string> we parse the string which then contains all videoparameters
+ * If address is left out, we allocate memory,
+ * if size is left out we only allocate enough to support the given mode.
+ */
+ if (fb_get_options("grvga", &options)) {
+ retval = -ENODEV;
+ goto free_fb;
+ }
+
+ if (!options || !*options)
+ options = "640x480-8@60";
+
+ while (1) {
+ char *this_opt = strsep(&options, ",");
+
+ if (!this_opt)
+ break;
+
+ if (!strncmp(this_opt, "custom", 6)) {
+ if (grvga_parse_custom(this_opt, &info->var) < 0) {
+ dev_err(&dev->dev, "Failed to parse custom mode (%s).\n", this_opt);
+ retval = -EINVAL;
+ goto free_fb;
+ }
+ } else if (!strncmp(this_opt, "addr", 4))
+ grvga_fix_addr = simple_strtoul(this_opt + 5, NULL, 16);
+ else if (!strncmp(this_opt, "size", 4))
+ grvga_mem_size = simple_strtoul(this_opt + 5, NULL, 0);
+ else
+ mode_opt = this_opt;
+ }
+
+ par = info->par;
+ info->fbops = &grvga_ops;
+ info->fix = grvga_fix;
+ info->pseudo_palette = par->color_palette;
+ info->flags = FBINFO_PARTIAL_PAN_OK | FBINFO_HWACCEL_YPAN;
+ info->fix.smem_len = grvga_mem_size;
+
+ if (!devm_request_mem_region(&dev->dev, dev->resource[0].start,
+ resource_size(&dev->resource[0]), "grlib-svgactrl regs")) {
+ dev_err(&dev->dev, "registers already mapped\n");
+ retval = -EBUSY;
+ goto free_fb;
+ }
+
+ par->regs = of_ioremap(&dev->resource[0], 0,
+ resource_size(&dev->resource[0]),
+ "grlib-svgactrl regs");
+
+ if (!par->regs) {
+ dev_err(&dev->dev, "failed to map registers\n");
+ retval = -ENOMEM;
+ goto free_fb;
+ }
+
+ retval = fb_alloc_cmap(&info->cmap, 256, 0);
+ if (retval < 0) {
+ dev_err(&dev->dev, "failed to allocate mem with fb_alloc_cmap\n");
+ retval = -ENOMEM;
+ goto unmap_regs;
+ }
+
+ if (mode_opt) {
+ retval = fb_find_mode(&info->var, info, mode_opt,
+ grvga_modedb, sizeof(grvga_modedb), &grvga_modedb[0], 8);
+ if (!retval || retval == 4) {
+ retval = -EINVAL;
+ goto dealloc_cmap;
+ }
+ }
+
+ if (!grvga_mem_size)
+ grvga_mem_size = info->var.xres_virtual * info->var.yres_virtual * info->var.bits_per_pixel/8;
+
+ if (grvga_fix_addr) {
+ /* Got framebuffer base address from argument list */
+
+ physical_start = grvga_fix_addr;
+
+ if (!devm_request_mem_region(&dev->dev, physical_start,
+ grvga_mem_size, dev->name)) {
+ dev_err(&dev->dev, "failed to request memory region\n");
+ retval = -ENOMEM;
+ goto dealloc_cmap;
+ }
+
+ virtual_start = (unsigned long) ioremap(physical_start, grvga_mem_size);
+
+ if (!virtual_start) {
+ dev_err(&dev->dev, "error mapping framebuffer memory\n");
+ retval = -ENOMEM;
+ goto dealloc_cmap;
+ }
+ } else { /* Allocate frambuffer memory */
+
+ unsigned long page;
+
+ virtual_start = (unsigned long) __get_free_pages(GFP_DMA,
+ get_order(grvga_mem_size));
+ if (!virtual_start) {
+ dev_err(&dev->dev,
+ "unable to allocate framebuffer memory (%lu bytes)\n",
+ grvga_mem_size);
+ retval = -ENOMEM;
+ goto dealloc_cmap;
+ }
+
+ physical_start = dma_map_single(&dev->dev, (void *)virtual_start, grvga_mem_size, DMA_TO_DEVICE);
+
+ /* Set page reserved so that mmap will work. This is necessary
+ * since we'll be remapping normal memory.
+ */
+ for (page = virtual_start;
+ page < PAGE_ALIGN(virtual_start + grvga_mem_size);
+ page += PAGE_SIZE) {
+ SetPageReserved(virt_to_page(page));
+ }
+
+ par->fb_alloced = 1;
+ }
+
+ memset((unsigned long *) virtual_start, 0, grvga_mem_size);
+
+ info->screen_base = (char __iomem *) virtual_start;
+ info->fix.smem_start = physical_start;
+ info->fix.smem_len = grvga_mem_size;
+
+ dev_set_drvdata(&dev->dev, info);
+
+ dev_info(&dev->dev,
+ "Aeroflex Gaisler framebuffer device (fb%d), %dx%d-%d, using %luK of video memory @ %p\n",
+ info->node, info->var.xres, info->var.yres, info->var.bits_per_pixel,
+ grvga_mem_size >> 10, info->screen_base);
+
+ retval = register_framebuffer(info);
+ if (retval < 0) {
+ dev_err(&dev->dev, "failed to register framebuffer\n");
+ goto free_mem;
+ }
+
+ __raw_writel(physical_start, &par->regs->fb_pos);
+ __raw_writel(__raw_readl(&par->regs->status) | 1, /* Enable framebuffer */
+ &par->regs->status);
+
+ return 0;
+
+free_mem:
+ if (grvga_fix_addr)
+ iounmap((void *)virtual_start);
+ else
+ kfree((void *)virtual_start);
+dealloc_cmap:
+ fb_dealloc_cmap(&info->cmap);
+unmap_regs:
+ of_iounmap(&dev->resource[0], par->regs,
+ resource_size(&dev->resource[0]));
+free_fb:
+ framebuffer_release(info);
+
+ return retval;
+}
+
+static void grvga_remove(struct platform_device *device)
+{
+ struct fb_info *info = dev_get_drvdata(&device->dev);
+ struct grvga_par *par;
+
+ if (info) {
+ par = info->par;
+ unregister_framebuffer(info);
+ fb_dealloc_cmap(&info->cmap);
+
+ of_iounmap(&device->resource[0], par->regs,
+ resource_size(&device->resource[0]));
+
+ if (!par->fb_alloced)
+ iounmap(info->screen_base);
+ else
+ kfree((void *)info->screen_base);
+
+ framebuffer_release(info);
+ }
+}
+
+static struct of_device_id svgactrl_of_match[] = {
+ {
+ .name = "GAISLER_SVGACTRL",
+ },
+ {
+ .name = "01_063",
+ },
+ {},
+};
+MODULE_DEVICE_TABLE(of, svgactrl_of_match);
+
+static struct platform_driver grvga_driver = {
+ .driver = {
+ .name = "grlib-svgactrl",
+ .of_match_table = svgactrl_of_match,
+ },
+ .probe = grvga_probe,
+ .remove = grvga_remove,
+};
+
+module_platform_driver(grvga_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Aeroflex Gaisler");
+MODULE_DESCRIPTION("Aeroflex Gaisler framebuffer device driver");