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authorNiklas Cassel <cassel@kernel.org>2026-09-16 15:00:32 +0200
committerNiklas Cassel <cassel@kernel.org>2026-09-16 16:18:00 +0200
commit8d836581f9b1f57ceaa2b47654754ef1260b410b (patch)
tree1dbd4d0dfb99c2e238356cbe947e5b0be3e3a571 /arch/m68k/atari/nvram.c
downloadlinux-stable-8d836581f9b1f57ceaa2b47654754ef1260b410b.tar.gz
linux-stable-8d836581f9b1f57ceaa2b47654754ef1260b410b.zip
ata: libata-scsi: fix ata_dsm_trim_pages() kernel-docgrafted
make htmldocs fails with: Documentation/driver-api/libata:604: ./drivers/ata/libata-scsi.c:2301: ERROR: Unexpected indentation. [docutils] The Return: section of ata_dsm_trim_pages() ends its first sentence with a colon and continues with an indented bullet list. reStructuredText requires a blank line before an indented block, so docutils chokes on the list. Simply adding the missing blank line does not work either: Return: is a kernel-doc "special section", which is terminated by the first blank line, so the bullet list would end up in the Description section, detached from the sentence introducing it. Spell the two bounds out as prose instead, so that the Return: section stays self-contained. Documentation-only change. Fixes: e64e6b5dc867 ("ata: libata-scsi: scale DSM TRIM payload by MAX PAGES PER DSM COMMAND") Reported-by: Thomas Huth <thuth@redhat.com> Closes: https://lore.kernel.org/linux-ide/b0a0b8e8-cc4f-4c7b-8bc5-fee0712d405a@redhat.com/ Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Thomas Huth <thuth@redhat.com> Link: https://lore.kernel.org/r/20260916130031.29990-2-cassel@kernel.org Signed-off-by: Niklas Cassel <cassel@kernel.org>
Diffstat (limited to 'arch/m68k/atari/nvram.c')
-rw-r--r--arch/m68k/atari/nvram.c274
1 files changed, 274 insertions, 0 deletions
diff --git a/arch/m68k/atari/nvram.c b/arch/m68k/atari/nvram.c
new file mode 100644
index 000000000..ededc3137
--- /dev/null
+++ b/arch/m68k/atari/nvram.c
@@ -0,0 +1,274 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * CMOS/NV-RAM driver for Atari. Adapted from drivers/char/nvram.c.
+ * Copyright (C) 1997 Roman Hodek <Roman.Hodek@informatik.uni-erlangen.de>
+ * idea by and with help from Richard Jelinek <rj@suse.de>
+ * Portions copyright (c) 2001,2002 Sun Microsystems (thockin@sun.com)
+ * Further contributions from Cesar Barros, Erik Gilling, Tim Hockin and
+ * Wim Van Sebroeck.
+ */
+
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/mc146818rtc.h>
+#include <linux/module.h>
+#include <linux/nvram.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/spinlock.h>
+#include <linux/string_choices.h>
+#include <linux/types.h>
+
+#include <asm/atarihw.h>
+#include <asm/atariints.h>
+
+#define NVRAM_BYTES 50
+
+/* It is worth noting that these functions all access bytes of general
+ * purpose memory in the NVRAM - that is to say, they all add the
+ * NVRAM_FIRST_BYTE offset. Pass them offsets into NVRAM as if you did not
+ * know about the RTC cruft.
+ */
+
+/* Note that *all* calls to CMOS_READ and CMOS_WRITE must be done with
+ * rtc_lock held. Due to the index-port/data-port design of the RTC, we
+ * don't want two different things trying to get to it at once. (e.g. the
+ * periodic 11 min sync from kernel/time/ntp.c vs. this driver.)
+ */
+
+static unsigned char __nvram_read_byte(int i)
+{
+ return CMOS_READ(NVRAM_FIRST_BYTE + i);
+}
+
+/* This races nicely with trying to read with checksum checking */
+static void __nvram_write_byte(unsigned char c, int i)
+{
+ CMOS_WRITE(c, NVRAM_FIRST_BYTE + i);
+}
+
+/* On Ataris, the checksum is over all bytes except the checksum bytes
+ * themselves; these are at the very end.
+ */
+#define ATARI_CKS_RANGE_START 0
+#define ATARI_CKS_RANGE_END 47
+#define ATARI_CKS_LOC 48
+
+static int __nvram_check_checksum(void)
+{
+ int i;
+ unsigned char sum = 0;
+
+ for (i = ATARI_CKS_RANGE_START; i <= ATARI_CKS_RANGE_END; ++i)
+ sum += __nvram_read_byte(i);
+ return (__nvram_read_byte(ATARI_CKS_LOC) == (~sum & 0xff)) &&
+ (__nvram_read_byte(ATARI_CKS_LOC + 1) == (sum & 0xff));
+}
+
+static void __nvram_set_checksum(void)
+{
+ int i;
+ unsigned char sum = 0;
+
+ for (i = ATARI_CKS_RANGE_START; i <= ATARI_CKS_RANGE_END; ++i)
+ sum += __nvram_read_byte(i);
+ __nvram_write_byte(~sum, ATARI_CKS_LOC);
+ __nvram_write_byte(sum, ATARI_CKS_LOC + 1);
+}
+
+long atari_nvram_set_checksum(void)
+{
+ spin_lock_irq(&rtc_lock);
+ __nvram_set_checksum();
+ spin_unlock_irq(&rtc_lock);
+ return 0;
+}
+
+long atari_nvram_initialize(void)
+{
+ loff_t i;
+
+ spin_lock_irq(&rtc_lock);
+ for (i = 0; i < NVRAM_BYTES; ++i)
+ __nvram_write_byte(0, i);
+ __nvram_set_checksum();
+ spin_unlock_irq(&rtc_lock);
+ return 0;
+}
+
+ssize_t atari_nvram_read(char *buf, size_t count, loff_t *ppos)
+{
+ char *p = buf;
+ loff_t i;
+
+ spin_lock_irq(&rtc_lock);
+ if (!__nvram_check_checksum()) {
+ spin_unlock_irq(&rtc_lock);
+ return -EIO;
+ }
+ for (i = *ppos; count > 0 && i < NVRAM_BYTES; --count, ++i, ++p)
+ *p = __nvram_read_byte(i);
+ spin_unlock_irq(&rtc_lock);
+
+ *ppos = i;
+ return p - buf;
+}
+
+ssize_t atari_nvram_write(char *buf, size_t count, loff_t *ppos)
+{
+ char *p = buf;
+ loff_t i;
+
+ spin_lock_irq(&rtc_lock);
+ if (!__nvram_check_checksum()) {
+ spin_unlock_irq(&rtc_lock);
+ return -EIO;
+ }
+ for (i = *ppos; count > 0 && i < NVRAM_BYTES; --count, ++i, ++p)
+ __nvram_write_byte(*p, i);
+ __nvram_set_checksum();
+ spin_unlock_irq(&rtc_lock);
+
+ *ppos = i;
+ return p - buf;
+}
+
+ssize_t atari_nvram_get_size(void)
+{
+ return NVRAM_BYTES;
+}
+
+#ifdef CONFIG_PROC_FS
+static struct {
+ unsigned char val;
+ const char *name;
+} boot_prefs[] = {
+ { 0x80, "TOS" },
+ { 0x40, "ASV" },
+ { 0x20, "NetBSD (?)" },
+ { 0x10, "Linux" },
+ { 0x00, "unspecified" },
+};
+
+static const char * const languages[] = {
+ "English (US)",
+ "German",
+ "French",
+ "English (UK)",
+ "Spanish",
+ "Italian",
+ "6 (undefined)",
+ "Swiss (French)",
+ "Swiss (German)",
+};
+
+static const char * const dateformat[] = {
+ "MM%cDD%cYY",
+ "DD%cMM%cYY",
+ "YY%cMM%cDD",
+ "YY%cDD%cMM",
+ "4 (undefined)",
+ "5 (undefined)",
+ "6 (undefined)",
+ "7 (undefined)",
+};
+
+static const char * const colors[] = {
+ "2", "4", "16", "256", "65536", "??", "??", "??"
+};
+
+static void atari_nvram_proc_read(unsigned char *nvram, struct seq_file *seq,
+ void *offset)
+{
+ int checksum;
+ int i;
+ unsigned int vmode;
+
+ spin_lock_irq(&rtc_lock);
+ checksum = __nvram_check_checksum();
+ spin_unlock_irq(&rtc_lock);
+
+ seq_printf(seq, "Checksum status : %svalid\n", checksum ? "" : "not ");
+
+ seq_puts(seq, "Boot preference : ");
+ for (i = ARRAY_SIZE(boot_prefs) - 1; i >= 0; --i)
+ if (nvram[1] == boot_prefs[i].val) {
+ seq_printf(seq, "%s\n", boot_prefs[i].name);
+ break;
+ }
+ if (i < 0)
+ seq_printf(seq, "0x%02x (undefined)\n", nvram[1]);
+
+ seq_printf(seq, "SCSI arbitration : %s\n",
+ str_on_off(nvram[16] & 0x80));
+ seq_puts(seq, "SCSI host ID : ");
+ if (nvram[16] & 0x80)
+ seq_printf(seq, "%d\n", nvram[16] & 7);
+ else
+ seq_puts(seq, "n/a\n");
+
+ if (!MACH_IS_FALCON)
+ return;
+
+ seq_puts(seq, "OS language : ");
+ if (nvram[6] < ARRAY_SIZE(languages))
+ seq_printf(seq, "%s\n", languages[nvram[6]]);
+ else
+ seq_printf(seq, "%u (undefined)\n", nvram[6]);
+ seq_puts(seq, "Keyboard language: ");
+ if (nvram[7] < ARRAY_SIZE(languages))
+ seq_printf(seq, "%s\n", languages[nvram[7]]);
+ else
+ seq_printf(seq, "%u (undefined)\n", nvram[7]);
+ seq_puts(seq, "Date format : ");
+ seq_printf(seq, dateformat[nvram[8] & 7],
+ nvram[9] ? nvram[9] : '/', nvram[9] ? nvram[9] : '/');
+ seq_printf(seq, ", %dh clock\n", nvram[8] & 16 ? 24 : 12);
+ seq_puts(seq, "Boot delay : ");
+ if (nvram[10] == 0)
+ seq_puts(seq, "default\n");
+ else
+ seq_printf(seq, "%ds%s\n", nvram[10],
+ nvram[10] < 8 ? ", no memory test" : "");
+
+ vmode = (nvram[14] << 8) | nvram[15];
+ seq_printf(seq,
+ "Video mode : %s colors, %d columns, %s %s monitor\n",
+ colors[vmode & 7], vmode & 8 ? 80 : 40,
+ vmode & 16 ? "VGA" : "TV", vmode & 32 ? "PAL" : "NTSC");
+ seq_printf(seq,
+ " %soverscan, compat. mode %s%s\n",
+ vmode & 64 ? "" : "no ", str_on_off(vmode & 128),
+ vmode & 256 ?
+ (vmode & 16 ? ", line doubling" : ", half screen") : "");
+}
+
+static int nvram_proc_read(struct seq_file *seq, void *offset)
+{
+ unsigned char contents[NVRAM_BYTES];
+ int i;
+
+ spin_lock_irq(&rtc_lock);
+ for (i = 0; i < NVRAM_BYTES; ++i)
+ contents[i] = __nvram_read_byte(i);
+ spin_unlock_irq(&rtc_lock);
+
+ atari_nvram_proc_read(contents, seq, offset);
+
+ return 0;
+}
+
+static int __init atari_nvram_init(void)
+{
+ if (!(MACH_IS_ATARI && ATARIHW_PRESENT(TT_CLK)))
+ return -ENODEV;
+
+ if (!proc_create_single("driver/nvram", 0, NULL, nvram_proc_read)) {
+ pr_err("nvram: can't create /proc/driver/nvram\n");
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+device_initcall(atari_nvram_init);
+#endif /* CONFIG_PROC_FS */