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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-23 13:28:57 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-23 13:28:57 -0700 |
| commit | 4352b8aee98005853aa63f57d6377282de17a33f (patch) | |
| tree | 27614d7a9ef05c32d089004e104364ce42324837 /arch/m68k/atari/nvram.c | |
| download | linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip | |
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni:
"A new driver this cycle, for the AMD AXI I3C controller.
There are also new features such as IBI wakeup support, SETAASA device
discovery and ACPI support for the the DAA methods, meaning we can now
communicate with the SPD devices on DDR5 modules.
New driver:
- AMD AXI I3C master controller
Subsystem:
- I3C Common Command Code (CCC) handling improvements, especially
around GET CCCs
- SETAASA device discovery support
- ACPI support for all existing DAA methods like SETDASA, SETNEWDA as
well as I2C devices on I3C bus
- IBI-based wakeup support
Drivers:
- dw: SETAASA support
- mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C
controller support, PIO queue management support for HCI v1.2
- renesas: improve suspend to RAM support, add runtime PM support"
* tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits)
i3c: dw: reduce do_daa time if there's no client
i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller
i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2
i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode
i3c: dw: rename "pclk" to "apb" to match dt-binding
i3c: dw: make struct dw_i3c_cmd smaller
i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding
i3c: renesas: Don't register devices when ENTDAA times out
i3c: master: dw-i3c-master: fix OD timing for first broadcast
i3c: mipi-i3c-hci: Advertise IBI wakeup capability
i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev()
i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI
i3c: master: Reject IBI requests from non-IBI-capable devices
i3c: master: Add helper to query bus wakeup requirements
i3c: master: Report wakeup events for IBIs
i3c: master: Support IBI-based wakeup capability
i3c: master: Fix potential UAF in i3c_device_match()
i3c: master: Fix potential UAF in i3c_device_uevent()
i3c: Make dev->desc locking assumptions explicit
i3c: master: Fix use-after-free of master->this
...
Diffstat (limited to 'arch/m68k/atari/nvram.c')
| -rw-r--r-- | arch/m68k/atari/nvram.c | 274 |
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 */ |
