diff options
| 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 /drivers/mtd/devices/mtdram.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 'drivers/mtd/devices/mtdram.c')
| -rw-r--r-- | drivers/mtd/devices/mtdram.c | 187 |
1 files changed, 187 insertions, 0 deletions
diff --git a/drivers/mtd/devices/mtdram.c b/drivers/mtd/devices/mtdram.c new file mode 100644 index 000000000..3fff3cdd9 --- /dev/null +++ b/drivers/mtd/devices/mtdram.c @@ -0,0 +1,187 @@ +/* + * mtdram - a test mtd device + * Author: Alexander Larsson <alex@cendio.se> + * + * Copyright (c) 1999 Alexander Larsson <alex@cendio.se> + * Copyright (c) 2005 Joern Engel <joern@wh.fh-wedel.de> + * + * This code is GPL + * + */ + +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/ioport.h> +#include <linux/vmalloc.h> +#include <linux/mm.h> +#include <linux/init.h> +#include <linux/mtd/mtd.h> +#include <linux/mtd/mtdram.h> + +static unsigned long total_size = CONFIG_MTDRAM_TOTAL_SIZE; +static unsigned long erase_size = CONFIG_MTDRAM_ERASE_SIZE; +static unsigned long writebuf_size = 64; +#define MTDRAM_TOTAL_SIZE (total_size * 1024) +#define MTDRAM_ERASE_SIZE (erase_size * 1024) + +module_param(total_size, ulong, 0); +MODULE_PARM_DESC(total_size, "Total device size in KiB"); +module_param(erase_size, ulong, 0); +MODULE_PARM_DESC(erase_size, "Device erase block size in KiB"); +module_param(writebuf_size, ulong, 0); +MODULE_PARM_DESC(writebuf_size, "Device write buf size in Bytes (Default: 64)"); + +// We could store these in the mtd structure, but we only support 1 device.. +static struct mtd_info *mtd_info; + +static int check_offs_len(struct mtd_info *mtd, loff_t ofs, uint64_t len) +{ + int ret = 0; + + /* Start address must align on block boundary */ + if (mtd_mod_by_eb(ofs, mtd)) { + pr_debug("%s: unaligned address\n", __func__); + ret = -EINVAL; + } + + /* Length must align on block boundary */ + if (mtd_mod_by_eb(len, mtd)) { + pr_debug("%s: length not block aligned\n", __func__); + ret = -EINVAL; + } + + return ret; +} + +static int ram_erase(struct mtd_info *mtd, struct erase_info *instr) +{ + if (check_offs_len(mtd, instr->addr, instr->len)) + return -EINVAL; + memset((char *)mtd->priv + instr->addr, 0xff, instr->len); + + return 0; +} + +static int ram_point(struct mtd_info *mtd, loff_t from, size_t len, + size_t *retlen, void **virt, resource_size_t *phys) +{ + *virt = mtd->priv + from; + *retlen = len; + + if (phys) { + /* limit retlen to the number of contiguous physical pages */ + unsigned long page_ofs = offset_in_page(*virt); + void *addr = *virt - page_ofs; + unsigned long pfn1, pfn0 = vmalloc_to_pfn(addr); + + *phys = __pfn_to_phys(pfn0) + page_ofs; + len += page_ofs; + while (len > PAGE_SIZE) { + len -= PAGE_SIZE; + addr += PAGE_SIZE; + pfn0++; + pfn1 = vmalloc_to_pfn(addr); + if (pfn1 != pfn0) { + *retlen = addr - *virt; + break; + } + } + } + + return 0; +} + +static int ram_unpoint(struct mtd_info *mtd, loff_t from, size_t len) +{ + return 0; +} + +static int ram_read(struct mtd_info *mtd, loff_t from, size_t len, + size_t *retlen, u_char *buf) +{ + memcpy(buf, mtd->priv + from, len); + *retlen = len; + return 0; +} + +static int ram_write(struct mtd_info *mtd, loff_t to, size_t len, + size_t *retlen, const u_char *buf) +{ + memcpy((char *)mtd->priv + to, buf, len); + *retlen = len; + return 0; +} + +static void __exit cleanup_mtdram(void) +{ + if (mtd_info) { + mtd_device_unregister(mtd_info); + vfree(mtd_info->priv); + kfree(mtd_info); + } +} + +int mtdram_init_device(struct mtd_info *mtd, void *mapped_address, + unsigned long size, const char *name) +{ + memset(mtd, 0, sizeof(*mtd)); + + /* Setup the MTD structure */ + mtd->name = name; + mtd->type = MTD_RAM; + mtd->flags = MTD_CAP_RAM; + mtd->size = size; + mtd->writesize = 1; + mtd->writebufsize = writebuf_size; + mtd->erasesize = MTDRAM_ERASE_SIZE; + mtd->priv = mapped_address; + + mtd->owner = THIS_MODULE; + mtd->_erase = ram_erase; + mtd->_point = ram_point; + mtd->_unpoint = ram_unpoint; + mtd->_read = ram_read; + mtd->_write = ram_write; + + if (mtd_device_register(mtd, NULL, 0)) + return -EIO; + + return 0; +} + +static int __init init_mtdram(void) +{ + void *addr; + int err; + + if (!total_size) + return -EINVAL; + + /* Allocate some memory */ + mtd_info = kmalloc_obj(struct mtd_info); + if (!mtd_info) + return -ENOMEM; + + addr = vmalloc(MTDRAM_TOTAL_SIZE); + if (!addr) { + kfree(mtd_info); + mtd_info = NULL; + return -ENOMEM; + } + err = mtdram_init_device(mtd_info, addr, MTDRAM_TOTAL_SIZE, "mtdram test device"); + if (err) { + vfree(addr); + kfree(mtd_info); + mtd_info = NULL; + return err; + } + memset(mtd_info->priv, 0xff, MTDRAM_TOTAL_SIZE); + return err; +} + +module_init(init_mtdram); +module_exit(cleanup_mtdram); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Alexander Larsson <alexl@redhat.com>"); +MODULE_DESCRIPTION("Simulated MTD driver for testing"); |
