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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 /drivers/misc/altera-stapl/altera-comp.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/misc/altera-stapl/altera-comp.c')
| -rw-r--r-- | drivers/misc/altera-stapl/altera-comp.c | 128 |
1 files changed, 128 insertions, 0 deletions
diff --git a/drivers/misc/altera-stapl/altera-comp.c b/drivers/misc/altera-stapl/altera-comp.c new file mode 100644 index 000000000..4a63f51cc --- /dev/null +++ b/drivers/misc/altera-stapl/altera-comp.c @@ -0,0 +1,128 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * altera-comp.c + * + * altera FPGA driver + * + * Copyright (C) Altera Corporation 1998-2001 + * Copyright (C) 2010 NetUP Inc. + * Copyright (C) 2010 Igor M. Liplianin <liplianin@netup.ru> + */ + +#include <linux/kernel.h> +#include "altera-exprt.h" + +#define SHORT_BITS 16 +#define CHAR_BITS 8 +#define DATA_BLOB_LENGTH 3 +#define MATCH_DATA_LENGTH 8192 +#define ALTERA_REQUEST_SIZE 1024 +#define ALTERA_BUFFER_SIZE (MATCH_DATA_LENGTH + ALTERA_REQUEST_SIZE) + +static u32 altera_bits_req(u32 n) +{ + u32 result = SHORT_BITS; + + if (n == 0) + result = 1; + else { + /* Look for the highest non-zero bit position */ + while ((n & (1 << (SHORT_BITS - 1))) == 0) { + n <<= 1; + --result; + } + } + + return result; +} + +static u32 altera_read_packed(u8 *buffer, u32 bits, u32 *bits_avail, + u32 *in_index) +{ + u32 result = 0; + u32 shift = 0; + u32 databyte = 0; + + while (bits > 0) { + databyte = buffer[*in_index]; + result |= (((databyte >> (CHAR_BITS - *bits_avail)) + & (0xff >> (CHAR_BITS - *bits_avail))) << shift); + + if (bits <= *bits_avail) { + result &= (0xffff >> (SHORT_BITS - (bits + shift))); + *bits_avail -= bits; + bits = 0; + } else { + ++(*in_index); + shift += *bits_avail; + bits -= *bits_avail; + *bits_avail = CHAR_BITS; + } + } + + return result; +} + +u32 altera_shrink(u8 *in, u32 in_length, u8 *out, u32 out_length, s32 version) +{ + u32 i, j, data_length = 0L; + u32 offset, length; + u32 match_data_length = MATCH_DATA_LENGTH; + u32 bits_avail = CHAR_BITS; + u32 in_index = 0L; + + if (version > 0) + --match_data_length; + + for (i = 0; i < out_length; ++i) + out[i] = 0; + + /* Read number of bytes in data. */ + for (i = 0; i < sizeof(in_length); ++i) { + data_length = data_length | ( + altera_read_packed(in, + CHAR_BITS, + &bits_avail, + &in_index) << (i * CHAR_BITS)); + } + + if (data_length > out_length) { + data_length = 0L; + return data_length; + } + + i = 0; + while (i < data_length) { + /* A 0 bit indicates literal data. */ + if (altera_read_packed(in, 1, &bits_avail, + &in_index) == 0) { + for (j = 0; j < DATA_BLOB_LENGTH; ++j) { + if (i < data_length) { + out[i] = (u8)altera_read_packed(in, + CHAR_BITS, + &bits_avail, + &in_index); + i++; + } + } + } else { + /* A 1 bit indicates offset/length to follow. */ + offset = altera_read_packed(in, altera_bits_req((s16) + (i > match_data_length ? + match_data_length : i)), + &bits_avail, + &in_index); + length = altera_read_packed(in, CHAR_BITS, + &bits_avail, + &in_index); + for (j = 0; j < length; ++j) { + if (i < data_length) { + out[i] = out[i - offset]; + i++; + } + } + } + } + + return data_length; +} |
