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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
commit4352b8aee98005853aa63f57d6377282de17a33f (patch)
tree27614d7a9ef05c32d089004e104364ce42324837 /arch/powerpc/boot/decompress.c
downloadlinux-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/powerpc/boot/decompress.c')
-rw-r--r--arch/powerpc/boot/decompress.c143
1 files changed, 143 insertions, 0 deletions
diff --git a/arch/powerpc/boot/decompress.c b/arch/powerpc/boot/decompress.c
new file mode 100644
index 000000000..6835cb53f
--- /dev/null
+++ b/arch/powerpc/boot/decompress.c
@@ -0,0 +1,143 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Wrapper around the kernel's pre-boot decompression library.
+ *
+ * Copyright (C) IBM Corporation 2016.
+ */
+
+#include "elf.h"
+#include "page.h"
+#include "string.h"
+#include "stdio.h"
+#include "ops.h"
+#include "reg.h"
+#include "types.h"
+
+/*
+ * The decompressor_*.c files play #ifdef games so they can be used in both
+ * pre-boot and regular kernel code. We need these definitions to make the
+ * includes work.
+ */
+
+#define STATIC static
+#define INIT
+
+/*
+ * The build process will copy the required zlib source files and headers
+ * out of lib/ and "fix" the includes so they do not pull in other kernel
+ * headers.
+ */
+
+#ifdef CONFIG_KERNEL_GZIP
+# include "decompress_inflate.c"
+#endif
+
+#ifdef CONFIG_KERNEL_XZ
+# include "xz_config.h"
+# include "../../../lib/decompress_unxz.c"
+#endif
+
+/* globals for tracking the state of the decompression */
+static unsigned long decompressed_bytes;
+static unsigned long limit;
+static unsigned long skip;
+static char *output_buffer;
+
+/*
+ * flush() is called by __decompress() when the decompressor's scratch buffer is
+ * full.
+ */
+static long flush(void *v, unsigned long buffer_size)
+{
+ unsigned long end = decompressed_bytes + buffer_size;
+ unsigned long size = buffer_size;
+ unsigned long offset = 0;
+ char *in = v;
+ char *out;
+
+ /*
+ * if we hit our decompression limit, we need to fake an error to abort
+ * the in-progress decompression.
+ */
+ if (decompressed_bytes >= limit)
+ return -1;
+
+ /* skip this entire block */
+ if (end <= skip) {
+ decompressed_bytes += buffer_size;
+ return buffer_size;
+ }
+
+ /* skip some data at the start, but keep the rest of the block */
+ if (decompressed_bytes < skip && end > skip) {
+ offset = skip - decompressed_bytes;
+
+ in += offset;
+ size -= offset;
+ decompressed_bytes += offset;
+ }
+
+ out = &output_buffer[decompressed_bytes - skip];
+ size = min(decompressed_bytes + size, limit) - decompressed_bytes;
+
+ memcpy(out, in, size);
+ decompressed_bytes += size;
+
+ return buffer_size;
+}
+
+static void print_err(char *s)
+{
+ /* suppress the "error" when we terminate the decompressor */
+ if (decompressed_bytes >= limit)
+ return;
+
+ printf("Decompression error: '%s'\n\r", s);
+}
+
+/**
+ * partial_decompress - decompresses part or all of a compressed buffer
+ * @inbuf: input buffer
+ * @input_size: length of the input buffer
+ * @outbuf: output buffer
+ * @output_size: length of the output buffer
+ * @_skip: number of output bytes to ignore
+ *
+ * This function takes compressed data from inbuf, decompresses and write it to
+ * outbuf. Once output_size bytes are written to the output buffer, or the
+ * stream is exhausted the function will return the number of bytes that were
+ * decompressed. Otherwise it will return whatever error code the decompressor
+ * reported (NB: This is specific to each decompressor type).
+ *
+ * The skip functionality is mainly there so the program and discover
+ * the size of the compressed image so that it can ask firmware (if present)
+ * for an appropriately sized buffer.
+ */
+long partial_decompress(void *inbuf, unsigned long input_size,
+ void *outbuf, unsigned long output_size, unsigned long _skip)
+{
+ int ret;
+
+ /*
+ * The skipped bytes needs to be included in the size of data we want
+ * to decompress.
+ */
+ output_size += _skip;
+
+ decompressed_bytes = 0;
+ output_buffer = outbuf;
+ limit = output_size;
+ skip = _skip;
+
+ ret = __decompress(inbuf, input_size, NULL, flush, outbuf,
+ output_size, NULL, print_err);
+
+ /*
+ * If decompression was aborted due to an actual error rather than
+ * a fake error that we used to abort, then we should report it.
+ */
+ if (decompressed_bytes < limit)
+ return ret;
+
+ return decompressed_bytes - skip;
+}