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authorLinus Torvalds <torvalds@linux-foundation.org>2017-11-15 10:49:15 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2017-11-15 10:49:15 -0800
commitb293fca43be544483b6488d33ad4b3ed55881064 (patch)
treebf9f51967cd3a9fae3a8c1254b715b9c31aa56a6 /lib
parent0ef76878cfcf4d6b64972b283021f576a95d9216 (diff)
parentfbe934d69eb7ed22b59514e9c1fe8871b8b198ec (diff)
Merge tag 'riscv-for-linus-4.15-arch-v9-premerge' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/linux
Pull RISC-V architecture support from Palmer Dabbelt: "This contains the core RISC-V Linux port, which has been through nine rounds of review on various mailing lists. The port is not complete: there's some cleanup patches moving through the review process, a whole bunch of drivers that need some work, and a lot of feature additions that will be needed. The patches contained in this tag have been through nine rounds of review on the various mailing lists. I have some outstanding cleanup patches, but since there's been so much review on these patches I thought it would be best to submit them as-is and then submit explicit cleanup patches so everyone can review them. This first patch set is big enough that it's a bit of a pain to constantly rewrite, and it's caused a few headaches with various contributors. The port is definately a work in progress. While what's there builds and boots with 4.14, it's a bit hard to actually see anything happen because there are no device drivers yet. I maintain a staging branch that contains all the device drivers and cleanup that actually works, but those patches won't all be ready for a while. I'd like to get what we currently have into your tree so everyone can start working from a single base -- of particular importance is allowing the glibc upstreaming process to proceed so we can sort out any possibly lingering user-visible ABI problems we might have. Copied below is the ChangeLog that contains the history of this patch set: (v9) As per suggestions on our v8 patch set, I've split the core architecture code out from our drivers and would like to submit this patch set to be included into linux-next, with the goal being to be merged in during the next merge window. This patch set is based on 4.14-rc2, but if it's better to have it based on something else then I can change it around. This patch set contains just the core arch code for RISC-V, so while it builds an nominally boots, you can't print or take an interrupt so it's not that useful. If you're looking to actually boot a system it would probably be better to use the full patch set listed below. We've collected a handful of tags from reviewers, and the remainder of the patch set only got minimal feedback last time. Here's what changed: - We now use the device tree to initialize the timer driver so it's less tighly coupled with the arch port. - I cleaned up the defconfigs -- there's actually now just one, and it's empty. For now I think we're OK with what the kernel sets as defaults, but I anticipate we'll begin to expand this as people start to use the port more. - The VDSO symbols version is sane. - We WFI while spinning in the boot loop. - A handful of comments have been added. While there are still a handful of FIXMEs in this patch set, we've started to get enough interest from various users and contributors that maintaining an out of tree patch set is starting to become a big burden. Hopefully the patches are good enough to merge now, which will at least get everyone working in a more reasonable manner as we clean up the remaining issues. (v8) I know it may not be the ideal time to submit a patch set right now, as it's the middle of the merge window, but things have calmed down quite a bit in the last month so I thought it would be good to get everyone on the same page. There's been a handful of changes since the last patch set, but most of them are fairly minor: - We changed PAGE_OFFSET to allowing mapping more physical memory on 64-bit systems. This is user configurable, as it triggers a different code model that generates slightly less efficient code. - The device tree binding documentation is back, I'd managed to lose it at some point. - We now pass the atomic64 test suite - The SBI timer driver has been refactored. (v7) It's been a while since my last patch set, but the changes han been fairly minimal: - The PCI cleanup patches have been dropped, we'll do them as a separate patch set later. - We've the Kconfig entries from CONFIG_ISA_* to CONFIG_RISCV_ISA_*, to make grep easier. - There have been a handful of memory model related tweaks in I/O land, particularly relating the PCI and the upcoming platform specification. There are significant comments in the relevant files. This is still a WIP, but I think we're close to getting as good as we're going to get until we end up with some more specifications. (v6) As it's been only a day since the v5 patch set, the changes are pretty minimal: - The patch set is now based on linux-next/master, which I believe is a better base now that we're getting closer to upstream. - EARLY_PRINTK is no longer an option. Since the SBI console is reasonable, there's no penalty to enabling it (and thus no benefit to disabling it). - The mmap syscalls were refactored a bit. (v5) Things have really started to calm down, so this is fairly similar to the v4 patch set. The most interesting changes include: - We've moved back to a single patch set. - SMP support has been fixed, I was accidentally running on a non-SMP configuration. There were various mistakes all over the tree as a result of this. - The cmpxchg syscalls have been removed, as they were deemed a bad idea. As a result, RISC-V Linux systems mandate the A extension. The corresponding Kconfig entry to enable builds on non-A systems has been removed. - A few more atomic fixes: mostly fence changes, but those resulted in a handful of additional macros that were no longer necessary. - riscv_early_sie has been removed. (v4) There have only been a few changes since the v3 patch set: - The cmpxchg64 syscall is no longer enabled on 32-bit systems. It's not possible to provide this on SMP systems, and it's not necessary as glibc knows not to call it. - We provide a ELF_HWCAP so users can determine the ISA of the machine the kernel is running on. - The multi-line comments are in a better form. - There were a handful of headers that could be replaced with the asm-generic versions, and a few unnecessary definitions. - We no longer use printk, but instead use pr_*. - A few Kconfig and defconfig entries have been cleaned up. (v3) A highlight of the changes since the v2 patch set includes: - We've split out all our drivers into separate patch sets, which I've already sent out to the relevant maintainers. I haven't included those patches in this patch set, but some of them are necessary to build our port. - The patch set is now split up differently: rather than being split per directory it is split per topic. Hopefully this will make it easier to review the port on the mailing list. The split is a bit rough, so you probably still want to look at the patch set as a whole. - atomic.h has been completely rewritten and is hopefully now correct. I've attempted to sanitize the various other memory model related code as well, and I think it should all be sane now aside from a handful of FIXMEs commented in the code. - We've changed the cmpexchg syscall to always exist and to not be multiplexed. There is also a VDSO entry for compare and exchange, which allows kernels with the A extension to execute user code without the A extension reasonably fast. - Our user-visible register state now contains enough space for the Q extension for 128-bit floating point, as well as a few words to allow extensibility to future ISA extensions like the eventual V extension for vectors. - A handful of driver cleanups, but these have been split into separate patch sets now so I won't duplicate them here. (v2) A highlight of the changes since the v1 patch set includes: - We've split out our drivers into the right places, which means now there's a lot more patches. I'll be submitting these patches to various subsystem maintainers and including them in any future RISC-V patch sets until they've been merged. - The SBI console driver has been completely rewritten to use the HVC helpers and is now significantly smaller. - We've begun to use weaker barriers as opposed to just the big "fence". There's still some work to do here, specifically: - We need fences in the relaxed MMIO functions. - The non-relaxed MMIO functions are missing R/W bits on their fences. - Many AMOs need the aq and rl bits set. - We now have thread_info in task_struct. As a result, sscratch now contains TP instead of SP. This was necessary because thread_info is no longer on the stack. - A few shared routines have been added that we use instead of creating another arch copy" Reviewed-by: Arnd Bergmann <arnd@arndb.de> * tag 'riscv-for-linus-4.15-arch-v9-premerge' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/linux: RISC-V: Build Infrastructure RISC-V: User-facing API RISC-V: Paging and MMU RISC-V: Device, timer, IRQs, and the SBI RISC-V: Task implementation RISC-V: ELF and module implementation RISC-V: Generic library routines and assembly RISC-V: Atomic and Locking Code RISC-V: Init and Halt Code dt-bindings: RISC-V CPU Bindings lib: Add shared copies of some GCC library routines MAINTAINERS: Add RISC-V
Diffstat (limited to 'lib')
-rw-r--r--lib/Kconfig18
-rw-r--r--lib/Makefile8
-rw-r--r--lib/ashldi3.c44
-rw-r--r--lib/ashrdi3.c46
-rw-r--r--lib/cmpdi2.c42
-rw-r--r--lib/lshrdi3.c45
-rw-r--r--lib/muldi3.c72
-rw-r--r--lib/ucmpdi2.c35
8 files changed, 310 insertions, 0 deletions
diff --git a/lib/Kconfig b/lib/Kconfig
index b1445b22a6de..a2b6745324ab 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -587,3 +587,21 @@ config STRING_SELFTEST
bool "Test string functions"
endmenu
+
+config GENERIC_ASHLDI3
+ bool
+
+config GENERIC_ASHRDI3
+ bool
+
+config GENERIC_LSHRDI3
+ bool
+
+config GENERIC_MULDI3
+ bool
+
+config GENERIC_CMPDI2
+ bool
+
+config GENERIC_UCMPDI2
+ bool
diff --git a/lib/Makefile b/lib/Makefile
index b8f2c16fccaa..136a0b254564 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -248,3 +248,11 @@ UBSAN_SANITIZE_ubsan.o := n
obj-$(CONFIG_SBITMAP) += sbitmap.o
obj-$(CONFIG_PARMAN) += parman.o
+
+# GCC library routines
+obj-$(CONFIG_GENERIC_ASHLDI3) += ashldi3.o
+obj-$(CONFIG_GENERIC_ASHRDI3) += ashrdi3.o
+obj-$(CONFIG_GENERIC_LSHRDI3) += lshrdi3.o
+obj-$(CONFIG_GENERIC_MULDI3) += muldi3.o
+obj-$(CONFIG_GENERIC_CMPDI2) += cmpdi2.o
+obj-$(CONFIG_GENERIC_UCMPDI2) += ucmpdi2.o
diff --git a/lib/ashldi3.c b/lib/ashldi3.c
new file mode 100644
index 000000000000..1b6087db95a5
--- /dev/null
+++ b/lib/ashldi3.c
@@ -0,0 +1,44 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see the file COPYING, or write
+ * to the Free Software Foundation, Inc.
+ */
+
+#include <linux/export.h>
+
+#include <lib/libgcc.h>
+
+long long notrace __ashldi3(long long u, word_type b)
+{
+ DWunion uu, w;
+ word_type bm;
+
+ if (b == 0)
+ return u;
+
+ uu.ll = u;
+ bm = 32 - b;
+
+ if (bm <= 0) {
+ w.s.low = 0;
+ w.s.high = (unsigned int) uu.s.low << -bm;
+ } else {
+ const unsigned int carries = (unsigned int) uu.s.low >> bm;
+
+ w.s.low = (unsigned int) uu.s.low << b;
+ w.s.high = ((unsigned int) uu.s.high << b) | carries;
+ }
+
+ return w.ll;
+}
+EXPORT_SYMBOL(__ashldi3);
diff --git a/lib/ashrdi3.c b/lib/ashrdi3.c
new file mode 100644
index 000000000000..2e67c97ac65a
--- /dev/null
+++ b/lib/ashrdi3.c
@@ -0,0 +1,46 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see the file COPYING, or write
+ * to the Free Software Foundation, Inc.
+ */
+
+#include <linux/export.h>
+
+#include <lib/libgcc.h>
+
+long long notrace __ashrdi3(long long u, word_type b)
+{
+ DWunion uu, w;
+ word_type bm;
+
+ if (b == 0)
+ return u;
+
+ uu.ll = u;
+ bm = 32 - b;
+
+ if (bm <= 0) {
+ /* w.s.high = 1..1 or 0..0 */
+ w.s.high =
+ uu.s.high >> 31;
+ w.s.low = uu.s.high >> -bm;
+ } else {
+ const unsigned int carries = (unsigned int) uu.s.high << bm;
+
+ w.s.high = uu.s.high >> b;
+ w.s.low = ((unsigned int) uu.s.low >> b) | carries;
+ }
+
+ return w.ll;
+}
+EXPORT_SYMBOL(__ashrdi3);
diff --git a/lib/cmpdi2.c b/lib/cmpdi2.c
new file mode 100644
index 000000000000..6d7ebf6c2b86
--- /dev/null
+++ b/lib/cmpdi2.c
@@ -0,0 +1,42 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see the file COPYING, or write
+ * to the Free Software Foundation, Inc.
+ */
+
+#include <linux/export.h>
+
+#include <lib/libgcc.h>
+
+word_type notrace __cmpdi2(long long a, long long b)
+{
+ const DWunion au = {
+ .ll = a
+ };
+ const DWunion bu = {
+ .ll = b
+ };
+
+ if (au.s.high < bu.s.high)
+ return 0;
+ else if (au.s.high > bu.s.high)
+ return 2;
+
+ if ((unsigned int) au.s.low < (unsigned int) bu.s.low)
+ return 0;
+ else if ((unsigned int) au.s.low > (unsigned int) bu.s.low)
+ return 2;
+
+ return 1;
+}
+EXPORT_SYMBOL(__cmpdi2);
diff --git a/lib/lshrdi3.c b/lib/lshrdi3.c
new file mode 100644
index 000000000000..8e845f4bb65f
--- /dev/null
+++ b/lib/lshrdi3.c
@@ -0,0 +1,45 @@
+/*
+ * lib/lshrdi3.c
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see the file COPYING, or write
+ * to the Free Software Foundation, Inc.
+ */
+
+#include <linux/module.h>
+#include <lib/libgcc.h>
+
+long long notrace __lshrdi3(long long u, word_type b)
+{
+ DWunion uu, w;
+ word_type bm;
+
+ if (b == 0)
+ return u;
+
+ uu.ll = u;
+ bm = 32 - b;
+
+ if (bm <= 0) {
+ w.s.high = 0;
+ w.s.low = (unsigned int) uu.s.high >> -bm;
+ } else {
+ const unsigned int carries = (unsigned int) uu.s.high << bm;
+
+ w.s.high = (unsigned int) uu.s.high >> b;
+ w.s.low = ((unsigned int) uu.s.low >> b) | carries;
+ }
+
+ return w.ll;
+}
+EXPORT_SYMBOL(__lshrdi3);
diff --git a/lib/muldi3.c b/lib/muldi3.c
new file mode 100644
index 000000000000..88938543e10a
--- /dev/null
+++ b/lib/muldi3.c
@@ -0,0 +1,72 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see the file COPYING, or write
+ * to the Free Software Foundation, Inc.
+ */
+
+#include <linux/export.h>
+#include <lib/libgcc.h>
+
+#define W_TYPE_SIZE 32
+
+#define __ll_B ((unsigned long) 1 << (W_TYPE_SIZE / 2))
+#define __ll_lowpart(t) ((unsigned long) (t) & (__ll_B - 1))
+#define __ll_highpart(t) ((unsigned long) (t) >> (W_TYPE_SIZE / 2))
+
+/* If we still don't have umul_ppmm, define it using plain C. */
+#if !defined(umul_ppmm)
+#define umul_ppmm(w1, w0, u, v) \
+ do { \
+ unsigned long __x0, __x1, __x2, __x3; \
+ unsigned short __ul, __vl, __uh, __vh; \
+ \
+ __ul = __ll_lowpart(u); \
+ __uh = __ll_highpart(u); \
+ __vl = __ll_lowpart(v); \
+ __vh = __ll_highpart(v); \
+ \
+ __x0 = (unsigned long) __ul * __vl; \
+ __x1 = (unsigned long) __ul * __vh; \
+ __x2 = (unsigned long) __uh * __vl; \
+ __x3 = (unsigned long) __uh * __vh; \
+ \
+ __x1 += __ll_highpart(__x0); /* this can't give carry */\
+ __x1 += __x2; /* but this indeed can */ \
+ if (__x1 < __x2) /* did we get it? */ \
+ __x3 += __ll_B; /* yes, add it in the proper pos */ \
+ \
+ (w1) = __x3 + __ll_highpart(__x1); \
+ (w0) = __ll_lowpart(__x1) * __ll_B + __ll_lowpart(__x0);\
+ } while (0)
+#endif
+
+#if !defined(__umulsidi3)
+#define __umulsidi3(u, v) ({ \
+ DWunion __w; \
+ umul_ppmm(__w.s.high, __w.s.low, u, v); \
+ __w.ll; \
+ })
+#endif
+
+long long notrace __muldi3(long long u, long long v)
+{
+ const DWunion uu = {.ll = u};
+ const DWunion vv = {.ll = v};
+ DWunion w = {.ll = __umulsidi3(uu.s.low, vv.s.low)};
+
+ w.s.high += ((unsigned long) uu.s.low * (unsigned long) vv.s.high
+ + (unsigned long) uu.s.high * (unsigned long) vv.s.low);
+
+ return w.ll;
+}
+EXPORT_SYMBOL(__muldi3);
diff --git a/lib/ucmpdi2.c b/lib/ucmpdi2.c
new file mode 100644
index 000000000000..49a53505c8e3
--- /dev/null
+++ b/lib/ucmpdi2.c
@@ -0,0 +1,35 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see the file COPYING, or write
+ * to the Free Software Foundation, Inc.
+ */
+
+#include <linux/module.h>
+#include <lib/libgcc.h>
+
+word_type __ucmpdi2(unsigned long long a, unsigned long long b)
+{
+ const DWunion au = {.ll = a};
+ const DWunion bu = {.ll = b};
+
+ if ((unsigned int) au.s.high < (unsigned int) bu.s.high)
+ return 0;
+ else if ((unsigned int) au.s.high > (unsigned int) bu.s.high)
+ return 2;
+ if ((unsigned int) au.s.low < (unsigned int) bu.s.low)
+ return 0;
+ else if ((unsigned int) au.s.low > (unsigned int) bu.s.low)
+ return 2;
+ return 1;
+}
+EXPORT_SYMBOL(__ucmpdi2);