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Fix some bugs on RV32 build fail and issue

PATCH Superseded Zong Li 3 participants 9 messages Sep 26, 2018 – Sep 29, 2018

Subsystems (2)
Library code RISC-V

v2 of 4 Superseded Latest is v4 →

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Zong Li

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#0 lore raw

v2 cover Fix some bugs on RV32 build fail and issue

This patches contain the modificaion as follows:
1. Fix up the building fail on RV32.
2. Add umoddi3 and udivmoddi4 functions for RV32.
3. Fix ioremap problem on RV32.

Changes in v2:
- Retain the copyright notices from libgcc in umoddi3.c and udivmoddi4.c.

Vincent Chen (1):
RISC-V: Avoid corrupting the upper 32-bit of phys_addr_t in ioremap

Zong Li (4):
RISC-V: Build tishift only on 64-bit
RISC-V: Use swiotlb on RV64 only
lib: Add umoddi3 and udivmoddi4 of GCC library routines
RISC-V: Select GENERIC_LIB_UMODDI3 on RV32

 arch/riscv/Kconfig        |   1 +
 arch/riscv/kernel/setup.c |   3 +
 arch/riscv/lib/Makefile   |   3 +-
 arch/riscv/mm/ioremap.c   |   2 +-
 lib/Kconfig               |   3 +
 lib/Makefile              |   1 +
 lib/udivmoddi4.c          | 309 ++++++++++++++++++++++++++++++++++++++++++++++
 lib/umoddi3.c             |  34 +++++
 8 files changed, 354 insertions(+), 2 deletions(-)
 create mode 100644 lib/udivmoddi4.c
 create mode 100644 lib/umoddi3.c
Signature · 1 line
2.7.4
author
#1 lore raw

PATCH v2 1/5 RISC-V: Build tishift only on 64-bit

Only RV64 supports 128 integer size.

Signed-off-by Zong Li <[email protected]>
---
 arch/riscv/lib/Makefile | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
arch/riscv/lib/Makefile +2 -1
index 445ec84..5739bd0 100644
@@ -2,6 +2,7 @@ lib-y	+= delay.o
 lib-y	+= memcpy.o
 lib-y	+= memset.o
 lib-y	+= uaccess.o
-lib-y	+= tishift.o
+
+lib-(CONFIG_64BIT) += tishift.o
 
 lib-$(CONFIG_32BIT) += udivdi3.o
Signature · 1 line
2.7.4
author
#2 lore raw

PATCH v2 2/5 RISC-V: Use swiotlb on RV64 only

In reply to Zong Li

Only RV64 supports swiotlb.

Signed-off-by Zong Li <[email protected]>
---
 arch/riscv/kernel/setup.c | 3 +++
 1 file changed, 3 insertions(+)
arch/riscv/kernel/setup.c +3 -0
index aee6031..872a280 100644
@@ -227,7 +227,10 @@ void __init setup_arch(char **cmdline_p)
 	setup_bootmem();
 	paging_init();
 	unflatten_device_tree();
+
+#ifdef CONFIG_64bit
 	swiotlb_init(1);
+#endif
 
 #ifdef CONFIG_SMP
 	setup_smp();
Signature · 1 line
2.7.4
author
#3 lore raw

PATCH v2 3/5 lib: Add umoddi3 and udivmoddi4 of GCC library routines

In reply to Zong Li

Add umoddi3 and udivmoddi4 support for 32-bit.

The RV32 need the umoddi3 to do modulo when the operands are long long type, like other libraries implementation such as ucmpdi2, lshrdi3 and so on.

I encounter the undefined reference 'umoddi3' when I use the in house dma driver, although it is in house driver, but I think that umoddi3 is a common function for RV32.

The udivmoddi4 and umoddi3 are copies from libgcc in gcc. There are other functions use the udivmoddi4 in libgcc, so I separate the umoddi3 and udivmoddi4 for flexible extension in the future.

Signed-off-by Zong Li <[email protected]>
---
 lib/Kconfig      |   3 +
 lib/Makefile     |   1 +
 lib/udivmoddi4.c | 309 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 lib/umoddi3.c    |  34 ++++++
 4 files changed, 347 insertions(+)
 create mode 100644 lib/udivmoddi4.c
 create mode 100644 lib/umoddi3.c
lib/Kconfig +3 -0
index a3928d4..d82f206 100644
@@ -621,3 +621,6 @@ config GENERIC_LIB_CMPDI2
 
 config GENERIC_LIB_UCMPDI2
 	bool
+
+config GENERIC_LIB_UMODDI3
+	bool
lib/Makefile +1 -0
index ca3f7eb..51bf24d 100644
@@ -271,3 +271,4 @@ obj-$(CONFIG_GENERIC_LIB_LSHRDI3) += lshrdi3.o
 obj-$(CONFIG_GENERIC_LIB_MULDI3) += muldi3.o
 obj-$(CONFIG_GENERIC_LIB_CMPDI2) += cmpdi2.o
 obj-$(CONFIG_GENERIC_LIB_UCMPDI2) += ucmpdi2.o
+obj-$(CONFIG_GENERIC_LIB_UMODDI3) += umoddi3.o udivmoddi4.o
lib/udivmoddi4.c new file +309 -0

309 lines not on this page · raw message

lib/umoddi3.c new file +34 -0
new file mode 100644
index 0000000..0134696
@@ -0,0 +1,34 @@
+/*
+ * 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 3, 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.
+ *
+ * Under Section 7 of GPL version 3, you are granted additional
+ * permissions described in the GCC Runtime Library Exception, version
+ * 3.1, as published by the Free Software Foundation.
+ *
+ * You should have received a copy of the GNU General Public License and
+ * a copy of the GCC Runtime Library Exception along with this program;
+ * see the files COPYING3 and COPYING.RUNTIME respectively.
+ */
+
+#include <linux/module.h>
+#include <linux/libgcc.h>
+
+extern unsigned long long __udivmoddi4(unsigned long long u,
+				       unsigned long long v,
+				       unsigned long long *rp);
+
+unsigned long long __umoddi3(unsigned long long u, unsigned long long v)
+{
+	unsigned long long w;
+	(void)__udivmoddi4(u, v, &w);
+	return w;
+}
+EXPORT_SYMBOL(__umoddi3);
Signature · 1 line
2.7.4
author
#5 lore raw

PATCH v2 4/5 RISC-V: Select GENERIC_LIB_UMODDI3 on RV32

In reply to Zong Li

On 32-bit, it need to use __umoddi3 by some drivers.

Signed-off-by Zong Li <[email protected]>
---
 arch/riscv/Kconfig | 1 +
 1 file changed, 1 insertion(+)
arch/riscv/Kconfig +1 -0
index a344980..dc262fa 100644
@@ -108,6 +108,7 @@ config ARCH_RV32I
 	select GENERIC_LIB_ASHRDI3
 	select GENERIC_LIB_LSHRDI3
 	select GENERIC_LIB_UCMPDI2
+	select GENERIC_LIB_UMODDI3
 
 config ARCH_RV64I
 	bool "RV64I"
Signature · 1 line
2.7.4
author
#6 lore raw

PATCH v2 5/5 RISC-V: Avoid corrupting the upper 32-bit of phys_addr_t in ioremap

In reply to Zong Li

From: Vincent Chen <[email protected]>

For 32bit, the upper 32-bit of phys_addr_t will be flushed to zero after AND with PAGE_MASK because the data type of PAGE_MASK is unsigned long. To fix this problem, the page alignment is done by subtracting the page offset instead of AND with PAGE_MASK.

Signed-off-by Vincent Chen <[email protected]>
---
 arch/riscv/mm/ioremap.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
arch/riscv/mm/ioremap.c +1 -1
index 70ef272..bd2f2db 100644
@@ -42,7 +42,7 @@ static void __iomem *__ioremap_caller(phys_addr_t addr, size_t size,
 
 	/* Page-align mappings */
 	offset = addr & (~PAGE_MASK);
-	addr &= PAGE_MASK;
+	addr -= offset;
 	size = PAGE_ALIGN(size + offset);
 
 	area = get_vm_area_caller(size, VM_IOREMAP, caller);
Signature · 1 line
2.7.4
#4 lore raw

Re: [PATCH v2 3/5] lib: Add umoddi3 and udivmoddi4 of GCC library routines

In reply to Zong Li

lib/udivmoddi4.c

Quoted 6 lines · Zong Li
lib/udivmoddi4.c new file +0 -0
new file mode 100644
index 0000000..6518b3a
@@ -0,0 +1,309 @@

needs and SPDX tag.

lib/udivmoddi4.c line 5

Quoted 5 lines
lib/udivmoddi4.c new file +5 -0
+/*
+ * 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 3, or (at your option) any later
+ * version.

We can't take GPLv3 code for the kernel.

lib/udivmoddi4.c line 18

Quoted 7 lines
lib/udivmoddi4.c new file +7 -0
+ * Under Section 7 of GPL version 3, you are granted additional
+ * permissions described in the GCC Runtime Library Exception, version
+ * 3.1, as published by the Free Software Foundation.
+ *
+ * You should have received a copy of the GNU General Public License and
+ * a copy of the GCC Runtime Library Exception along with this program;
+ * see the files COPYING3 and COPYING.RUNTIME respectively.

unless this exception somehow counts (which I doubt), but for that we'd actually need it in the tree.

#7 lore raw
In reply to Zong Li
Quoted 17 lines · zongbox at gmail.com

This patches contain the modificaion as follows:
1. Fix up the building fail on RV32.
2. Add umoddi3 and udivmoddi4 functions for RV32.
3. Fix ioremap problem on RV32.

Changes in v2:
- Retain the copyright notices from libgcc in umoddi3.c and udivmoddi4.c.

Vincent Chen (1):
RISC-V: Avoid corrupting the upper 32-bit of phys_addr_t in ioremap

Zong Li (4):
RISC-V: Build tishift only on 64-bit
RISC-V: Use swiotlb on RV64 only
lib: Add umoddi3 and udivmoddi4 of GCC library routines
RISC-V: Select GENERIC_LIB_UMODDI3 on RV32

Quoted 11 lines
 arch/riscv/Kconfig        |   1 +
 arch/riscv/kernel/setup.c |   3 +
 arch/riscv/lib/Makefile   |   3 +-
 arch/riscv/mm/ioremap.c   |   2 +-
 lib/Kconfig               |   3 +
 lib/Makefile              |   1 +
 lib/udivmoddi4.c          | 309 ++++++++++++++++++++++++++++++++++++++++++++++
 lib/umoddi3.c             |  34 +++++
 8 files changed, 354 insertions(+), 2 deletions(-)
 create mode 100644 lib/udivmoddi4.c
 create mode 100644 lib/umoddi3.c

I like what this does, but there's a license issue here that Christoph pointed out. It'd be great to have RV32I systems booting 4.19, do you think there's a chance you can sort this out next week so we can get it into the last RC? That would help with the rv32i glibc process, as we'll actually be able to boot an upstream kernel.

It looks like the functions we have an issue with come from libgcc2.c, which doesn't change very much. As far as I can tell we might be able to get away with these functions from 4.2.1, which was licensed under the GPLv2. Here's the relevant functions on GCC's github mirror

    https://github.com/gcc-mirror/gcc/blob/gcc-4_2_1-release/gcc/libgcc2.c#L559
    https://github.com/gcc-mirror/gcc/blob/gcc-4_2_1-release/gcc/libgcc2.c#L844

These look very similar to what you send out. As far as I can tell, if you base your code on the GPLv2 version then this should be fine to include.

Thanks!

author
#8 lore raw

Palmer Dabbelt <[email protected]> ? 2018?9?29? ?? ??7:52???

Quoted 42 lines · zongbox at gmail.com
Quoted 17 lines

This patches contain the modificaion as follows:
1. Fix up the building fail on RV32.
2. Add umoddi3 and udivmoddi4 functions for RV32.
3. Fix ioremap problem on RV32.

Changes in v2:
- Retain the copyright notices from libgcc in umoddi3.c and udivmoddi4.c.

Vincent Chen (1):
RISC-V: Avoid corrupting the upper 32-bit of phys_addr_t in ioremap

Zong Li (4):
RISC-V: Build tishift only on 64-bit
RISC-V: Use swiotlb on RV64 only
lib: Add umoddi3 and udivmoddi4 of GCC library routines
RISC-V: Select GENERIC_LIB_UMODDI3 on RV32

Quoted 11 lines
 arch/riscv/Kconfig        |   1 +
 arch/riscv/kernel/setup.c |   3 +
 arch/riscv/lib/Makefile   |   3 +-
 arch/riscv/mm/ioremap.c   |   2 +-
 lib/Kconfig               |   3 +
 lib/Makefile              |   1 +
 lib/udivmoddi4.c          | 309 ++++++++++++++++++++++++++++++++++++++++++++++
 lib/umoddi3.c             |  34 +++++
 8 files changed, 354 insertions(+), 2 deletions(-)
 create mode 100644 lib/udivmoddi4.c
 create mode 100644 lib/umoddi3.c

I like what this does, but there's a license issue here that Christoph pointed out. It'd be great to have RV32I systems booting 4.19, do you think there's a chance you can sort this out next week so we can get it into the last RC? That would help with the rv32i glibc process, as we'll actually be able to boot an upstream kernel.

It looks like the functions we have an issue with come from libgcc2.c, which doesn't change very much. As far as I can tell we might be able to get away with these functions from 4.2.1, which was licensed under the GPLv2. Here's the relevant functions on GCC's github mirror

Quoted 7 lines
    https://github.com/gcc-mirror/gcc/blob/gcc-4_2_1-release/gcc/libgcc2.c#L559
    https://github.com/gcc-mirror/gcc/blob/gcc-4_2_1-release/gcc/libgcc2.c#L844

These look very similar to what you send out. As far as I can tell, if you base your code on the GPLv2 version then this should be fine to include.

Thanks!

Thanks for the help and useful information. I will modify the implementation and submit the next version.