[PATCH v4 0/4] Minimal build for RISCV

[PATCH v4 0/4] Minimal build for RISCV

[Connor Davis]

Hi all,

This series introduces a minimal build for RISCV. It is based on Bobby's
previous work from last year[0] rebased onto current Xen.

This series provides the patches necessary to get a minimal build
working. The build is "minimal" in the sense that it only supports
building TARGET=head.o. The arch/riscv/head.S is just a simple while(1).

The first 2 patches are mods to non-RISCV bits that enable building a
config with:

  !CONFIG_HAS_NS16550
  !CONFIG_HAS_PASSTHROUGH

respectively. The third patch adds the make/Kconfig boilerplate
alongside head.S and asm-riscv/config.h (head.S references ENTRY
that is defined in asm-riscv/config.h).

The last adds a docker container for doing the build. To build from the
docker container (after creating it locally), you can run the following:

  $ make XEN_TARGET_ARCH=riscv SUBSYSTEMS=xen -C xen tiny64_defconfig
  $ make XEN_TARGET_ARCH=riscv SUBSYSTEMS=xen -C xen TARGET=head.o

[0] https://lore.kernel.org/xen-devel/cover.1579615303.git.bobbyeshleman@gmail.com/

Thanks,
Connor

--
Changes since v3:
  - Dropped "xen: Fix build when !CONFIG_GRANT_TABLE" since this was
    applied by Jan
  - Adjusted Kconfig condition for building NS16550
  - Use bool rather than bool_t
  - Removed riscv memory map, as this should probably be done later once
    the frametable size is figured out
  - Consolidated 64-bit #defines in asm-riscv/config.h
  - Renamed riscv64_defconfig to tiny64_defconfig, added CONFIG_DEBUG
    and CONFIG_DEBUG_INFO
  - Fixed logic/alignment/whitespace issues in Kconfig files
  - Use upstream archlinux riscv64 cross-compiler packages instead of
    custom built toolchain in docker container

Changes since v2:
  - Reduced number of riscv files added to ease review

Changes since v1:
  - Dropped "xen/sched: Fix build when NR_CPUS == 1" since this was
    fixed for 4.15
  - Moved #ifdef-ary around iommu_enabled to iommu.h
  - Moved struct grant_table declaration above ifdef CONFIG_GRANT_TABLE
    instead of defining an empty struct when !CONFIG_GRANT_TABLE
--
Connor Davis (4):
  xen/char: Default HAS_NS16550 to y only for X86 and ARM
  xen/common: Guard iommu symbols with CONFIG_HAS_PASSTHROUGH
  xen: Add files needed for minimal riscv build
  automation: Add container for riscv64 builds

 automation/build/archlinux/riscv64.dockerfile | 19 ++++++++
 automation/scripts/containerize               |  1 +
 config/riscv.mk                               |  4 ++
 xen/Makefile                                  |  8 +++-
 xen/arch/riscv/Kconfig                        | 47 +++++++++++++++++++
 xen/arch/riscv/Kconfig.debug                  |  0
 xen/arch/riscv/Makefile                       |  0
 xen/arch/riscv/Rules.mk                       |  0
 xen/arch/riscv/arch.mk                        | 14 ++++++
 xen/arch/riscv/asm-offsets.c                  |  0
 xen/arch/riscv/configs/tiny64_defconfig       | 13 +++++
 xen/arch/riscv/head.S                         |  6 +++
 xen/common/memory.c                           | 10 ++++
 xen/drivers/char/Kconfig                      |  1 +
 xen/include/asm-riscv/config.h                | 47 +++++++++++++++++++
 xen/include/xen/iommu.h                       |  8 +++-
 16 files changed, 175 insertions(+), 3 deletions(-)
 create mode 100644 automation/build/archlinux/riscv64.dockerfile
 create mode 100644 config/riscv.mk
 create mode 100644 xen/arch/riscv/Kconfig
 create mode 100644 xen/arch/riscv/Kconfig.debug
 create mode 100644 xen/arch/riscv/Makefile
 create mode 100644 xen/arch/riscv/Rules.mk
 create mode 100644 xen/arch/riscv/arch.mk
 create mode 100644 xen/arch/riscv/asm-offsets.c
 create mode 100644 xen/arch/riscv/configs/tiny64_defconfig
 create mode 100644 xen/arch/riscv/head.S
 create mode 100644 xen/include/asm-riscv/config.h


base-commit: d4fb5f166c2bfbaf9ba0de69da0d411288f437a9
-- 
2.31.1

[PATCH v4 1/4] xen/char: Default HAS_NS16550 to y only for X86 and ARM

[Connor Davis]

Defaulting to yes only for X86 and ARM reduces the requirements
for a minimal build when porting new architectures.

Signed-off-by: Connor Davis <connojdavis@gmail.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
---
 xen/drivers/char/Kconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/xen/drivers/char/Kconfig b/xen/drivers/char/Kconfig
index b572305657..2ff5b288e2 100644
--- a/xen/drivers/char/Kconfig
+++ b/xen/drivers/char/Kconfig
@@ -1,5 +1,6 @@
 config HAS_NS16550
 	bool "NS16550 UART driver" if ARM
+	default n if RISCV
 	default y
 	help
 	  This selects the 16550-series UART support. For most systems, say Y.
-- 
2.31.1

[PATCH v4 2/4] xen/common: Guard iommu symbols with CONFIG_HAS_PASSTHROUGH

[Connor Davis]

The variables iommu_enabled and iommu_dont_flush_iotlb are defined in
drivers/passthrough/iommu.c and are referenced in common code, which
causes the link to fail when !CONFIG_HAS_PASSTHROUGH.

Guard references to these variables in common code so that xen
builds when !CONFIG_HAS_PASSTHROUGH.

Signed-off-by: Connor Davis <connojdavis@gmail.com>
---
 xen/common/memory.c     | 10 ++++++++++
 xen/include/xen/iommu.h |  8 +++++++-
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/xen/common/memory.c b/xen/common/memory.c
index b5c70c4b85..72a6b70cb5 100644
--- a/xen/common/memory.c
+++ b/xen/common/memory.c
@@ -294,7 +294,9 @@ int guest_remove_page(struct domain *d, unsigned long gmfn)
     p2m_type_t p2mt;
 #endif
     mfn_t mfn;
+#ifdef CONFIG_HAS_PASSTHROUGH
     bool *dont_flush_p, dont_flush;
+#endif
     int rc;
 
 #ifdef CONFIG_X86
@@ -385,13 +387,17 @@ int guest_remove_page(struct domain *d, unsigned long gmfn)
      * Since we're likely to free the page below, we need to suspend
      * xenmem_add_to_physmap()'s suppressing of IOMMU TLB flushes.
      */
+#ifdef CONFIG_HAS_PASSTHROUGH
     dont_flush_p = &this_cpu(iommu_dont_flush_iotlb);
     dont_flush = *dont_flush_p;
     *dont_flush_p = false;
+#endif
 
     rc = guest_physmap_remove_page(d, _gfn(gmfn), mfn, 0);
 
+#ifdef CONFIG_HAS_PASSTHROUGH
     *dont_flush_p = dont_flush;
+#endif
 
     /*
      * With the lack of an IOMMU on some platforms, domains with DMA-capable
@@ -839,11 +845,13 @@ int xenmem_add_to_physmap(struct domain *d, struct xen_add_to_physmap *xatp,
     xatp->gpfn += start;
     xatp->size -= start;
 
+#ifdef CONFIG_HAS_PASSTHROUGH
     if ( is_iommu_enabled(d) )
     {
        this_cpu(iommu_dont_flush_iotlb) = 1;
        extra.ppage = &pages[0];
     }
+#endif
 
     while ( xatp->size > done )
     {
@@ -868,6 +876,7 @@ int xenmem_add_to_physmap(struct domain *d, struct xen_add_to_physmap *xatp,
         }
     }
 
+#ifdef CONFIG_HAS_PASSTHROUGH
     if ( is_iommu_enabled(d) )
     {
         int ret;
@@ -894,6 +903,7 @@ int xenmem_add_to_physmap(struct domain *d, struct xen_add_to_physmap *xatp,
         if ( unlikely(ret) && rc >= 0 )
             rc = ret;
     }
+#endif
 
     return rc;
 }
diff --git a/xen/include/xen/iommu.h b/xen/include/xen/iommu.h
index 460755df29..904cdf725d 100644
--- a/xen/include/xen/iommu.h
+++ b/xen/include/xen/iommu.h
@@ -51,9 +51,15 @@ static inline bool_t dfn_eq(dfn_t x, dfn_t y)
     return dfn_x(x) == dfn_x(y);
 }
 
-extern bool_t iommu_enable, iommu_enabled;
+extern bool_t iommu_enable;
 extern bool force_iommu, iommu_quarantine, iommu_verbose;
 
+#ifdef CONFIG_HAS_PASSTHROUGH
+extern bool iommu_enabled;
+#else
+#define iommu_enabled false
+#endif
+
 #ifdef CONFIG_X86
 extern enum __packed iommu_intremap {
    /*
-- 
2.31.1

[PATCH v4 3/4] xen: Add files needed for minimal riscv build

[Connor Davis]

Add arch-specific makefiles and configs needed to build for
riscv. Also add a minimal head.S that is a simple infinite loop.
head.o can be built with

$ make XEN_TARGET_ARCH=riscv SUBSYSTEMS=xen -C xen tiny64_defconfig
$ make XEN_TARGET_ARCH=riscv SUBSYSTEMS=xen -C xen TARGET=head.o

No other TARGET is supported at the moment.

Signed-off-by: Connor Davis <connojdavis@gmail.com>
---
 config/riscv.mk                         |  4 +++
 xen/Makefile                            |  8 +++--
 xen/arch/riscv/Kconfig                  | 47 +++++++++++++++++++++++++
 xen/arch/riscv/Kconfig.debug            |  0
 xen/arch/riscv/Makefile                 |  0
 xen/arch/riscv/Rules.mk                 |  0
 xen/arch/riscv/arch.mk                  | 14 ++++++++
 xen/arch/riscv/asm-offsets.c            |  0
 xen/arch/riscv/configs/tiny64_defconfig | 13 +++++++
 xen/arch/riscv/head.S                   |  6 ++++
 xen/include/asm-riscv/config.h          | 47 +++++++++++++++++++++++++
 11 files changed, 137 insertions(+), 2 deletions(-)
 create mode 100644 config/riscv.mk
 create mode 100644 xen/arch/riscv/Kconfig
 create mode 100644 xen/arch/riscv/Kconfig.debug
 create mode 100644 xen/arch/riscv/Makefile
 create mode 100644 xen/arch/riscv/Rules.mk
 create mode 100644 xen/arch/riscv/arch.mk
 create mode 100644 xen/arch/riscv/asm-offsets.c
 create mode 100644 xen/arch/riscv/configs/tiny64_defconfig
 create mode 100644 xen/arch/riscv/head.S
 create mode 100644 xen/include/asm-riscv/config.h

diff --git a/config/riscv.mk b/config/riscv.mk
new file mode 100644
index 0000000000..2b2cc2e63a
--- /dev/null
+++ b/config/riscv.mk
@@ -0,0 +1,4 @@
+CONFIG_RISCV := y
+CONFIG_RISCV_$(XEN_OS) := y
+
+CONFIG_XEN_INSTALL_SUFFIX :=
diff --git a/xen/Makefile b/xen/Makefile
index 9f3be7766d..3a1ff0045b 100644
--- a/xen/Makefile
+++ b/xen/Makefile
@@ -26,7 +26,9 @@ MAKEFLAGS += -rR
 EFI_MOUNTPOINT ?= $(BOOT_DIR)/efi
 
 ARCH=$(XEN_TARGET_ARCH)
-SRCARCH=$(shell echo $(ARCH) | sed -e 's/x86.*/x86/' -e s'/arm\(32\|64\)/arm/g')
+SRCARCH=$(shell echo $(ARCH) | \
+          sed -e 's/x86.*/x86/' -e s'/arm\(32\|64\)/arm/g' \
+              -e s'/riscv.*/riscv/g')
 
 # Don't break if the build process wasn't called from the top level
 # we need XEN_TARGET_ARCH to generate the proper config
@@ -35,7 +37,8 @@ include $(XEN_ROOT)/Config.mk
 # Set ARCH/SUBARCH appropriately.
 export TARGET_SUBARCH  := $(XEN_TARGET_ARCH)
 export TARGET_ARCH     := $(shell echo $(XEN_TARGET_ARCH) | \
-                            sed -e 's/x86.*/x86/' -e s'/arm\(32\|64\)/arm/g')
+                            sed -e 's/x86.*/x86/' -e s'/arm\(32\|64\)/arm/g' \
+                                -e s'/riscv.*/riscv/g')
 
 # Allow someone to change their config file
 export KCONFIG_CONFIG ?= .config
@@ -335,6 +338,7 @@ _clean: delete-unfresh-files
 	$(MAKE) $(clean) xsm
 	$(MAKE) $(clean) crypto
 	$(MAKE) $(clean) arch/arm
+	$(MAKE) $(clean) arch/riscv
 	$(MAKE) $(clean) arch/x86
 	$(MAKE) $(clean) test
 	$(MAKE) -f $(BASEDIR)/tools/kconfig/Makefile.kconfig ARCH=$(ARCH) SRCARCH=$(SRCARCH) clean
diff --git a/xen/arch/riscv/Kconfig b/xen/arch/riscv/Kconfig
new file mode 100644
index 0000000000..bd8381c5e0
--- /dev/null
+++ b/xen/arch/riscv/Kconfig
@@ -0,0 +1,47 @@
+config RISCV
+	def_bool y
+
+config RISCV_64
+	def_bool y
+	select 64BIT
+
+config ARCH_DEFCONFIG
+	string
+	default "arch/riscv/configs/tiny64_defconfig"
+
+menu "Architecture Features"
+
+source "arch/Kconfig"
+
+endmenu
+
+menu "ISA Selection"
+
+choice
+	prompt "Base ISA"
+	default RISCV_ISA_RV64IMA if RISCV_64
+	help
+	  This selects the base ISA extensions that Xen will target.
+
+config RISCV_ISA_RV64IMA
+	bool "RV64IMA"
+	help
+	  Use the RV64I base ISA, plus the "M" and "A" extensions
+	  for integer multiply/divide and atomic instructions, respectively.
+
+endchoice
+
+config RISCV_ISA_C
+	bool "Compressed extension"
+	help
+	  Add "C" to the ISA subsets that the toolchain is allowed to
+	  emit when building Xen, which results in compressed instructions
+	  in the Xen binary.
+
+	  If unsure, say N.
+
+endmenu
+
+source "common/Kconfig"
+
+source "drivers/Kconfig"
diff --git a/xen/arch/riscv/Kconfig.debug b/xen/arch/riscv/Kconfig.debug
new file mode 100644
index 0000000000..e69de29bb2
diff --git a/xen/arch/riscv/Makefile b/xen/arch/riscv/Makefile
new file mode 100644
index 0000000000..e69de29bb2
diff --git a/xen/arch/riscv/Rules.mk b/xen/arch/riscv/Rules.mk
new file mode 100644
index 0000000000..e69de29bb2
diff --git a/xen/arch/riscv/arch.mk b/xen/arch/riscv/arch.mk
new file mode 100644
index 0000000000..53dadb8975
--- /dev/null
+++ b/xen/arch/riscv/arch.mk
@@ -0,0 +1,14 @@
+########################################
+# RISCV-specific definitions
+
+CFLAGS-$(CONFIG_RISCV_64) += -mabi=lp64
+
+riscv-march-$(CONFIG_RISCV_ISA_RV64IMA) := rv64ima
+riscv-march-$(CONFIG_RISCV_ISA_C)       := $(riscv-march-y)c
+
+# Note that -mcmodel=medany is used so that Xen can be mapped
+# into the upper half _or_ the lower half of the address space.
+# -mcmodel=medlow would force Xen into the lower half.
+
+CFLAGS += -march=$(riscv-march-y) -mstrict-align -mcmodel=medany
+CFLAGS += -I$(BASEDIR)/include
diff --git a/xen/arch/riscv/asm-offsets.c b/xen/arch/riscv/asm-offsets.c
new file mode 100644
index 0000000000..e69de29bb2
diff --git a/xen/arch/riscv/configs/tiny64_defconfig b/xen/arch/riscv/configs/tiny64_defconfig
new file mode 100644
index 0000000000..3c9a2ff941
--- /dev/null
+++ b/xen/arch/riscv/configs/tiny64_defconfig
@@ -0,0 +1,13 @@
+# CONFIG_SCHED_CREDIT is not set
+# CONFIG_SCHED_RTDS is not set
+# CONFIG_SCHED_NULL is not set
+# CONFIG_SCHED_ARINC653 is not set
+# CONFIG_TRACEBUFFER is not set
+# CONFIG_HYPFS is not set
+# CONFIG_GRANT_TABLE is not set
+# CONFIG_SPECULATIVE_HARDEN_ARRAY is not set
+
+CONFIG_RISCV_64=y
+CONFIG_DEBUG=y
+CONFIG_DEBUG_INFO=y
+CONFIG_EXPERT=y
diff --git a/xen/arch/riscv/head.S b/xen/arch/riscv/head.S
new file mode 100644
index 0000000000..0dbc27ba75
--- /dev/null
+++ b/xen/arch/riscv/head.S
@@ -0,0 +1,6 @@
+#include <asm/config.h>
+
+        .text
+
+ENTRY(start)
+        j  start
diff --git a/xen/include/asm-riscv/config.h b/xen/include/asm-riscv/config.h
new file mode 100644
index 0000000000..e2ae21de61
--- /dev/null
+++ b/xen/include/asm-riscv/config.h
@@ -0,0 +1,47 @@
+#ifndef __RISCV_CONFIG_H__
+#define __RISCV_CONFIG_H__
+
+#if defined(CONFIG_RISCV_64)
+# define LONG_BYTEORDER 3
+# define ELFSIZE 64
+# define MAX_VIRT_CPUS 128u
+#else
+# error "Unsupported RISCV variant"
+#endif
+
+#define BYTES_PER_LONG (1 << LONG_BYTEORDER)
+#define BITS_PER_LONG  (BYTES_PER_LONG << 3)
+#define POINTER_ALIGN  BYTES_PER_LONG
+
+#define BITS_PER_LLONG 64
+
+/* xen_ulong_t is always 64 bits */
+#define BITS_PER_XEN_ULONG 64
+
+#define CONFIG_RISCV_L1_CACHE_SHIFT 6
+#define CONFIG_PAGEALLOC_MAX_ORDER  18
+#define CONFIG_DOMU_MAX_ORDER       9
+#define CONFIG_HWDOM_MAX_ORDER      10
+
+#define OPT_CONSOLE_STR "dtuart"
+#define INVALID_VCPU_ID MAX_VIRT_CPUS
+
+/* Linkage for RISCV */
+#ifdef __ASSEMBLY__
+#define ALIGN .align 2
+
+#define ENTRY(name)                                \
+  .globl name;                                     \
+  ALIGN;                                           \
+  name:
+#endif
+
+#endif /* __RISCV_CONFIG_H__ */
+/*
+ * Local variables:
+ * mode: C
+ * c-file-style: "BSD"
+ * c-basic-offset: 4
+ * indent-tabs-mode: nil
+ * End:
+ */
-- 
2.31.1

[PATCH v4 4/4] automation: Add container for riscv64 builds

[Connor Davis]

Add a container for cross-compiling xen to riscv64.
This just includes the cross-compiler and necessary packages for
building xen itself (packages for tools, stubdoms, etc., can be
added later).

Signed-off-by: Connor Davis <connojdavis@gmail.com>
---
 automation/build/archlinux/riscv64.dockerfile | 19 +++++++++++++++++++
 automation/scripts/containerize               |  1 +
 2 files changed, 20 insertions(+)
 create mode 100644 automation/build/archlinux/riscv64.dockerfile

diff --git a/automation/build/archlinux/riscv64.dockerfile b/automation/build/archlinux/riscv64.dockerfile
new file mode 100644
index 0000000000..ff8b2b955d
--- /dev/null
+++ b/automation/build/archlinux/riscv64.dockerfile
@@ -0,0 +1,19 @@
+FROM archlinux
+LABEL maintainer.name="The Xen Project" \
+      maintainer.email="xen-devel@lists.xenproject.org"
+
+# Packages needed for the build
+RUN pacman --noconfirm --needed -Syu \
+    base-devel \
+    git \
+    inetutils \
+    riscv64-linux-gnu-binutils \
+    riscv64-linux-gnu-gcc \
+    riscv64-linux-gnu-glibc
+
+# Add compiler path
+ENV CROSS_COMPILE=riscv64-linux-gnu-
+
+RUN useradd --create-home user
+USER user
+WORKDIR /build
diff --git a/automation/scripts/containerize b/automation/scripts/containerize
index b7c81559fb..59edf0ba40 100755
--- a/automation/scripts/containerize
+++ b/automation/scripts/containerize
@@ -26,6 +26,7 @@ BASE="registry.gitlab.com/xen-project/xen"
 case "_${CONTAINER}" in
     _alpine) CONTAINER="${BASE}/alpine:3.12" ;;
     _archlinux|_arch) CONTAINER="${BASE}/archlinux:current" ;;
+    _riscv64) CONTAINER="${BASE}/archlinux:riscv64" ;;
     _centos7) CONTAINER="${BASE}/centos:7" ;;
     _centos72) CONTAINER="${BASE}/centos:7.2" ;;
     _fedora) CONTAINER="${BASE}/fedora:29";;
-- 
2.31.1

Re: [PATCH v4 1/4] xen/char: Default HAS_NS16550 to y only for X86 and ARM

[Jan Beulich]

On 24.05.2021 16:34, Connor Davis wrote:
> Defaulting to yes only for X86 and ARM reduces the requirements
> for a minimal build when porting new architectures.
> 
> Signed-off-by: Connor Davis <connojdavis@gmail.com>
> Reviewed-by: Alistair Francis <alistair.francis@wdc.com>

Acked-by: Jan Beulich <jbeulich@suse.com>

Re: [PATCH v4 1/4] xen/char: Default HAS_NS16550 to y only for X86 and ARM

[Jan Beulich]

On 25.05.2021 09:02, Jan Beulich wrote:
> On 24.05.2021 16:34, Connor Davis wrote:
>> Defaulting to yes only for X86 and ARM reduces the requirements
>> for a minimal build when porting new architectures.
>>
>> Signed-off-by: Connor Davis <connojdavis@gmail.com>
>> Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
> 
> Acked-by: Jan Beulich <jbeulich@suse.com>

Actually, just to make sure: This ...

> --- a/xen/drivers/char/Kconfig
> +++ b/xen/drivers/char/Kconfig
> @@ -1,5 +1,6 @@
>  config HAS_NS16550
>  	bool "NS16550 UART driver" if ARM
> +	default n if RISCV

... won't trigger a kconfig warning prior to the RISCV symbol getting
introduced, will it? (I was about to commit the change when I started
wondering.)

Jan

Re: [PATCH v4 2/4] xen/common: Guard iommu symbols with CONFIG_HAS_PASSTHROUGH

[Jan Beulich]

On 24.05.2021 16:34, Connor Davis wrote:
> The variables iommu_enabled and iommu_dont_flush_iotlb are defined in
> drivers/passthrough/iommu.c and are referenced in common code, which
> causes the link to fail when !CONFIG_HAS_PASSTHROUGH.
> 
> Guard references to these variables in common code so that xen
> builds when !CONFIG_HAS_PASSTHROUGH.
> 
> Signed-off-by: Connor Davis <connojdavis@gmail.com>

Somewhat hesitantly
Acked-by: Jan Beulich <jbeulich@suse.com>
with ...

> --- a/xen/include/xen/iommu.h
> +++ b/xen/include/xen/iommu.h
> @@ -51,9 +51,15 @@ static inline bool_t dfn_eq(dfn_t x, dfn_t y)
>      return dfn_x(x) == dfn_x(y);
>  }
>  
> -extern bool_t iommu_enable, iommu_enabled;
> +extern bool_t iommu_enable;

... just "bool" used here, as I think I did say before. Can be taken
care of while committing, I think.

Jan

Re: [PATCH v4 3/4] xen: Add files needed for minimal riscv build

[Jan Beulich]

On 24.05.2021 16:34, Connor Davis wrote:
> Add arch-specific makefiles and configs needed to build for
> riscv. Also add a minimal head.S that is a simple infinite loop.
> head.o can be built with
> 
> $ make XEN_TARGET_ARCH=riscv SUBSYSTEMS=xen -C xen tiny64_defconfig
> $ make XEN_TARGET_ARCH=riscv SUBSYSTEMS=xen -C xen TARGET=head.o
> 
> No other TARGET is supported at the moment.
> 
> Signed-off-by: Connor Davis <connojdavis@gmail.com>
> ---
>  config/riscv.mk                         |  4 +++
>  xen/Makefile                            |  8 +++--
>  xen/arch/riscv/Kconfig                  | 47 +++++++++++++++++++++++++
>  xen/arch/riscv/Kconfig.debug            |  0
>  xen/arch/riscv/Makefile                 |  0
>  xen/arch/riscv/Rules.mk                 |  0
>  xen/arch/riscv/arch.mk                  | 14 ++++++++
>  xen/arch/riscv/asm-offsets.c            |  0
>  xen/arch/riscv/configs/tiny64_defconfig | 13 +++++++
>  xen/arch/riscv/head.S                   |  6 ++++
>  xen/include/asm-riscv/config.h          | 47 +++++++++++++++++++++++++
>  11 files changed, 137 insertions(+), 2 deletions(-)
>  create mode 100644 config/riscv.mk
>  create mode 100644 xen/arch/riscv/Kconfig
>  create mode 100644 xen/arch/riscv/Kconfig.debug
>  create mode 100644 xen/arch/riscv/Makefile
>  create mode 100644 xen/arch/riscv/Rules.mk
>  create mode 100644 xen/arch/riscv/arch.mk
>  create mode 100644 xen/arch/riscv/asm-offsets.c
>  create mode 100644 xen/arch/riscv/configs/tiny64_defconfig
>  create mode 100644 xen/arch/riscv/head.S
>  create mode 100644 xen/include/asm-riscv/config.h

I think this wants to be accompanied by an addition to ./MAINTAINERS
right away, such that future RISC-V patches can be acked by the
respective designated maintainers, rather than falling under "THE REST".
Question is whether you / we have settled yet who's to become arch
maintainer there.

Jan

Re: [PATCH v4 4/4] automation: Add container for riscv64 builds

[Andrew Cooper]

On 24/05/2021 15:34, Connor Davis wrote:
> Add a container for cross-compiling xen to riscv64.
> This just includes the cross-compiler and necessary packages for
> building xen itself (packages for tools, stubdoms, etc., can be
> added later).
>
> Signed-off-by: Connor Davis <connojdavis@gmail.com>

I've deployed this version of the container, which (surprisingly, not)
is rather smaller than the one with the locally built gcc toolchain.

Therefore, Acked-by: Andrew Cooper <andrew.cooper3@citrix.com> and I'll
commit this right away to make xen.git match reality.

~Andrew

Re: [PATCH v4 3/4] xen: Add files needed for minimal riscv build

[Bob Eshleman]

On 5/25/21 1:48 AM, Jan Beulich wrote:
> On 24.05.2021 16:34, Connor Davis wrote:
>> Add arch-specific makefiles and configs needed to build for
>> riscv. Also add a minimal head.S that is a simple infinite loop.
>> head.o can be built with
>>
>> $ make XEN_TARGET_ARCH=riscv SUBSYSTEMS=xen -C xen tiny64_defconfig
>> $ make XEN_TARGET_ARCH=riscv SUBSYSTEMS=xen -C xen TARGET=head.o
>>
>> No other TARGET is supported at the moment.
>>
>> Signed-off-by: Connor Davis <connojdavis@gmail.com>
>> ---
>>  config/riscv.mk                         |  4 +++
>>  xen/Makefile                            |  8 +++--
>>  xen/arch/riscv/Kconfig                  | 47 +++++++++++++++++++++++++
>>  xen/arch/riscv/Kconfig.debug            |  0
>>  xen/arch/riscv/Makefile                 |  0
>>  xen/arch/riscv/Rules.mk                 |  0
>>  xen/arch/riscv/arch.mk                  | 14 ++++++++
>>  xen/arch/riscv/asm-offsets.c            |  0
>>  xen/arch/riscv/configs/tiny64_defconfig | 13 +++++++
>>  xen/arch/riscv/head.S                   |  6 ++++
>>  xen/include/asm-riscv/config.h          | 47 +++++++++++++++++++++++++
>>  11 files changed, 137 insertions(+), 2 deletions(-)
>>  create mode 100644 config/riscv.mk
>>  create mode 100644 xen/arch/riscv/Kconfig
>>  create mode 100644 xen/arch/riscv/Kconfig.debug
>>  create mode 100644 xen/arch/riscv/Makefile
>>  create mode 100644 xen/arch/riscv/Rules.mk
>>  create mode 100644 xen/arch/riscv/arch.mk
>>  create mode 100644 xen/arch/riscv/asm-offsets.c
>>  create mode 100644 xen/arch/riscv/configs/tiny64_defconfig
>>  create mode 100644 xen/arch/riscv/head.S
>>  create mode 100644 xen/include/asm-riscv/config.h
> 
> I think this wants to be accompanied by an addition to ./MAINTAINERS
> right away, such that future RISC-V patches can be acked by the
> respective designated maintainers, rather than falling under "THE REST".
> Question is whether you / we have settled yet who's to become arch
> maintainer there.
> 
> Jan
> 

I'd like to volunteer myself for this, as I'm slated to continue
with the port indefinitely and would at least like to review
patches.  If Connor has the time, I think it makes sense for him
to be listed there too.

Until we have others (it's just us two right now), it'll be a
lot of us reviewing each other's arch-specific work (in addition to
reviewers elsewhere in the Xen project, of course).

-Bobby

-- 
Bobby Eshleman
SE at Vates SAS

Re: [PATCH v4 2/4] xen/common: Guard iommu symbols with CONFIG_HAS_PASSTHROUGH

[Jan Beulich]

On 25.05.2021 10:44, Jan Beulich wrote:
> On 24.05.2021 16:34, Connor Davis wrote:
>> --- a/xen/include/xen/iommu.h
>> +++ b/xen/include/xen/iommu.h
>> @@ -51,9 +51,15 @@ static inline bool_t dfn_eq(dfn_t x, dfn_t y)
>>      return dfn_x(x) == dfn_x(y);
>>  }
>>  
>> -extern bool_t iommu_enable, iommu_enabled;
>> +extern bool_t iommu_enable;
> 
> ... just "bool" used here, as I think I did say before. Can be taken
> care of while committing, I think.

Actually, while preparing to commit this, I realized this would
better be

--- a/xen/include/xen/iommu.h
+++ b/xen/include/xen/iommu.h
@@ -51,8 +51,12 @@ static inline bool_t dfn_eq(dfn_t x, dfn_t y)
     return dfn_x(x) == dfn_x(y);
 }
 
+#ifdef CONFIG_HAS_PASSTHROUGH
 extern bool_t iommu_enable, iommu_enabled;
 extern bool force_iommu, iommu_quarantine, iommu_verbose;
+#else
+#define iommu_enabled false
+#endif
 
 #ifdef CONFIG_X86
 extern enum __packed iommu_intremap {

Which is what I'm about to commit.

Jan

Re: [PATCH v4 1/4] xen/char: Default HAS_NS16550 to y only for X86 and ARM

[Jan Beulich]

On 25.05.2021 09:06, Jan Beulich wrote:
> On 25.05.2021 09:02, Jan Beulich wrote:
>> On 24.05.2021 16:34, Connor Davis wrote:
>>> Defaulting to yes only for X86 and ARM reduces the requirements
>>> for a minimal build when porting new architectures.
>>>
>>> Signed-off-by: Connor Davis <connojdavis@gmail.com>
>>> Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
>>
>> Acked-by: Jan Beulich <jbeulich@suse.com>
> 
> Actually, just to make sure: This ...
> 
>> --- a/xen/drivers/char/Kconfig
>> +++ b/xen/drivers/char/Kconfig
>> @@ -1,5 +1,6 @@
>>  config HAS_NS16550
>>  	bool "NS16550 UART driver" if ARM
>> +	default n if RISCV
> 
> ... won't trigger a kconfig warning prior to the RISCV symbol getting
> introduced, will it? (I was about to commit the change when I started
> wondering.)

While, not having heard back, I've now verified this myself, I still
decided to leave committing this until the point where it can be committed
together with at least patch 3 here, so there wouldn't be a seemingly
stray reference to RISCV here.

Jan

Re: [PATCH v4 3/4] xen: Add files needed for minimal riscv build

[Connor Davis]

On 5/25/21 12:13 PM, Bob Eshleman wrote:
> On 5/25/21 1:48 AM, Jan Beulich wrote:
>> On 24.05.2021 16:34, Connor Davis wrote:
>>> Add arch-specific makefiles and configs needed to build for
>>> riscv. Also add a minimal head.S that is a simple infinite loop.
>>> head.o can be built with
>>>
>>> $ make XEN_TARGET_ARCH=riscv SUBSYSTEMS=xen -C xen tiny64_defconfig
>>> $ make XEN_TARGET_ARCH=riscv SUBSYSTEMS=xen -C xen TARGET=head.o
>>>
>>> No other TARGET is supported at the moment.
>>>
>>> Signed-off-by: Connor Davis <connojdavis@gmail.com>
>>> ---
>>>   config/riscv.mk                         |  4 +++
>>>   xen/Makefile                            |  8 +++--
>>>   xen/arch/riscv/Kconfig                  | 47 +++++++++++++++++++++++++
>>>   xen/arch/riscv/Kconfig.debug            |  0
>>>   xen/arch/riscv/Makefile                 |  0
>>>   xen/arch/riscv/Rules.mk                 |  0
>>>   xen/arch/riscv/arch.mk                  | 14 ++++++++
>>>   xen/arch/riscv/asm-offsets.c            |  0
>>>   xen/arch/riscv/configs/tiny64_defconfig | 13 +++++++
>>>   xen/arch/riscv/head.S                   |  6 ++++
>>>   xen/include/asm-riscv/config.h          | 47 +++++++++++++++++++++++++
>>>   11 files changed, 137 insertions(+), 2 deletions(-)
>>>   create mode 100644 config/riscv.mk
>>>   create mode 100644 xen/arch/riscv/Kconfig
>>>   create mode 100644 xen/arch/riscv/Kconfig.debug
>>>   create mode 100644 xen/arch/riscv/Makefile
>>>   create mode 100644 xen/arch/riscv/Rules.mk
>>>   create mode 100644 xen/arch/riscv/arch.mk
>>>   create mode 100644 xen/arch/riscv/asm-offsets.c
>>>   create mode 100644 xen/arch/riscv/configs/tiny64_defconfig
>>>   create mode 100644 xen/arch/riscv/head.S
>>>   create mode 100644 xen/include/asm-riscv/config.h
>> I think this wants to be accompanied by an addition to ./MAINTAINERS
>> right away, such that future RISC-V patches can be acked by the
>> respective designated maintainers, rather than falling under "THE REST".
>> Question is whether you / we have settled yet who's to become arch
>> maintainer there.
>>
>> Jan
>>
> I'd like to volunteer myself for this, as I'm slated to continue
> with the port indefinitely and would at least like to review
> patches.  If Connor has the time, I think it makes sense for him
> to be listed there too.
>
> Until we have others (it's just us two right now), it'll be a
> lot of us reviewing each other's arch-specific work (in addition to
> reviewers elsewhere in the Xen project, of course).
>
> -Bobby
>
Jan: can you list Bobby as the maintainer on commit? You can list me as 
well,
but I can't guarantee a time commitment unlike Bobby.

Thanks,
Connor

Re: [PATCH v4 3/4] xen: Add files needed for minimal riscv build

[Jan Beulich]

On 01.06.2021 04:26, Connor Davis wrote:
> 
> 
> On 5/25/21 12:13 PM, Bob Eshleman wrote:
>> On 5/25/21 1:48 AM, Jan Beulich wrote:
>>> On 24.05.2021 16:34, Connor Davis wrote:
>>>> Add arch-specific makefiles and configs needed to build for
>>>> riscv. Also add a minimal head.S that is a simple infinite loop.
>>>> head.o can be built with
>>>>
>>>> $ make XEN_TARGET_ARCH=riscv SUBSYSTEMS=xen -C xen tiny64_defconfig
>>>> $ make XEN_TARGET_ARCH=riscv SUBSYSTEMS=xen -C xen TARGET=head.o
>>>>
>>>> No other TARGET is supported at the moment.
>>>>
>>>> Signed-off-by: Connor Davis <connojdavis@gmail.com>
>>>> ---
>>>>   config/riscv.mk                         |  4 +++
>>>>   xen/Makefile                            |  8 +++--
>>>>   xen/arch/riscv/Kconfig                  | 47 +++++++++++++++++++++++++
>>>>   xen/arch/riscv/Kconfig.debug            |  0
>>>>   xen/arch/riscv/Makefile                 |  0
>>>>   xen/arch/riscv/Rules.mk                 |  0
>>>>   xen/arch/riscv/arch.mk                  | 14 ++++++++
>>>>   xen/arch/riscv/asm-offsets.c            |  0
>>>>   xen/arch/riscv/configs/tiny64_defconfig | 13 +++++++
>>>>   xen/arch/riscv/head.S                   |  6 ++++
>>>>   xen/include/asm-riscv/config.h          | 47 +++++++++++++++++++++++++
>>>>   11 files changed, 137 insertions(+), 2 deletions(-)
>>>>   create mode 100644 config/riscv.mk
>>>>   create mode 100644 xen/arch/riscv/Kconfig
>>>>   create mode 100644 xen/arch/riscv/Kconfig.debug
>>>>   create mode 100644 xen/arch/riscv/Makefile
>>>>   create mode 100644 xen/arch/riscv/Rules.mk
>>>>   create mode 100644 xen/arch/riscv/arch.mk
>>>>   create mode 100644 xen/arch/riscv/asm-offsets.c
>>>>   create mode 100644 xen/arch/riscv/configs/tiny64_defconfig
>>>>   create mode 100644 xen/arch/riscv/head.S
>>>>   create mode 100644 xen/include/asm-riscv/config.h
>>> I think this wants to be accompanied by an addition to ./MAINTAINERS
>>> right away, such that future RISC-V patches can be acked by the
>>> respective designated maintainers, rather than falling under "THE REST".
>>> Question is whether you / we have settled yet who's to become arch
>>> maintainer there.
>>>
>>> Jan
>>>
>> I'd like to volunteer myself for this, as I'm slated to continue
>> with the port indefinitely and would at least like to review
>> patches.  If Connor has the time, I think it makes sense for him
>> to be listed there too.
>>
>> Until we have others (it's just us two right now), it'll be a
>> lot of us reviewing each other's arch-specific work (in addition to
>> reviewers elsewhere in the Xen project, of course).
>>
>> -Bobby
>>
> Jan: can you list Bobby as the maintainer on commit? You can list me as 
> well,
> but I can't guarantee a time commitment unlike Bobby.

Well, actually I did expect a v5 submission with whatever entry you
both deem suitable. Otoh I now realize that patch 1 had my extra
request addressed (by myself) and hence with this one needing just
that entry, I could indeed add that addition myself while committing.
Let me move the mails back to the to-be-committed folder...

Jan

Re: [PATCH v4 3/4] xen: Add files needed for minimal riscv build

[Jan Beulich]

On 24.05.2021 16:34, Connor Davis wrote:
> Add arch-specific makefiles and configs needed to build for
> riscv. Also add a minimal head.S that is a simple infinite loop.
> head.o can be built with
> 
> $ make XEN_TARGET_ARCH=riscv SUBSYSTEMS=xen -C xen tiny64_defconfig
> $ make XEN_TARGET_ARCH=riscv SUBSYSTEMS=xen -C xen TARGET=head.o
> 
> No other TARGET is supported at the moment.

Just to confirm - an actual (even if not functioning) xen binary can't
be linked yet? I ask because that would be the prereq for me to set up
routine (cross) build testing, just like I do for Arm.

Jan

Re: [PATCH v4 3/4] xen: Add files needed for minimal riscv build

[Julien Grall]

Hi,

On 01/06/2021 07:03, Jan Beulich wrote:
> On 01.06.2021 04:26, Connor Davis wrote:
>>
>>
>> On 5/25/21 12:13 PM, Bob Eshleman wrote:
>>> On 5/25/21 1:48 AM, Jan Beulich wrote:
>>>> On 24.05.2021 16:34, Connor Davis wrote:
>>>>> Add arch-specific makefiles and configs needed to build for
>>>>> riscv. Also add a minimal head.S that is a simple infinite loop.
>>>>> head.o can be built with
>>>>>
>>>>> $ make XEN_TARGET_ARCH=riscv SUBSYSTEMS=xen -C xen tiny64_defconfig
>>>>> $ make XEN_TARGET_ARCH=riscv SUBSYSTEMS=xen -C xen TARGET=head.o
>>>>>
>>>>> No other TARGET is supported at the moment.
>>>>>
>>>>> Signed-off-by: Connor Davis <connojdavis@gmail.com>
>>>>> ---
>>>>>    config/riscv.mk                         |  4 +++
>>>>>    xen/Makefile                            |  8 +++--
>>>>>    xen/arch/riscv/Kconfig                  | 47 +++++++++++++++++++++++++
>>>>>    xen/arch/riscv/Kconfig.debug            |  0
>>>>>    xen/arch/riscv/Makefile                 |  0
>>>>>    xen/arch/riscv/Rules.mk                 |  0
>>>>>    xen/arch/riscv/arch.mk                  | 14 ++++++++
>>>>>    xen/arch/riscv/asm-offsets.c            |  0
>>>>>    xen/arch/riscv/configs/tiny64_defconfig | 13 +++++++
>>>>>    xen/arch/riscv/head.S                   |  6 ++++
>>>>>    xen/include/asm-riscv/config.h          | 47 +++++++++++++++++++++++++
>>>>>    11 files changed, 137 insertions(+), 2 deletions(-)
>>>>>    create mode 100644 config/riscv.mk
>>>>>    create mode 100644 xen/arch/riscv/Kconfig
>>>>>    create mode 100644 xen/arch/riscv/Kconfig.debug
>>>>>    create mode 100644 xen/arch/riscv/Makefile
>>>>>    create mode 100644 xen/arch/riscv/Rules.mk
>>>>>    create mode 100644 xen/arch/riscv/arch.mk
>>>>>    create mode 100644 xen/arch/riscv/asm-offsets.c
>>>>>    create mode 100644 xen/arch/riscv/configs/tiny64_defconfig
>>>>>    create mode 100644 xen/arch/riscv/head.S
>>>>>    create mode 100644 xen/include/asm-riscv/config.h
>>>> I think this wants to be accompanied by an addition to ./MAINTAINERS
>>>> right away, such that future RISC-V patches can be acked by the
>>>> respective designated maintainers, rather than falling under "THE REST".
>>>> Question is whether you / we have settled yet who's to become arch
>>>> maintainer there.
>>>>
>>>> Jan
>>>>
>>> I'd like to volunteer myself for this, as I'm slated to continue
>>> with the port indefinitely and would at least like to review
>>> patches.  If Connor has the time, I think it makes sense for him
>>> to be listed there too.
>>>
>>> Until we have others (it's just us two right now), it'll be a
>>> lot of us reviewing each other's arch-specific work (in addition to
>>> reviewers elsewhere in the Xen project, of course).
>>>
>>> -Bobby
>>>
>> Jan: can you list Bobby as the maintainer on commit? You can list me as
>> well,
>> but I can't guarantee a time commitment unlike Bobby.
> 
> Well, actually I did expect a v5 submission with whatever entry you
> both deem suitable. Otoh I now realize that patch 1 had my extra
> request addressed (by myself) and hence with this one needing just
> that entry, I could indeed add that addition myself while committing.
> Let me move the mails back to the to-be-committed folder...

At the risk of being picky, I don't think this should be done of commit. 
Instead, a formal patch should be sent with both maintainers + one of 
the committer acking (or signed-off-by) the proposal.

Cheers,

-- 
Julien Grall

Re: [PATCH v4 3/4] xen: Add files needed for minimal riscv build

[Connor Davis]

On 6/1/21 12:11 AM, Jan Beulich wrote:
> On 24.05.2021 16:34, Connor Davis wrote:
>> Add arch-specific makefiles and configs needed to build for
>> riscv. Also add a minimal head.S that is a simple infinite loop.
>> head.o can be built with
>>
>> $ make XEN_TARGET_ARCH=riscv SUBSYSTEMS=xen -C xen tiny64_defconfig
>> $ make XEN_TARGET_ARCH=riscv SUBSYSTEMS=xen -C xen TARGET=head.o
>>
>> No other TARGET is supported at the moment.
> Just to confirm - an actual (even if not functioning) xen binary can't
> be linked yet? I ask because that would be the prereq for me to set up
> routine (cross) build testing, just like I do for Arm.

That's right. The consensus was that targets and files should be added
incrementally, so I stopped at head.o for now.

Thanks,
Connor

Re: [PATCH v4 3/4] xen: Add files needed for minimal riscv build

[Connor Davis]

On 6/1/21 2:40 AM, Julien Grall wrote:
> Hi,
>
> On 01/06/2021 07:03, Jan Beulich wrote:
>> On 01.06.2021 04:26, Connor Davis wrote:
>>>
>>>
>>> On 5/25/21 12:13 PM, Bob Eshleman wrote:
>>>> On 5/25/21 1:48 AM, Jan Beulich wrote:
>>>>> On 24.05.2021 16:34, Connor Davis wrote:
>>>>>> Add arch-specific makefiles and configs needed to build for
>>>>>> riscv. Also add a minimal head.S that is a simple infinite loop.
>>>>>> head.o can be built with
>>>>>>
>>>>>> $ make XEN_TARGET_ARCH=riscv SUBSYSTEMS=xen -C xen tiny64_defconfig
>>>>>> $ make XEN_TARGET_ARCH=riscv SUBSYSTEMS=xen -C xen TARGET=head.o
>>>>>>
>>>>>> No other TARGET is supported at the moment.
>>>>>>
>>>>>> Signed-off-by: Connor Davis <connojdavis@gmail.com>
>>>>>> ---
>>>>>>    config/riscv.mk                         |  4 +++
>>>>>>    xen/Makefile                            |  8 +++--
>>>>>>    xen/arch/riscv/Kconfig                  | 47 
>>>>>> +++++++++++++++++++++++++
>>>>>>    xen/arch/riscv/Kconfig.debug            |  0
>>>>>>    xen/arch/riscv/Makefile                 |  0
>>>>>>    xen/arch/riscv/Rules.mk                 |  0
>>>>>>    xen/arch/riscv/arch.mk                  | 14 ++++++++
>>>>>>    xen/arch/riscv/asm-offsets.c            |  0
>>>>>>    xen/arch/riscv/configs/tiny64_defconfig | 13 +++++++
>>>>>>    xen/arch/riscv/head.S                   |  6 ++++
>>>>>>    xen/include/asm-riscv/config.h          | 47 
>>>>>> +++++++++++++++++++++++++
>>>>>>    11 files changed, 137 insertions(+), 2 deletions(-)
>>>>>>    create mode 100644 config/riscv.mk
>>>>>>    create mode 100644 xen/arch/riscv/Kconfig
>>>>>>    create mode 100644 xen/arch/riscv/Kconfig.debug
>>>>>>    create mode 100644 xen/arch/riscv/Makefile
>>>>>>    create mode 100644 xen/arch/riscv/Rules.mk
>>>>>>    create mode 100644 xen/arch/riscv/arch.mk
>>>>>>    create mode 100644 xen/arch/riscv/asm-offsets.c
>>>>>>    create mode 100644 xen/arch/riscv/configs/tiny64_defconfig
>>>>>>    create mode 100644 xen/arch/riscv/head.S
>>>>>>    create mode 100644 xen/include/asm-riscv/config.h
>>>>> I think this wants to be accompanied by an addition to ./MAINTAINERS
>>>>> right away, such that future RISC-V patches can be acked by the
>>>>> respective designated maintainers, rather than falling under "THE 
>>>>> REST".
>>>>> Question is whether you / we have settled yet who's to become arch
>>>>> maintainer there.
>>>>>
>>>>> Jan
>>>>>
>>>> I'd like to volunteer myself for this, as I'm slated to continue
>>>> with the port indefinitely and would at least like to review
>>>> patches.  If Connor has the time, I think it makes sense for him
>>>> to be listed there too.
>>>>
>>>> Until we have others (it's just us two right now), it'll be a
>>>> lot of us reviewing each other's arch-specific work (in addition to
>>>> reviewers elsewhere in the Xen project, of course).
>>>>
>>>> -Bobby
>>>>
>>> Jan: can you list Bobby as the maintainer on commit? You can list me as
>>> well,
>>> but I can't guarantee a time commitment unlike Bobby.
>>
>> Well, actually I did expect a v5 submission with whatever entry you
>> both deem suitable. Otoh I now realize that patch 1 had my extra
>> request addressed (by myself) and hence with this one needing just
>> that entry, I could indeed add that addition myself while committing.
>> Let me move the mails back to the to-be-committed folder...
>
> At the risk of being picky, I don't think this should be done of 
> commit. Instead, a formal patch should be sent with both maintainers + 
> one of the committer acking (or signed-off-by) the proposal.

No problem, I will send a v5.

Thanks,
Connor

Re: [PATCH v4 3/4] xen: Add files needed for minimal riscv build

[Alistair Francis]

On Tue, Jun 1, 2021 at 12:26 PM Connor Davis <connojdavis@gmail.com> wrote:
>
>
>
> On 5/25/21 12:13 PM, Bob Eshleman wrote:
> > On 5/25/21 1:48 AM, Jan Beulich wrote:
> >> On 24.05.2021 16:34, Connor Davis wrote:
> >>> Add arch-specific makefiles and configs needed to build for
> >>> riscv. Also add a minimal head.S that is a simple infinite loop.
> >>> head.o can be built with
> >>>
> >>> $ make XEN_TARGET_ARCH=riscv SUBSYSTEMS=xen -C xen tiny64_defconfig
> >>> $ make XEN_TARGET_ARCH=riscv SUBSYSTEMS=xen -C xen TARGET=head.o
> >>>
> >>> No other TARGET is supported at the moment.
> >>>
> >>> Signed-off-by: Connor Davis <connojdavis@gmail.com>
> >>> ---
> >>>   config/riscv.mk                         |  4 +++
> >>>   xen/Makefile                            |  8 +++--
> >>>   xen/arch/riscv/Kconfig                  | 47 +++++++++++++++++++++++++
> >>>   xen/arch/riscv/Kconfig.debug            |  0
> >>>   xen/arch/riscv/Makefile                 |  0
> >>>   xen/arch/riscv/Rules.mk                 |  0
> >>>   xen/arch/riscv/arch.mk                  | 14 ++++++++
> >>>   xen/arch/riscv/asm-offsets.c            |  0
> >>>   xen/arch/riscv/configs/tiny64_defconfig | 13 +++++++
> >>>   xen/arch/riscv/head.S                   |  6 ++++
> >>>   xen/include/asm-riscv/config.h          | 47 +++++++++++++++++++++++++
> >>>   11 files changed, 137 insertions(+), 2 deletions(-)
> >>>   create mode 100644 config/riscv.mk
> >>>   create mode 100644 xen/arch/riscv/Kconfig
> >>>   create mode 100644 xen/arch/riscv/Kconfig.debug
> >>>   create mode 100644 xen/arch/riscv/Makefile
> >>>   create mode 100644 xen/arch/riscv/Rules.mk
> >>>   create mode 100644 xen/arch/riscv/arch.mk
> >>>   create mode 100644 xen/arch/riscv/asm-offsets.c
> >>>   create mode 100644 xen/arch/riscv/configs/tiny64_defconfig
> >>>   create mode 100644 xen/arch/riscv/head.S
> >>>   create mode 100644 xen/include/asm-riscv/config.h
> >> I think this wants to be accompanied by an addition to ./MAINTAINERS
> >> right away, such that future RISC-V patches can be acked by the
> >> respective designated maintainers, rather than falling under "THE REST".
> >> Question is whether you / we have settled yet who's to become arch
> >> maintainer there.
> >>
> >> Jan
> >>
> > I'd like to volunteer myself for this, as I'm slated to continue
> > with the port indefinitely and would at least like to review
> > patches.  If Connor has the time, I think it makes sense for him
> > to be listed there too.
> >
> > Until we have others (it's just us two right now), it'll be a
> > lot of us reviewing each other's arch-specific work (in addition to
> > reviewers elsewhere in the Xen project, of course).
> >
> > -Bobby
> >
> Jan: can you list Bobby as the maintainer on commit? You can list me as
> well,
> but I can't guarantee a time commitment unlike Bobby.

If you need more people you can add me as well. I don't have too much
time to spend here, but I did start the initial Xen port and have a
good understanding of the RISC-V Hypervisor extension.

Alistair

>
> Thanks,
> Connor
>