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* [PATCH v3 0/4] Initial support for Power
@ 2023-06-13 14:49 Shawn Anastasio
  2023-06-13 14:49 ` [PATCH v3 1/4] automation: Add container for ppc64le builds Shawn Anastasio
                   ` (3 more replies)
  0 siblings, 4 replies; 11+ messages in thread
From: Shawn Anastasio @ 2023-06-13 14:49 UTC (permalink / raw)
  To: xen-devel
  Cc: tpearson, Shawn Anastasio, Doug Goldstein, Stefano Stabellini,
	Andrew Cooper, George Dunlap, Jan Beulich, Julien Grall, Wei Liu

Hello all,

This patch series adds support for building a minimal image
(head.o-only) for Power ISA 2.07B+ (POWER8+) systems. The first patch
boots to an infinite loop and the second adds early serial console
support on pseries VMs, with bare metal support planned next.

Since Xen previously had support for a much older version of the ISA in
version 3.2.3, we were able to carry over some headers and support
routines from that version. Unlike that initial port though, this effort
focuses solely on POWER8+ CPUs that are capable of running in Little
Endian mode.

With an appropriate powerpc64le-linux-gnu cross-toolchain, the minimal
image can be built with:

$ make XEN_TARGET_ARCH=ppc64 -C xen openpower_defconfig
$ make XEN_TARGET_ARCH=ppc64 SUBSYSTEMS=xen -C xen build

The resulting head.o can then be booted in a standard QEMU/pseries VM:

$ qemu-system-ppc64 -M pseries-5.2 -m 256M -kernel xen/xen \
	-vga none -serial mon:stdio -nographic

Thanks,
Shawn

--
Changes from v3:
  - Fix formatting of MAINTAINERS patch

Changes from v2:
  - Add ppc64le cross-build container patch
  - Add ppc64le cross build CI job patch
  - Drop serial output patch (will be in future patch series)
  - Drop setup.c and unneeded headers from minimal build patch
  - Fixed ordering of MAINTAINERS patch + add F: line
  - Fix config/ppc64.mk option names
  - Clarify Kconfig Baseline ISA option help strings

Shawn Anastasio (4):
  automation: Add container for ppc64le builds
  xen: Add files needed for minimal ppc64le build
  automation: Add ppc64le cross-build jobs
  maintainers: Add ppc64 maintainer

 MAINTAINERS                                   |   4 +
 .../build/debian/bullseye-ppc64le.dockerfile  |  28 +++
 automation/gitlab-ci/build.yaml               |  60 ++++++
 automation/scripts/containerize               |   1 +
 config/ppc64.mk                               |   5 +
 xen/Makefile                                  |   5 +-
 xen/arch/ppc/Kconfig                          |  42 +++++
 xen/arch/ppc/Kconfig.debug                    |   0
 xen/arch/ppc/Makefile                         |  16 ++
 xen/arch/ppc/Rules.mk                         |   0
 xen/arch/ppc/arch.mk                          |  11 ++
 xen/arch/ppc/configs/openpower_defconfig      |  13 ++
 xen/arch/ppc/include/asm/config.h             |  63 +++++++
 xen/arch/ppc/include/asm/page-bits.h          |   7 +
 xen/arch/ppc/ppc64/Makefile                   |   1 +
 xen/arch/ppc/ppc64/asm-offsets.c              |   0
 xen/arch/ppc/ppc64/head.S                     |  27 +++
 xen/arch/ppc/xen.lds.S                        | 173 ++++++++++++++++++
 18 files changed, 454 insertions(+), 2 deletions(-)
 create mode 100644 automation/build/debian/bullseye-ppc64le.dockerfile
 create mode 100644 config/ppc64.mk
 create mode 100644 xen/arch/ppc/Kconfig
 create mode 100644 xen/arch/ppc/Kconfig.debug
 create mode 100644 xen/arch/ppc/Makefile
 create mode 100644 xen/arch/ppc/Rules.mk
 create mode 100644 xen/arch/ppc/arch.mk
 create mode 100644 xen/arch/ppc/configs/openpower_defconfig
 create mode 100644 xen/arch/ppc/include/asm/config.h
 create mode 100644 xen/arch/ppc/include/asm/page-bits.h
 create mode 100644 xen/arch/ppc/ppc64/Makefile
 create mode 100644 xen/arch/ppc/ppc64/asm-offsets.c
 create mode 100644 xen/arch/ppc/ppc64/head.S
 create mode 100644 xen/arch/ppc/xen.lds.S

-- 
2.30.2



^ permalink raw reply	[flat|nested] 11+ messages in thread
* [PATCH v3 1/4] automation: Add container for ppc64le builds
  2023-06-13 14:49 [PATCH v3 0/4] Initial support for Power Shawn Anastasio
@ 2023-06-13 14:49 ` Shawn Anastasio
  2023-06-16 15:29   ` Andrew Cooper
  2023-06-13 14:50 ` [PATCH v3 2/4] xen: Add files needed for minimal ppc64le build Shawn Anastasio
                   ` (2 subsequent siblings)
  3 siblings, 1 reply; 11+ messages in thread
From: Shawn Anastasio @ 2023-06-13 14:49 UTC (permalink / raw)
  To: xen-devel
  Cc: tpearson, Shawn Anastasio, Doug Goldstein, Stefano Stabellini,
	Shawn Anastasio

Add a container for cross-compiling xen for ppc64le.

Signed-off-by: Shawn Anastasio <sanastasio@raptorengineering.com>
---
 .../build/debian/bullseye-ppc64le.dockerfile  | 28 +++++++++++++++++++
 automation/scripts/containerize               |  1 +
 2 files changed, 29 insertions(+)
 create mode 100644 automation/build/debian/bullseye-ppc64le.dockerfile

diff --git a/automation/build/debian/bullseye-ppc64le.dockerfile b/automation/build/debian/bullseye-ppc64le.dockerfile
new file mode 100644
index 0000000000..8a87631b52
--- /dev/null
+++ b/automation/build/debian/bullseye-ppc64le.dockerfile
@@ -0,0 +1,28 @@
+FROM debian:bullseye-slim
+LABEL maintainer.name="The Xen Project" \
+      maintainer.email="xen-devel@lists.xenproject.org"
+
+ENV DEBIAN_FRONTEND=noninteractive
+ENV USER root
+
+# Add compiler path
+ENV CROSS_COMPILE powerpc64le-linux-gnu-
+
+RUN mkdir /build
+WORKDIR /build
+
+# build depends
+RUN apt-get update && \
+    apt-get --quiet --yes --no-install-recommends install \
+        bison \
+        build-essential \
+        checkpolicy \
+        flex \
+        gawk \
+        gcc-powerpc64le-linux-gnu \
+        make \
+        python3-minimal \
+        && \
+        apt-get autoremove -y && \
+        apt-get clean && \
+        rm -rf /var/lib/apt/lists* /tmp/* /var/tmp/*
diff --git a/automation/scripts/containerize b/automation/scripts/containerize
index 5476ff0ea1..6d46f63665 100755
--- a/automation/scripts/containerize
+++ b/automation/scripts/containerize
@@ -33,6 +33,7 @@ case "_${CONTAINER}" in
     _focal) CONTAINER="${BASE}/ubuntu:focal" ;;
     _jessie) CONTAINER="${BASE}/debian:jessie" ;;
     _jessie-i386) CONTAINER="${BASE}/debian:jessie-i386" ;;
+    _bullseye-ppc64le) CONTAINER="${BASE}/debian:bullseye-ppc64le" ;;
     _stretch|_) CONTAINER="${BASE}/debian:stretch" ;;
     _stretch-i386) CONTAINER="${BASE}/debian:stretch-i386" ;;
     _buster-gcc-ibt) CONTAINER="${BASE}/debian:buster-gcc-ibt" ;;
-- 
2.30.2



^ permalink raw reply related	[flat|nested] 11+ messages in thread
* [PATCH v3 2/4] xen: Add files needed for minimal ppc64le build
  2023-06-13 14:49 [PATCH v3 0/4] Initial support for Power Shawn Anastasio
  2023-06-13 14:49 ` [PATCH v3 1/4] automation: Add container for ppc64le builds Shawn Anastasio
@ 2023-06-13 14:50 ` Shawn Anastasio
  2023-06-14 15:51   ` Jan Beulich
  2023-06-13 14:50 ` [PATCH v3 3/4] automation: Add ppc64le cross-build jobs Shawn Anastasio
  2023-06-13 14:50 ` [PATCH v3 4/4] maintainers: Add ppc64 maintainer Shawn Anastasio
  3 siblings, 1 reply; 11+ messages in thread
From: Shawn Anastasio @ 2023-06-13 14:50 UTC (permalink / raw)
  To: xen-devel
  Cc: tpearson, Shawn Anastasio, Andrew Cooper, George Dunlap,
	Jan Beulich, Julien Grall, Stefano Stabellini, Wei Liu,
	Shawn Anastasio

Add the build system changes required to build for ppc64le (POWER8+).
As of now the resulting image simply boots to an infinite loop.

$ make XEN_TARGET_ARCH=ppc64 -C xen openpower_defconfig
$ make XEN_TARGET_ARCH=ppc64 SUBSYSTEMS=xen -C xen build

This port targets POWER8+ CPUs running in Little Endian mode specifically,
and does not boot on older machines. Additionally, this initial skeleton
only implements the PaPR/pseries boot protocol which allows it to be
booted in a standard QEMU virtual machine:

$ qemu-system-ppc64 -M pseries-5.2 -m 256M -kernel xen/xen

Signed-off-by: Shawn Anastasio <sanastasio@raptorengineering.com>
---
 config/ppc64.mk                          |   5 +
 xen/Makefile                             |   5 +-
 xen/arch/ppc/Kconfig                     |  42 ++++++
 xen/arch/ppc/Kconfig.debug               |   0
 xen/arch/ppc/Makefile                    |  16 +++
 xen/arch/ppc/Rules.mk                    |   0
 xen/arch/ppc/arch.mk                     |  11 ++
 xen/arch/ppc/configs/openpower_defconfig |  13 ++
 xen/arch/ppc/include/asm/config.h        |  63 +++++++++
 xen/arch/ppc/include/asm/page-bits.h     |   7 +
 xen/arch/ppc/ppc64/Makefile              |   1 +
 xen/arch/ppc/ppc64/asm-offsets.c         |   0
 xen/arch/ppc/ppc64/head.S                |  27 ++++
 xen/arch/ppc/xen.lds.S                   | 173 +++++++++++++++++++++++
 14 files changed, 361 insertions(+), 2 deletions(-)
 create mode 100644 config/ppc64.mk
 create mode 100644 xen/arch/ppc/Kconfig
 create mode 100644 xen/arch/ppc/Kconfig.debug
 create mode 100644 xen/arch/ppc/Makefile
 create mode 100644 xen/arch/ppc/Rules.mk
 create mode 100644 xen/arch/ppc/arch.mk
 create mode 100644 xen/arch/ppc/configs/openpower_defconfig
 create mode 100644 xen/arch/ppc/include/asm/config.h
 create mode 100644 xen/arch/ppc/include/asm/page-bits.h
 create mode 100644 xen/arch/ppc/ppc64/Makefile
 create mode 100644 xen/arch/ppc/ppc64/asm-offsets.c
 create mode 100644 xen/arch/ppc/ppc64/head.S
 create mode 100644 xen/arch/ppc/xen.lds.S

diff --git a/config/ppc64.mk b/config/ppc64.mk
new file mode 100644
index 0000000000..597f0668c3
--- /dev/null
+++ b/config/ppc64.mk
@@ -0,0 +1,5 @@
+CONFIG_PPC := y
+CONFIG_PPC64 := y
+CONFIG_PPC_$(XEN_OS) := y
+
+CONFIG_XEN_INSTALL_SUFFIX :=
diff --git a/xen/Makefile b/xen/Makefile
index e89fc461fc..db5454fb58 100644
--- a/xen/Makefile
+++ b/xen/Makefile
@@ -38,7 +38,7 @@ 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' \
-              -e s'/riscv.*/riscv/g')
+              -e s'/riscv.*/riscv/g' -e s'/ppc.*/ppc/g')
 export ARCH SRCARCH
 
 # Allow someone to change their config file
@@ -244,7 +244,7 @@ include $(XEN_ROOT)/Config.mk
 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' \
-                                -e s'/riscv.*/riscv/g')
+                                -e s'/riscv.*/riscv/g' -e s'/ppc.*/ppc/g')
 
 export CONFIG_SHELL := $(SHELL)
 export CC CXX LD NM OBJCOPY OBJDUMP ADDR2LINE
@@ -563,6 +563,7 @@ _clean:
 	$(Q)$(MAKE) $(clean)=xsm
 	$(Q)$(MAKE) $(clean)=crypto
 	$(Q)$(MAKE) $(clean)=arch/arm
+	$(Q)$(MAKE) $(clean)=arch/ppc
 	$(Q)$(MAKE) $(clean)=arch/riscv
 	$(Q)$(MAKE) $(clean)=arch/x86
 	$(Q)$(MAKE) $(clean)=test
diff --git a/xen/arch/ppc/Kconfig b/xen/arch/ppc/Kconfig
new file mode 100644
index 0000000000..a0a70adef4
--- /dev/null
+++ b/xen/arch/ppc/Kconfig
@@ -0,0 +1,42 @@
+config PPC
+	def_bool y
+
+config PPC64
+	def_bool y
+	select 64BIT
+
+config ARCH_DEFCONFIG
+	string
+	default "arch/ppc/configs/openpower_defconfig"
+
+menu "Architecture Features"
+
+source "arch/Kconfig"
+
+endmenu
+
+menu "ISA Selection"
+
+choice
+	prompt "Base ISA"
+	default POWER_ISA_2_07B if PPC64
+	help
+	  This selects the base ISA version that Xen will target.
+
+config POWER_ISA_2_07B
+	bool "Power ISA 2.07B"
+	help
+	  Target version 2.07B of the Power ISA (POWER8)
+
+config POWER_ISA_3_00
+	bool "Power ISA 3.00"
+	help
+	  Target version 3.00 of the Power ISA (POWER9)
+
+endchoice
+
+endmenu
+
+source "common/Kconfig"
+
+source "drivers/Kconfig"
diff --git a/xen/arch/ppc/Kconfig.debug b/xen/arch/ppc/Kconfig.debug
new file mode 100644
index 0000000000..e69de29bb2
diff --git a/xen/arch/ppc/Makefile b/xen/arch/ppc/Makefile
new file mode 100644
index 0000000000..10b101cf9c
--- /dev/null
+++ b/xen/arch/ppc/Makefile
@@ -0,0 +1,16 @@
+obj-$(CONFIG_PPC64) += ppc64/
+
+$(TARGET): $(TARGET)-syms
+	cp -f $< $@
+
+$(TARGET)-syms: $(objtree)/prelink.o $(obj)/xen.lds
+	$(LD) $(XEN_LDFLAGS) -T $(obj)/xen.lds -N $< $(build_id_linker) -o $@
+	$(NM) -pa --format=sysv $(@D)/$(@F) \
+		| $(objtree)/tools/symbols --all-symbols --xensyms --sysv --sort \
+		>$(@D)/$(@F).map
+
+$(obj)/xen.lds: $(src)/xen.lds.S FORCE
+	$(call if_changed_dep,cpp_lds_S)
+
+.PHONY: include
+include:
diff --git a/xen/arch/ppc/Rules.mk b/xen/arch/ppc/Rules.mk
new file mode 100644
index 0000000000..e69de29bb2
diff --git a/xen/arch/ppc/arch.mk b/xen/arch/ppc/arch.mk
new file mode 100644
index 0000000000..c185a5028a
--- /dev/null
+++ b/xen/arch/ppc/arch.mk
@@ -0,0 +1,11 @@
+########################################
+# Power-specific definitions
+
+ppc-march-$(CONFIG_POWER_ISA_2_07B) := power8
+ppc-march-$(CONFIG_POWER_ISA_3_00) := power9
+
+CFLAGS += -mcpu=$(ppc-march-y) -mstrict-align -mcmodel=large -mabi=elfv2 -mno-altivec -mno-vsx
+
+# TODO: Drop override when more of the build is working
+override ALL_OBJS-y = arch/$(TARGET_ARCH)/built_in.o
+override ALL_LIBS-y =
diff --git a/xen/arch/ppc/configs/openpower_defconfig b/xen/arch/ppc/configs/openpower_defconfig
new file mode 100644
index 0000000000..8783eb3488
--- /dev/null
+++ b/xen/arch/ppc/configs/openpower_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_PPC64=y
+CONFIG_DEBUG=y
+CONFIG_DEBUG_INFO=y
+CONFIG_EXPERT=y
diff --git a/xen/arch/ppc/include/asm/config.h b/xen/arch/ppc/include/asm/config.h
new file mode 100644
index 0000000000..7a2862ef7a
--- /dev/null
+++ b/xen/arch/ppc/include/asm/config.h
@@ -0,0 +1,63 @@
+#ifndef __PPC_CONFIG_H__
+#define __PPC_CONFIG_H__
+
+#include <xen/const.h>
+#include <xen/page-size.h>
+
+#if defined(CONFIG_PPC64)
+#define LONG_BYTEORDER 3
+#define ELFSIZE        64
+#define MAX_VIRT_CPUS  1024u
+#else
+#error "Unsupported PowerPC 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_PPC_L1_CACHE_SHIFT  7
+#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 PPC */
+#ifdef __ASSEMBLY__
+#define ALIGN .align 2
+
+#define ENTRY(name)                                                            \
+    .globl name;                                                               \
+    ALIGN;                                                                     \
+    name:
+#endif
+
+#define XEN_VIRT_START _AT(UL, 0x400000)
+
+#define SMP_CACHE_BYTES (1 << 6)
+
+#define STACK_ORDER 2
+#define STACK_SIZE  (PAGE_SIZE << STACK_ORDER)
+
+/* 288 bytes below the stack pointer must be preserved by interrupt handlers */
+#define STACK_VOLATILE_AREA 288
+
+/* size of minimum stack frame; C code can write into the caller's stack */
+#define STACK_FRAME_OVERHEAD 32
+
+#endif /* __PPC_CONFIG_H__ */
+/*
+ * Local variables:
+ * mode: C
+ * c-file-style: "BSD"
+ * c-basic-offset: 4
+ * indent-tabs-mode: nil
+ * End:
+ */
diff --git a/xen/arch/ppc/include/asm/page-bits.h b/xen/arch/ppc/include/asm/page-bits.h
new file mode 100644
index 0000000000..4c01bf9716
--- /dev/null
+++ b/xen/arch/ppc/include/asm/page-bits.h
@@ -0,0 +1,7 @@
+#ifndef __PPC_PAGE_BITS_H__
+#define __PPC_PAGE_BITS_H__
+
+#define PAGE_SHIFT              16 /* 64 KiB Pages */
+#define PADDR_BITS              48
+
+#endif /* __PPC_PAGE_BITS_H__ */
diff --git a/xen/arch/ppc/ppc64/Makefile b/xen/arch/ppc/ppc64/Makefile
new file mode 100644
index 0000000000..3340058c08
--- /dev/null
+++ b/xen/arch/ppc/ppc64/Makefile
@@ -0,0 +1 @@
+obj-y += head.o
diff --git a/xen/arch/ppc/ppc64/asm-offsets.c b/xen/arch/ppc/ppc64/asm-offsets.c
new file mode 100644
index 0000000000..e69de29bb2
diff --git a/xen/arch/ppc/ppc64/head.S b/xen/arch/ppc/ppc64/head.S
new file mode 100644
index 0000000000..e24331f95c
--- /dev/null
+++ b/xen/arch/ppc/ppc64/head.S
@@ -0,0 +1,27 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+.section .text.header, "ax", %progbits
+
+ENTRY(start)
+    /*
+     * Depending on how we were booted, the CPU could be running in either
+     * Little Endian or Big Endian mode. The following trampoline from Linux
+     * cleverly uses an instruction that encodes to a NOP if the CPU's
+     * endianness matches the assumption of the assembler (LE, in our case)
+     * or a branch to code that performs the endian switch in the other case.
+     */
+    tdi 0, 0, 0x48    /* Reverse endian of b . + 8          */
+    b $ + 44          /* Skip trampoline if endian is good  */
+    .long 0xa600607d  /* mfmsr r11                          */
+    .long 0x01006b69  /* xori r11,r11,1                     */
+    .long 0x00004039  /* li r10,0                           */
+    .long 0x6401417d  /* mtmsrd r10,1                       */
+    .long 0x05009f42  /* bcl 20,31,$+4                      */
+    .long 0xa602487d  /* mflr r10                           */
+    .long 0x14004a39  /* addi r10,r10,20                    */
+    .long 0xa6035a7d  /* mtsrr0 r10                         */
+    .long 0xa6037b7d  /* mtsrr1 r11                         */
+    .long 0x2400004c  /* rfid                               */
+
+    /* Now that the endianness is confirmed, continue */
+1:  b 1b
diff --git a/xen/arch/ppc/xen.lds.S b/xen/arch/ppc/xen.lds.S
new file mode 100644
index 0000000000..89fcdc9c00
--- /dev/null
+++ b/xen/arch/ppc/xen.lds.S
@@ -0,0 +1,173 @@
+#include <xen/xen.lds.h>
+
+#undef ENTRY
+#undef ALIGN
+
+OUTPUT_ARCH(powerpc:common64)
+ENTRY(start)
+
+PHDRS
+{
+    text PT_LOAD ;
+#if defined(BUILD_ID)
+    note PT_NOTE ;
+#endif
+}
+
+/**
+ * OF's base load address is 0x400000 (XEN_VIRT_START).
+ * By defining sections this way, we can keep our virtual address base at 0x400000
+ * while keeping the physical base at 0x0.
+ *
+ * Without this, OF incorrectly loads .text at 0x400000 + 0x400000 = 0x800000.
+ * Taken from x86/xen.lds.S
+ */
+#ifdef CONFIG_LD_IS_GNU
+# define DECL_SECTION(x) x : AT(ADDR(#x) - XEN_VIRT_START)
+#else
+# define DECL_SECTION(x) x : AT(ADDR(x) - XEN_VIRT_START)
+#endif
+
+SECTIONS
+{
+    . = XEN_VIRT_START;
+
+    DECL_SECTION(.text) {
+        _stext = .;            /* Text section */
+        *(.text.header)
+
+        *(.text.cold)
+        *(.text.unlikely .text.*_unlikely .text.unlikely.*)
+
+        *(.text)
+#ifdef CONFIG_CC_SPLIT_SECTIONS
+        *(.text.*)
+#endif
+
+        *(.fixup)
+        *(.gnu.warning)
+        . = ALIGN(POINTER_ALIGN);
+        _etext = .;             /* End of text section */
+    } :text
+
+    . = ALIGN(PAGE_SIZE);
+    DECL_SECTION(.rodata) {
+        _srodata = .;          /* Read-only data */
+        *(.rodata)
+        *(.rodata.*)
+        *(.data.rel.ro)
+        *(.data.rel.ro.*)
+
+        VPCI_ARRAY
+
+        . = ALIGN(POINTER_ALIGN);
+        _erodata = .;        /* End of read-only data */
+    } :text
+
+    #if defined(BUILD_ID)
+    . = ALIGN(4);
+    DECL_SECTION(.note.gnu.build-id) {
+        __note_gnu_build_id_start = .;
+        *(.note.gnu.build-id)
+        __note_gnu_build_id_end = .;
+    } :note :text
+    #endif
+    _erodata = .;                /* End of read-only data */
+
+    . = ALIGN(PAGE_SIZE);
+    DECL_SECTION(.data.ro_after_init) {
+        __ro_after_init_start = .;
+        *(.data.ro_after_init)
+        . = ALIGN(PAGE_SIZE);
+        __ro_after_init_end = .;
+    } : text
+
+    DECL_SECTION(.data.read_mostly) {
+        *(.data.read_mostly)
+    } :text
+
+    . = ALIGN(PAGE_SIZE);
+    DECL_SECTION(.data) {                    /* Data */
+        *(.data.page_aligned)
+        . = ALIGN(8);
+        __start_schedulers_array = .;
+        *(.data.schedulers)
+        __end_schedulers_array = .;
+
+        HYPFS_PARAM
+
+        *(.data .data.*)
+        CONSTRUCTORS
+    } :text
+
+    . = ALIGN(PAGE_SIZE);             /* Init code and data */
+    __init_begin = .;
+    DECL_SECTION(.init.text) {
+        _sinittext = .;
+        *(.init.text)
+        _einittext = .;
+        . = ALIGN(PAGE_SIZE);        /* Avoid mapping alt insns executable */
+    } :text
+
+    . = ALIGN(PAGE_SIZE);
+    DECL_SECTION(.init.data) {
+        *(.init.rodata)
+        *(.init.rodata.*)
+
+        . = ALIGN(POINTER_ALIGN);
+        __setup_start = .;
+        *(.init.setup)
+        __setup_end = .;
+
+        __initcall_start = .;
+        *(.initcallpresmp.init)
+        __presmp_initcall_end = .;
+        *(.initcall1.init)
+        __initcall_end = .;
+
+        LOCK_PROFILE_DATA
+
+        *(.init.data)
+        *(.init.data.rel)
+        *(.init.data.rel.*)
+
+        . = ALIGN(8);
+        __ctors_start = .;
+        *(.ctors)
+        *(.init_array)
+        *(SORT(.init_array.*))
+        __ctors_end = .;
+    } :text
+    . = ALIGN(POINTER_ALIGN);
+    __init_end = .;
+
+    DECL_SECTION(.bss) {                     /* BSS */
+        __bss_start = .;
+        *(.bss.stack_aligned)
+        . = ALIGN(PAGE_SIZE);
+        *(.bss.page_aligned)
+        . = ALIGN(PAGE_SIZE);
+        __per_cpu_start = .;
+        *(.bss.percpu.page_aligned)
+        *(.bss.percpu)
+        . = ALIGN(SMP_CACHE_BYTES);
+        *(.bss.percpu.read_mostly)
+        . = ALIGN(SMP_CACHE_BYTES);
+        __per_cpu_data_end = .;
+        *(.bss .bss.*)
+        . = ALIGN(POINTER_ALIGN);
+        __bss_end = .;
+    } :text
+    _end = . ;
+
+    /* Section for the device tree blob (if any). */
+    DECL_SECTION(.dtb) { *(.dtb) } :text
+
+    DWARF2_DEBUG_SECTIONS
+
+    DISCARD_SECTIONS
+
+    STABS_DEBUG_SECTIONS
+
+    ELF_DETAILS_SECTIONS
+}
-- 
2.30.2



^ permalink raw reply related	[flat|nested] 11+ messages in thread
* [PATCH v3 3/4] automation: Add ppc64le cross-build jobs
  2023-06-13 14:49 [PATCH v3 0/4] Initial support for Power Shawn Anastasio
  2023-06-13 14:49 ` [PATCH v3 1/4] automation: Add container for ppc64le builds Shawn Anastasio
  2023-06-13 14:50 ` [PATCH v3 2/4] xen: Add files needed for minimal ppc64le build Shawn Anastasio
@ 2023-06-13 14:50 ` Shawn Anastasio
  2023-06-13 14:50 ` [PATCH v3 4/4] maintainers: Add ppc64 maintainer Shawn Anastasio
  3 siblings, 0 replies; 11+ messages in thread
From: Shawn Anastasio @ 2023-06-13 14:50 UTC (permalink / raw)
  To: xen-devel
  Cc: tpearson, Shawn Anastasio, Doug Goldstein, Stefano Stabellini,
	Shawn Anastasio

Add build jobs to cross-compile Xen for ppc64le.

Signed-off-by: Shawn Anastasio <sanastasio@raptorengineering.com>
---
 automation/gitlab-ci/build.yaml | 60 +++++++++++++++++++++++++++++++++
 1 file changed, 60 insertions(+)

diff --git a/automation/gitlab-ci/build.yaml b/automation/gitlab-ci/build.yaml
index 420ffa5acb..bd8c7332db 100644
--- a/automation/gitlab-ci/build.yaml
+++ b/automation/gitlab-ci/build.yaml
@@ -183,6 +183,33 @@
   variables:
     <<: *gcc
 
+.ppc64le-cross-build-tmpl:
+  <<: *build
+  variables:
+    XEN_TARGET_ARCH: ppc64
+  tags:
+    - x86_64
+
+.ppc64le-cross-build:
+  extends: .ppc64le-cross-build-tmpl
+  variables:
+    debug: n
+
+.ppc64le-cross-build-debug:
+  extends: .ppc64le-cross-build-tmpl
+  variables:
+    debug: y
+
+.gcc-ppc64le-cross-build:
+  extends: .ppc64le-cross-build
+  variables:
+    <<: *gcc
+
+.gcc-ppc64le-cross-build-debug:
+  extends: .ppc64le-cross-build-debug
+  variables:
+    <<: *gcc
+
 .yocto-test:
   stage: build
   image: registry.gitlab.com/xen-project/xen/${CONTAINER}
@@ -516,6 +543,39 @@ archlinux-current-gcc-riscv64-debug-randconfig:
     EXTRA_FIXED_RANDCONFIG:
       CONFIG_COVERAGE=n
 
+# Power cross-build
+debian-bullseye-gcc-ppc64le:
+  extends: .gcc-ppc64le-cross-build
+  variables:
+    CONTAINER: debian:bullseye-ppc64le
+    KBUILD_DEFCONFIG: openpower_defconfig
+    HYPERVISOR_ONLY: y
+
+debian-bullseye-gcc-ppc64le-debug:
+  extends: .gcc-ppc64le-cross-build-debug
+  variables:
+    CONTAINER: debian:bullseye-ppc64le
+    KBUILD_DEFCONFIG: openpower_defconfig
+    HYPERVISOR_ONLY: y
+
+debian-bullseye-gcc-ppc64le-randconfig:
+  extends: .gcc-ppc64le-cross-build
+  variables:
+    CONTAINER: debian:bullseye-ppc64le
+    KBUILD_DEFCONFIG: openpower_defconfig
+    RANDCONFIG: y
+    EXTRA_FIXED_RANDCONFIG:
+      CONFIG_COVERAGE=n
+
+debian-bullseye-gcc-ppc64le-debug-randconfig:
+  extends: .gcc-ppc64le-cross-build-debug
+  variables:
+    CONTAINER: debian:bullseye-ppc64le
+    KBUILD_DEFCONFIG: openpower_defconfig
+    RANDCONFIG: y
+    EXTRA_FIXED_RANDCONFIG:
+      CONFIG_COVERAGE=n
+
 # Yocto test jobs
 yocto-qemuarm64:
   extends: .yocto-test-arm64
-- 
2.30.2



^ permalink raw reply related	[flat|nested] 11+ messages in thread
* [PATCH v3 4/4] maintainers: Add ppc64 maintainer
  2023-06-13 14:49 [PATCH v3 0/4] Initial support for Power Shawn Anastasio
                   ` (2 preceding siblings ...)
  2023-06-13 14:50 ` [PATCH v3 3/4] automation: Add ppc64le cross-build jobs Shawn Anastasio
@ 2023-06-13 14:50 ` Shawn Anastasio
  3 siblings, 0 replies; 11+ messages in thread
From: Shawn Anastasio @ 2023-06-13 14:50 UTC (permalink / raw)
  To: xen-devel
  Cc: tpearson, Shawn Anastasio, Andrew Cooper, George Dunlap,
	Jan Beulich, Julien Grall, Stefano Stabellini, Wei Liu,
	Shawn Anastasio

Signed-off-by: Shawn Anastasio <sanastasio@raptorengineering.com>
---
 MAINTAINERS | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/MAINTAINERS b/MAINTAINERS
index 1bb7a6a839..25139fe4a3 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -460,6 +460,10 @@ X:	xen/arch/x86/acpi/lib.c
 F:	xen/drivers/cpufreq/
 F:	xen/include/acpi/cpufreq/
 
+PPC64
+M:	Shawn Anastasio <sanastasio@raptorengineering.com>
+F:	xen/arch/ppc/
+
 PUBLIC I/O INTERFACES AND PV DRIVERS DESIGNS
 M:	Juergen Gross <jgross@suse.com>
 S:	Supported
-- 
2.30.2



^ permalink raw reply related	[flat|nested] 11+ messages in thread
* Re: [PATCH v3 2/4] xen: Add files needed for minimal ppc64le build
  2023-06-13 14:50 ` [PATCH v3 2/4] xen: Add files needed for minimal ppc64le build Shawn Anastasio
@ 2023-06-14 15:51   ` Jan Beulich
  2023-06-14 16:36     ` Shawn Anastasio
  0 siblings, 1 reply; 11+ messages in thread
From: Jan Beulich @ 2023-06-14 15:51 UTC (permalink / raw)
  To: Shawn Anastasio
  Cc: tpearson, Andrew Cooper, George Dunlap, Julien Grall,
	Stefano Stabellini, Wei Liu, Shawn Anastasio, xen-devel

On 13.06.2023 16:50, Shawn Anastasio wrote:
> --- /dev/null
> +++ b/xen/arch/ppc/Makefile
> @@ -0,0 +1,16 @@
> +obj-$(CONFIG_PPC64) += ppc64/
> +
> +$(TARGET): $(TARGET)-syms
> +	cp -f $< $@
> +
> +$(TARGET)-syms: $(objtree)/prelink.o $(obj)/xen.lds
> +	$(LD) $(XEN_LDFLAGS) -T $(obj)/xen.lds -N $< $(build_id_linker) -o $@
> +	$(NM) -pa --format=sysv $(@D)/$(@F) \
> +		| $(objtree)/tools/symbols --all-symbols --xensyms --sysv --sort \
> +		>$(@D)/$(@F).map

Elsewhere we recently switched these uses of $(@D)/$(@F) to just $@.
Please can you do so here as well?

> --- /dev/null
> +++ b/xen/arch/ppc/arch.mk
> @@ -0,0 +1,11 @@
> +########################################
> +# Power-specific definitions
> +
> +ppc-march-$(CONFIG_POWER_ISA_2_07B) := power8
> +ppc-march-$(CONFIG_POWER_ISA_3_00) := power9
> +
> +CFLAGS += -mcpu=$(ppc-march-y) -mstrict-align -mcmodel=large -mabi=elfv2 -mno-altivec -mno-vsx

Wouldn't it make sense to also pass -mlittle here, such that a tool
chain defaulting to big-endian can still be used?

> --- /dev/null
> +++ b/xen/arch/ppc/ppc64/head.S
> @@ -0,0 +1,27 @@
> +/* SPDX-License-Identifier: GPL-2.0-or-later */
> +
> +.section .text.header, "ax", %progbits
> +
> +ENTRY(start)
> +    /*
> +     * Depending on how we were booted, the CPU could be running in either
> +     * Little Endian or Big Endian mode. The following trampoline from Linux
> +     * cleverly uses an instruction that encodes to a NOP if the CPU's
> +     * endianness matches the assumption of the assembler (LE, in our case)
> +     * or a branch to code that performs the endian switch in the other case.
> +     */
> +    tdi 0, 0, 0x48    /* Reverse endian of b . + 8          */
> +    b $ + 44          /* Skip trampoline if endian is good  */

If I get this right, $ and . are interchangable on Power? If not,
then all is fine and there likely is a reason to use . in the
comment but $ in the code. But if so, it would be nice if both
could match, and I guess with other architectures in mind . would
be preferable.

> --- /dev/null
> +++ b/xen/arch/ppc/xen.lds.S
> @@ -0,0 +1,173 @@
> +#include <xen/xen.lds.h>
> +
> +#undef ENTRY
> +#undef ALIGN
> +
> +OUTPUT_ARCH(powerpc:common64)
> +ENTRY(start)
> +
> +PHDRS
> +{
> +    text PT_LOAD ;
> +#if defined(BUILD_ID)
> +    note PT_NOTE ;
> +#endif
> +}
> +
> +/**
> + * OF's base load address is 0x400000 (XEN_VIRT_START).
> + * By defining sections this way, we can keep our virtual address base at 0x400000
> + * while keeping the physical base at 0x0.
> + *
> + * Without this, OF incorrectly loads .text at 0x400000 + 0x400000 = 0x800000.
> + * Taken from x86/xen.lds.S
> + */
> +#ifdef CONFIG_LD_IS_GNU
> +# define DECL_SECTION(x) x : AT(ADDR(#x) - XEN_VIRT_START)
> +#else
> +# define DECL_SECTION(x) x : AT(ADDR(x) - XEN_VIRT_START)
> +#endif
> +
> +SECTIONS
> +{
> +    . = XEN_VIRT_START;
> +
> +    DECL_SECTION(.text) {
> +        _stext = .;            /* Text section */
> +        *(.text.header)
> +
> +        *(.text.cold)
> +        *(.text.unlikely .text.*_unlikely .text.unlikely.*)
> +
> +        *(.text)
> +#ifdef CONFIG_CC_SPLIT_SECTIONS
> +        *(.text.*)
> +#endif
> +
> +        *(.fixup)
> +        *(.gnu.warning)
> +        . = ALIGN(POINTER_ALIGN);
> +        _etext = .;             /* End of text section */
> +    } :text
> +
> +    . = ALIGN(PAGE_SIZE);
> +    DECL_SECTION(.rodata) {
> +        _srodata = .;          /* Read-only data */
> +        *(.rodata)
> +        *(.rodata.*)
> +        *(.data.rel.ro)
> +        *(.data.rel.ro.*)
> +
> +        VPCI_ARRAY
> +
> +        . = ALIGN(POINTER_ALIGN);
> +        _erodata = .;        /* End of read-only data */
> +    } :text
> +
> +    #if defined(BUILD_ID)
> +    . = ALIGN(4);
> +    DECL_SECTION(.note.gnu.build-id) {
> +        __note_gnu_build_id_start = .;
> +        *(.note.gnu.build-id)
> +        __note_gnu_build_id_end = .;
> +    } :note :text
> +    #endif
> +    _erodata = .;                /* End of read-only data */
> +
> +    . = ALIGN(PAGE_SIZE);
> +    DECL_SECTION(.data.ro_after_init) {
> +        __ro_after_init_start = .;
> +        *(.data.ro_after_init)
> +        . = ALIGN(PAGE_SIZE);
> +        __ro_after_init_end = .;
> +    } : text
> +
> +    DECL_SECTION(.data.read_mostly) {
> +        *(.data.read_mostly)
> +    } :text
> +
> +    . = ALIGN(PAGE_SIZE);
> +    DECL_SECTION(.data) {                    /* Data */
> +        *(.data.page_aligned)
> +        . = ALIGN(8);
> +        __start_schedulers_array = .;
> +        *(.data.schedulers)
> +        __end_schedulers_array = .;
> +
> +        HYPFS_PARAM
> +
> +        *(.data .data.*)
> +        CONSTRUCTORS
> +    } :text
> +
> +    . = ALIGN(PAGE_SIZE);             /* Init code and data */
> +    __init_begin = .;
> +    DECL_SECTION(.init.text) {
> +        _sinittext = .;
> +        *(.init.text)
> +        _einittext = .;
> +        . = ALIGN(PAGE_SIZE);        /* Avoid mapping alt insns executable */
> +    } :text
> +
> +    . = ALIGN(PAGE_SIZE);
> +    DECL_SECTION(.init.data) {
> +        *(.init.rodata)
> +        *(.init.rodata.*)
> +
> +        . = ALIGN(POINTER_ALIGN);
> +        __setup_start = .;
> +        *(.init.setup)
> +        __setup_end = .;
> +
> +        __initcall_start = .;
> +        *(.initcallpresmp.init)
> +        __presmp_initcall_end = .;
> +        *(.initcall1.init)
> +        __initcall_end = .;
> +
> +        LOCK_PROFILE_DATA
> +
> +        *(.init.data)
> +        *(.init.data.rel)
> +        *(.init.data.rel.*)
> +
> +        . = ALIGN(8);
> +        __ctors_start = .;
> +        *(.ctors)
> +        *(.init_array)
> +        *(SORT(.init_array.*))
> +        __ctors_end = .;
> +    } :text
> +    . = ALIGN(POINTER_ALIGN);
> +    __init_end = .;

Up to here I think I agree with all uses of ALIGN(), but ...

> +    DECL_SECTION(.bss) {                     /* BSS */
> +        __bss_start = .;
> +        *(.bss.stack_aligned)
> +        . = ALIGN(PAGE_SIZE);
> +        *(.bss.page_aligned)

... the one between the two .bss parts looks unmotivated. Within
a section definition ALIGN() typically only makes sense when followed
by a label definition, like ...

> +        . = ALIGN(PAGE_SIZE);
> +        __per_cpu_start = .;

... here.

> +        *(.bss.percpu.page_aligned)
> +        *(.bss.percpu)
> +        . = ALIGN(SMP_CACHE_BYTES);

This one is an exception, as it is intended to separate the read-mostly
part such that there's no shared cache line.

Jan

> +        *(.bss.percpu.read_mostly)
> +        . = ALIGN(SMP_CACHE_BYTES);
> +        __per_cpu_data_end = .;
> +        *(.bss .bss.*)
> +        . = ALIGN(POINTER_ALIGN);
> +        __bss_end = .;
> +    } :text
> +    _end = . ;
> +
> +    /* Section for the device tree blob (if any). */
> +    DECL_SECTION(.dtb) { *(.dtb) } :text
> +
> +    DWARF2_DEBUG_SECTIONS
> +
> +    DISCARD_SECTIONS
> +
> +    STABS_DEBUG_SECTIONS
> +
> +    ELF_DETAILS_SECTIONS
> +}



^ permalink raw reply	[flat|nested] 11+ messages in thread
* Re: [PATCH v3 2/4] xen: Add files needed for minimal ppc64le build
  2023-06-14 15:51   ` Jan Beulich
@ 2023-06-14 16:36     ` Shawn Anastasio
  2023-06-15  6:47       ` Jan Beulich
  2023-07-05  6:44       ` Jan Beulich
  0 siblings, 2 replies; 11+ messages in thread
From: Shawn Anastasio @ 2023-06-14 16:36 UTC (permalink / raw)
  To: Jan Beulich
  Cc: tpearson, Andrew Cooper, George Dunlap, Julien Grall,
	Stefano Stabellini, Wei Liu, Shawn Anastasio, xen-devel

On Wed Jun 14, 2023 at 10:51 AM CDT, Jan Beulich wrote:
> On 13.06.2023 16:50, Shawn Anastasio wrote:
> > --- /dev/null
> > +++ b/xen/arch/ppc/Makefile
> > @@ -0,0 +1,16 @@
> > +obj-$(CONFIG_PPC64) += ppc64/
> > +
> > +$(TARGET): $(TARGET)-syms
> > +	cp -f $< $@
> > +
> > +$(TARGET)-syms: $(objtree)/prelink.o $(obj)/xen.lds
> > +	$(LD) $(XEN_LDFLAGS) -T $(obj)/xen.lds -N $< $(build_id_linker) -o $@
> > +	$(NM) -pa --format=sysv $(@D)/$(@F) \
> > +		| $(objtree)/tools/symbols --all-symbols --xensyms --sysv --sort \
> > +		>$(@D)/$(@F).map
>
> Elsewhere we recently switched these uses of $(@D)/$(@F) to just $@.
> Please can you do so here as well?

Sure, will fix in v4.

> > --- /dev/null
> > +++ b/xen/arch/ppc/arch.mk
> > @@ -0,0 +1,11 @@
> > +########################################
> > +# Power-specific definitions
> > +
> > +ppc-march-$(CONFIG_POWER_ISA_2_07B) := power8
> > +ppc-march-$(CONFIG_POWER_ISA_3_00) := power9
> > +
> > +CFLAGS += -mcpu=$(ppc-march-y) -mstrict-align -mcmodel=large -mabi=elfv2 -mno-altivec -mno-vsx
>
> Wouldn't it make sense to also pass -mlittle here, such that a tool
> chain defaulting to big-endian can still be used?

Good call. On this topic, I suppose I'll also add -m64 to allow 32-bit
toolchains to be used as well.

> > --- /dev/null
> > +++ b/xen/arch/ppc/ppc64/head.S
> > @@ -0,0 +1,27 @@
> > +/* SPDX-License-Identifier: GPL-2.0-or-later */
> > +
> > +.section .text.header, "ax", %progbits
> > +
> > +ENTRY(start)
> > +    /*
> > +     * Depending on how we were booted, the CPU could be running in either
> > +     * Little Endian or Big Endian mode. The following trampoline from Linux
> > +     * cleverly uses an instruction that encodes to a NOP if the CPU's
> > +     * endianness matches the assumption of the assembler (LE, in our case)
> > +     * or a branch to code that performs the endian switch in the other case.
> > +     */
> > +    tdi 0, 0, 0x48    /* Reverse endian of b . + 8          */
> > +    b $ + 44          /* Skip trampoline if endian is good  */
>
> If I get this right, $ and . are interchangable on Power? If not,
> then all is fine and there likely is a reason to use . in the
> comment but $ in the code. But if so, it would be nice if both
> could match, and I guess with other architectures in mind . would
> be preferable.

As hinted by the comment, this code was directly inherited from Linux
and I'm not sure why the original author chose '$' instead of '.'. That
said, as far as I can tell you are correct about the two being
interchangeable, and changing the $ to . results in the exact same
machine code.

I can go ahead and make the change for consistency in v4.

> > +    DECL_SECTION(.bss) {                     /* BSS */
> > +        __bss_start = .;
> > +        *(.bss.stack_aligned)
> > +        . = ALIGN(PAGE_SIZE);
> > +        *(.bss.page_aligned)
>
> ... the one between the two .bss parts looks unmotivated. Within
> a section definition ALIGN() typically only makes sense when followed
> by a label definition, like ...

Correct me if I'm wrong, but wouldn't the ALIGN here serve to ensure
that the subsequent '.bss.page_aligned' section has the correct alignment
that its name implies?

> Jan

Thanks,
Shawn


^ permalink raw reply	[flat|nested] 11+ messages in thread
* Re: [PATCH v3 2/4] xen: Add files needed for minimal ppc64le build
  2023-06-14 16:36     ` Shawn Anastasio
@ 2023-06-15  6:47       ` Jan Beulich
  2023-06-16 17:00         ` Shawn Anastasio
  2023-07-05  6:44       ` Jan Beulich
  1 sibling, 1 reply; 11+ messages in thread
From: Jan Beulich @ 2023-06-15  6:47 UTC (permalink / raw)
  To: Shawn Anastasio
  Cc: tpearson, Andrew Cooper, George Dunlap, Julien Grall,
	Stefano Stabellini, Wei Liu, Shawn Anastasio, xen-devel

On 14.06.2023 18:36, Shawn Anastasio wrote:
> On Wed Jun 14, 2023 at 10:51 AM CDT, Jan Beulich wrote:
>> On 13.06.2023 16:50, Shawn Anastasio wrote:
>>> +    DECL_SECTION(.bss) {                     /* BSS */
>>> +        __bss_start = .;
>>> +        *(.bss.stack_aligned)
>>> +        . = ALIGN(PAGE_SIZE);
>>> +        *(.bss.page_aligned)
>>
>> ... the one between the two .bss parts looks unmotivated. Within
>> a section definition ALIGN() typically only makes sense when followed
>> by a label definition, like ...
> 
> Correct me if I'm wrong, but wouldn't the ALIGN here serve to ensure
> that the subsequent '.bss.page_aligned' section has the correct alignment
> that its name implies?

Yes and no. Thing is that every contribution to .bss.page_aligned already
needs to specify page alignment itself, or else it may break if any earlier
contribution was page-aligned, but not a full page in size (which I think
the compiler wouldn't allow to happen, but assembly code can result in
such). Note how this very ALIGN() was recently dropped from RISC-V code,
and my respective Arm side patch is also about to go in.

Jan


^ permalink raw reply	[flat|nested] 11+ messages in thread
* Re: [PATCH v3 1/4] automation: Add container for ppc64le builds
  2023-06-13 14:49 ` [PATCH v3 1/4] automation: Add container for ppc64le builds Shawn Anastasio
@ 2023-06-16 15:29   ` Andrew Cooper
  0 siblings, 0 replies; 11+ messages in thread
From: Andrew Cooper @ 2023-06-16 15:29 UTC (permalink / raw)
  To: Shawn Anastasio, xen-devel
  Cc: tpearson, Doug Goldstein, Stefano Stabellini, Shawn Anastasio

On 13/06/2023 3:49 pm, Shawn Anastasio wrote:
> Add a container for cross-compiling xen for ppc64le.
>
> Signed-off-by: Shawn Anastasio <sanastasio@raptorengineering.com>

Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>

I've built and deployed this container properly, replacing the prototype
from earlier.


^ permalink raw reply	[flat|nested] 11+ messages in thread
* Re: [PATCH v3 2/4] xen: Add files needed for minimal ppc64le build
  2023-06-15  6:47       ` Jan Beulich
@ 2023-06-16 17:00         ` Shawn Anastasio
  0 siblings, 0 replies; 11+ messages in thread
From: Shawn Anastasio @ 2023-06-16 17:00 UTC (permalink / raw)
  To: Jan Beulich
  Cc: tpearson, Andrew Cooper, George Dunlap, Julien Grall,
	Stefano Stabellini, Wei Liu, Shawn Anastasio, xen-devel

On Thu Jun 15, 2023 at 1:47 AM CDT, Jan Beulich wrote:
> On 14.06.2023 18:36, Shawn Anastasio wrote:
> > On Wed Jun 14, 2023 at 10:51 AM CDT, Jan Beulich wrote:
> >> On 13.06.2023 16:50, Shawn Anastasio wrote:
> >>> +    DECL_SECTION(.bss) {                     /* BSS */
> >>> +        __bss_start = .;
> >>> +        *(.bss.stack_aligned)
> >>> +        . = ALIGN(PAGE_SIZE);
> >>> +        *(.bss.page_aligned)
> >>
> >> ... the one between the two .bss parts looks unmotivated. Within
> >> a section definition ALIGN() typically only makes sense when followed
> >> by a label definition, like ...
> > 
> > Correct me if I'm wrong, but wouldn't the ALIGN here serve to ensure
> > that the subsequent '.bss.page_aligned' section has the correct alignment
> > that its name implies?
>
> Yes and no. Thing is that every contribution to .bss.page_aligned already
> needs to specify page alignment itself, or else it may break if any earlier
> contribution was page-aligned, but not a full page in size (which I think
> the compiler wouldn't allow to happen, but assembly code can result in
> such). Note how this very ALIGN() was recently dropped from RISC-V code,
> and my respective Arm side patch is also about to go in.

That makes sense, thanks. I'll get rid of the ALIGN here in v4.

> Jan

Thanks,
Shawn



^ permalink raw reply	[flat|nested] 11+ messages in thread
* Re: [PATCH v3 2/4] xen: Add files needed for minimal ppc64le build
  2023-06-14 16:36     ` Shawn Anastasio
  2023-06-15  6:47       ` Jan Beulich
@ 2023-07-05  6:44       ` Jan Beulich
  1 sibling, 0 replies; 11+ messages in thread
From: Jan Beulich @ 2023-07-05  6:44 UTC (permalink / raw)
  To: Shawn Anastasio
  Cc: tpearson, Andrew Cooper, George Dunlap, Julien Grall,
	Stefano Stabellini, Wei Liu, Shawn Anastasio, xen-devel

On 14.06.2023 18:36, Shawn Anastasio wrote:
> On Wed Jun 14, 2023 at 10:51 AM CDT, Jan Beulich wrote:
>> On 13.06.2023 16:50, Shawn Anastasio wrote:
>>> --- /dev/null
>>> +++ b/xen/arch/ppc/arch.mk
>>> @@ -0,0 +1,11 @@
>>> +########################################
>>> +# Power-specific definitions
>>> +
>>> +ppc-march-$(CONFIG_POWER_ISA_2_07B) := power8
>>> +ppc-march-$(CONFIG_POWER_ISA_3_00) := power9
>>> +
>>> +CFLAGS += -mcpu=$(ppc-march-y) -mstrict-align -mcmodel=large -mabi=elfv2 -mno-altivec -mno-vsx
>>
>> Wouldn't it make sense to also pass -mlittle here, such that a tool
>> chain defaulting to big-endian can still be used?
> 
> Good call. On this topic, I suppose I'll also add -m64 to allow 32-bit
> toolchains to be used as well.

Turns out this isn't quite enough. When trying to test my little bit of
re-basing of Anthony's series, I ran into ld complaining about little
endian input when the target format is big endian (like for the compiler
I'm using a default configured, i.e. big-endian, binutils build). Looks
like we need to pass "-m elf64lppc" to the linker; I'll see if that
helps (and where exactly to put it).

Jan


^ permalink raw reply	[flat|nested] 11+ messages in thread
end of thread, other threads:[~2023-07-05  6:45 UTC | newest]

Thread overview: 11+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2023-06-13 14:49 [PATCH v3 0/4] Initial support for Power Shawn Anastasio
2023-06-13 14:49 ` [PATCH v3 1/4] automation: Add container for ppc64le builds Shawn Anastasio
2023-06-16 15:29   ` Andrew Cooper
2023-06-13 14:50 ` [PATCH v3 2/4] xen: Add files needed for minimal ppc64le build Shawn Anastasio
2023-06-14 15:51   ` Jan Beulich
2023-06-14 16:36     ` Shawn Anastasio
2023-06-15  6:47       ` Jan Beulich
2023-06-16 17:00         ` Shawn Anastasio
2023-07-05  6:44       ` Jan Beulich
2023-06-13 14:50 ` [PATCH v3 3/4] automation: Add ppc64le cross-build jobs Shawn Anastasio
2023-06-13 14:50 ` [PATCH v3 4/4] maintainers: Add ppc64 maintainer Shawn Anastasio

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