[PATCH v5 33/36] Hexagon: Add configuration and makefiles for the Hexagon architecture.

[PATCH v5 33/36] Hexagon: Add configuration and makefiles for the Hexagon architecture.

[Richard Kuo]

Signed-off-by: Linas Vepstas <linas@codeaurora.org>
Signed-off-by: Richard Kuo <rkuo@codeaurora.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
---
 arch/hexagon/Kconfig              |  220 +++++++++++++++++++++++++++++++++++++
 arch/hexagon/Makefile             |   59 ++++++++++
 arch/hexagon/kernel/Makefile      |   19 +++
 arch/hexagon/kernel/asm-offsets.c |  104 +++++++++++++++++
 arch/hexagon/kernel/vmlinux.lds.S |   93 ++++++++++++++++
 arch/hexagon/lib/Makefile         |    4 +
 arch/hexagon/mm/Makefile          |    7 +
 7 files changed, 506 insertions(+), 0 deletions(-)
 create mode 100644 arch/hexagon/Kconfig
 create mode 100644 arch/hexagon/Makefile
 create mode 100644 arch/hexagon/kernel/Makefile
 create mode 100644 arch/hexagon/kernel/asm-offsets.c
 create mode 100644 arch/hexagon/kernel/vmlinux.lds.S
 create mode 100644 arch/hexagon/lib/Makefile
 create mode 100644 arch/hexagon/mm/Makefile

diff --git a/arch/hexagon/Kconfig b/arch/hexagon/Kconfig
new file mode 100644
index 0000000..02513c2
--- /dev/null
+++ b/arch/hexagon/Kconfig
@@ -0,0 +1,220 @@
+# Hexagon configuration
+comment "Linux Kernel Configuration for Hexagon"
+
+config HEXAGON
+	def_bool y
+	select HAVE_OPROFILE
+	select USE_GENERIC_SMP_HELPERS if SMP
+	# Other pending projects/to-do items.
+	# select HAVE_REGS_AND_STACK_ACCESS_API
+	# select HAVE_HW_BREAKPOINT if PERF_EVENTS
+	# select ARCH_HAS_CPU_IDLE_WAIT
+	# select ARCH_WANT_OPTIONAL_GPIOLIB
+	# select ARCH_REQUIRE_GPIOLIB
+	# select HAVE_CLK
+	# select IRQ_PER_CPU
+	select HAVE_IRQ_WORK
+	# select GENERIC_PENDING_IRQ if SMP
+	select GENERIC_ATOMIC64
+	select HAVE_PERF_EVENTS
+	select HAVE_GENERIC_HARDIRQS
+	select GENERIC_HARDIRQS_NO__DO_IRQ
+	select GENERIC_HARDIRQS_NO_DEPRECATED
+	# GENERIC_ALLOCATOR is used by dma_alloc_coherent()
+	select GENERIC_ALLOCATOR
+	select GENERIC_IRQ_SHOW
+	select HAVE_ARCH_KGDB
+	select HAVE_ARCH_TRACEHOOK
+	select NO_IOPORT
+	# mostly generic routines, with some accelerated ones
+	---help---
+	  Qualcomm Hexagon is a processor architecture designed for high
+	  performance and low power across a wide variety of applications.
+
+config HEXAGON_ARCH_V1
+	bool
+
+config HEXAGON_ARCH_V2
+	bool
+
+config HEXAGON_ARCH_V3
+	bool
+
+config HEXAGON_ARCH_V4
+	bool
+
+config FRAME_POINTER
+	def_bool y
+
+config LOCKDEP_SUPPORT
+	def_bool y
+
+config PCI
+	def_bool n
+
+config EARLY_PRINTK
+	def_bool y
+
+config KTIME_SCALAR
+	def_bool y
+
+config MMU
+	def_bool y
+
+config TRACE_IRQFLAGS_SUPPORT
+	def_bool y
+
+config GENERIC_CSUM
+	def_bool y
+
+#
+# Use the generic interrupt handling code in kernel/irq/:
+#
+config GENERIC_IRQ_PROBE
+	def_bool y
+
+config GENERIC_IOMAP
+	def_bool y
+
+#config ZONE_DMA
+#	bool
+#	default y
+
+config HAS_DMA
+	bool
+	select HAVE_DMA_ATTRS
+	default y
+
+config NEED_SG_DMA_LENGTH
+	def_bool y
+
+config RWSEM_GENERIC_SPINLOCK
+	def_bool n
+
+config RWSEM_XCHGADD_ALGORITHM
+	def_bool y
+
+config GENERIC_FIND_NEXT_BIT
+	def_bool y
+
+config GENERIC_HWEIGHT
+	def_bool y
+
+config GENERIC_TIME
+	def_bool y
+
+config GENERIC_CLOCKEVENTS
+	def_bool y
+
+config GENERIC_CLOCKEVENTS_BROADCAST
+	def_bool y
+
+config STACKTRACE_SUPPORT
+	def_bool y
+	select STACKTRACE
+
+config GENERIC_BUG
+	def_bool y
+	depends on BUG
+
+config BUG
+	def_bool y
+
+menu "Machine selection"
+
+choice
+	prompt "System type"
+	default HEXAGON_ARCH_V2
+
+config HEXAGON_COMET
+	bool "Comet Board"
+	select HEXAGON_ARCH_V2
+	---help---
+	  Support for the Comet platform.
+
+endchoice
+
+config HEXAGON_VM
+	def_bool y
+
+config CMDLINE
+	string "Default kernel command string"
+	default ""
+	help
+	  On some platforms, there is currently no way for the boot loader
+	  to pass arguments to the kernel. For these, you should supply some
+	  command-line options at build time by entering them here.  At a
+	  minimum, you should specify the memory size and the root device
+	  (e.g., mem=64M root=/dev/nfs).
+
+config HEXAGON_ANGEL_TRAPS
+	bool "Use Angel Traps"
+	default n
+	---help---
+	  Enable angel debug traps (for printk's).
+
+config SMP
+	bool "Multi-Processing support"
+	---help---
+	  Enables SMP support in the kernel.  If unsure, say "Y"
+
+config NR_CPUS
+	int "Maximum number of CPUs" if SMP
+	range 2 6 if SMP
+	default "1" if !SMP
+	default "6" if SMP
+	---help---
+	  This allows you to specify the maximum number of CPUs which this
+	  kernel will support.  The maximum supported value is 6 and the
+	  minimum value which makes sense is 2.
+
+	  This is purely to save memory - each supported CPU adds
+	  approximately eight kilobytes to the kernel image.
+
+choice
+	prompt "Kernel page size"
+	default PAGE_SIZE_4KB
+	---help---
+	  Changes the default page size; use with caution.
+
+config PAGE_SIZE_4KB
+	bool "4KB"
+
+config PAGE_SIZE_16KB
+	bool "16KB"
+
+config PAGE_SIZE_64KB
+	bool "64KB"
+
+config PAGE_SIZE_256KB
+	bool "256KB"
+
+endchoice
+
+source "mm/Kconfig"
+
+source "kernel/Kconfig.hz"
+source "kernel/time/Kconfig"
+
+config GENERIC_GPIO
+	bool "Generic GPIO support"
+	default n
+
+endmenu
+
+source "init/Kconfig"
+source "drivers/Kconfig"
+source "fs/Kconfig"
+
+menu "Executable File Formats"
+source "fs/Kconfig.binfmt"
+endmenu
+
+source "net/Kconfig"
+source "security/Kconfig"
+source "crypto/Kconfig"
+source "lib/Kconfig"
+
+menu "Kernel hacking"
+source "lib/Kconfig.debug"
+endmenu
diff --git a/arch/hexagon/Makefile b/arch/hexagon/Makefile
new file mode 100644
index 0000000..7ce9563
--- /dev/null
+++ b/arch/hexagon/Makefile
@@ -0,0 +1,59 @@
+#  Makefile for the Hexagon arch
+
+KBUILD_DEFCONFIG = comet_defconfig
+
+# Do not use GP-relative jumps
+KBUILD_CFLAGS += -G0
+LDFLAGS_vmlinux += -G0
+
+# Do not use single-byte enums; these will overflow.
+KBUILD_CFLAGS += -fno-short-enums
+
+# Modules must use either long-calls, or use pic/plt.
+# Use long-calls for now, it's easier.  And faster.
+# CFLAGS_MODULE += -fPIC
+# LDFLAGS_MODULE += -shared
+CFLAGS_MODULE += -mlong-calls
+
+cflags-$(CONFIG_HEXAGON_ARCH_V1) += $(call cc-option,-mv1)
+cflags-$(CONFIG_HEXAGON_ARCH_V2) += $(call cc-option,-mv2)
+cflags-$(CONFIG_HEXAGON_ARCH_V3) += $(call cc-option,-mv3)
+cflags-$(CONFIG_HEXAGON_ARCH_V4) += $(call cc-option,-mv4)
+
+aflags-$(CONFIG_HEXAGON_ARCH_V1) += $(call cc-option,-mv1)
+aflags-$(CONFIG_HEXAGON_ARCH_V2) += $(call cc-option,-mv2)
+aflags-$(CONFIG_HEXAGON_ARCH_V3) += $(call cc-option,-mv3)
+aflags-$(CONFIG_HEXAGON_ARCH_V4) += $(call cc-option,-mv4)
+
+ldflags-$(CONFIG_HEXAGON_ARCH_V1) += $(call cc-option,-mv1)
+ldflags-$(CONFIG_HEXAGON_ARCH_V2) += $(call cc-option,-mv2)
+ldflags-$(CONFIG_HEXAGON_ARCH_V3) += $(call cc-option,-mv3)
+ldflags-$(CONFIG_HEXAGON_ARCH_V4) += $(call cc-option,-mv4)
+
+KBUILD_CFLAGS += $(cflags-y)
+KBUILD_AFLAGS += $(aflags-y)
+
+#  no KBUILD_LDFLAGS?
+LDFLAGS += $(ldflags-y)
+
+# Thread-info register will be r19.  This value is not configureable;
+# it is hard-coded in several files.
+TIR_NAME := r19
+KBUILD_CFLAGS += -ffixed-$(TIR_NAME) -DTHREADINFO_REG=$(TIR_NAME) -D__linux__
+KBUILD_AFLAGS += -DTHREADINFO_REG=$(TIR_NAME)
+
+LIBGCC := $(shell $(CC) $(KBUILD_CFLAGS) -print-libgcc-file-name)
+libs-y += $(LIBGCC)
+
+head-y := arch/hexagon/kernel/head.o \
+	arch/hexagon/kernel/init_task.o
+
+core-y += arch/hexagon/kernel/ \
+	arch/hexagon/mm/ \
+	arch/hexagon/lib/
+
+#	arch/hexagon/platform/common/
+#
+#core-$(CONFIG_HEXAGON_COMET)		+= arch/hexagon/platform/comet/
+#machine-$(CONFIG_HEXAGON_COMET)		:= comet
+
diff --git a/arch/hexagon/kernel/Makefile b/arch/hexagon/kernel/Makefile
new file mode 100644
index 0000000..27be2f6
--- /dev/null
+++ b/arch/hexagon/kernel/Makefile
@@ -0,0 +1,19 @@
+extra-y := head.o vmlinux.lds init_task.o
+
+obj-$(CONFIG_SMP) += smp.o topology.o
+
+obj-y += setup.o irq_cpu.o traps.o syscalltab.o signal.o time.o
+obj-y += process.o syscall.o trampoline.o reset.o ptrace.o
+obj-y += vdso.o
+
+obj-$(CONFIG_KGDB)    += kgdb.o
+obj-$(CONFIG_MODULES) += module.o hexagon_ksyms.o
+
+# Modules required to work with the Hexagon Virtual Machine
+obj-y += vm_entry.o vm_events.o vm_switch.o vm_ops.o vm_init_segtable.o
+obj-y += vm_vectors.o
+
+obj-$(CONFIG_HAS_DMA) += dma.o
+
+obj-$(CONFIG_STACKTRACE) += stacktrace.o
+
diff --git a/arch/hexagon/kernel/asm-offsets.c b/arch/hexagon/kernel/asm-offsets.c
new file mode 100644
index 0000000..89ffa51
--- /dev/null
+++ b/arch/hexagon/kernel/asm-offsets.c
@@ -0,0 +1,104 @@
+/*
+ * Copyright (C) 1996 David S. Miller
+ * Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003 Ralf Baechle
+ * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
+ * Kevin Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com
+ * Copyright (C) 2000 MIPS Technologies, Inc.
+ *
+ * Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+
+#include <linux/compat.h>
+#include <linux/types.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/interrupt.h>
+#include <linux/kbuild.h>
+#include <asm/ptrace.h>
+#include <asm/processor.h>
+
+/*  This file is used to produce asm/linkerscript constants from header
+    files typically used in c.  Specifically, it generates asm-offsets.h  */
+
+int main(void)
+{
+	COMMENT("This is a comment.");
+	/*  might get these from somewhere else.  */
+	DEFINE(_PAGE_SIZE, PAGE_SIZE);
+	DEFINE(_PAGE_SHIFT, PAGE_SHIFT);
+	BLANK();
+
+	COMMENT("Hexagon pt_regs definitions");
+	OFFSET(_PT_SYSCALL_NR, pt_regs, syscall_nr);
+	OFFSET(_PT_UGPGP, pt_regs, ugpgp);
+	OFFSET(_PT_R3130, pt_regs, r3130);
+	OFFSET(_PT_R2928, pt_regs, r2928);
+	OFFSET(_PT_R2726, pt_regs, r2726);
+	OFFSET(_PT_R2524, pt_regs, r2524);
+	OFFSET(_PT_R2322, pt_regs, r2322);
+	OFFSET(_PT_R2120, pt_regs, r2120);
+	OFFSET(_PT_R1918, pt_regs, r1918);
+	OFFSET(_PT_R1716, pt_regs, r1716);
+	OFFSET(_PT_R1514, pt_regs, r1514);
+	OFFSET(_PT_R1312, pt_regs, r1312);
+	OFFSET(_PT_R1110, pt_regs, r1110);
+	OFFSET(_PT_R0908, pt_regs, r0908);
+	OFFSET(_PT_R0706, pt_regs, r0706);
+	OFFSET(_PT_R0504, pt_regs, r0504);
+	OFFSET(_PT_R0302, pt_regs, r0302);
+	OFFSET(_PT_R0100, pt_regs, r0100);
+	OFFSET(_PT_LC0SA0, pt_regs, lc0sa0);
+	OFFSET(_PT_LC1SA1, pt_regs, lc1sa1);
+	OFFSET(_PT_M1M0, pt_regs, m1m0);
+	OFFSET(_PT_PREDSUSR, pt_regs, predsusr);
+	OFFSET(_PT_EVREC, pt_regs, hvmer);
+	OFFSET(_PT_ER_VMEL, pt_regs, hvmer.vmel);
+	OFFSET(_PT_ER_VMEST, pt_regs, hvmer.vmest);
+	OFFSET(_PT_ER_VMPSP, pt_regs, hvmer.vmpsp);
+	OFFSET(_PT_ER_VMBADVA, pt_regs, hvmer.vmbadva);
+	DEFINE(_PT_REGS_SIZE, sizeof(struct pt_regs));
+	BLANK();
+
+	COMMENT("Hexagon thread_info definitions");
+	OFFSET(_THREAD_INFO_FLAGS, thread_info, flags);
+	OFFSET(_THREAD_INFO_PT_REGS, thread_info, regs);
+	OFFSET(_THREAD_INFO_SP, thread_info, sp);
+	DEFINE(_THREAD_SIZE, THREAD_SIZE);
+	BLANK();
+
+	COMMENT("Hexagon hexagon_switch_stack definitions");
+	OFFSET(_SWITCH_R1716, hexagon_switch_stack, r1716);
+	OFFSET(_SWITCH_R1918, hexagon_switch_stack, r1918);
+	OFFSET(_SWITCH_R2120, hexagon_switch_stack, r2120);
+	OFFSET(_SWITCH_R2322, hexagon_switch_stack, r2322);
+
+	OFFSET(_SWITCH_R2524, hexagon_switch_stack, r2524);
+	OFFSET(_SWITCH_R2726, hexagon_switch_stack, r2726);
+	OFFSET(_SWITCH_FP, hexagon_switch_stack, fp);
+	OFFSET(_SWITCH_LR, hexagon_switch_stack, lr);
+	DEFINE(_SWITCH_STACK_SIZE, sizeof(struct hexagon_switch_stack));
+	BLANK();
+
+	COMMENT("Hexagon task_struct definitions");
+	OFFSET(_TASK_THREAD_INFO, task_struct, stack);
+	OFFSET(_TASK_STRUCT_THREAD, task_struct, thread);
+
+	COMMENT("Hexagon thread_struct definitions");
+	OFFSET(_THREAD_STRUCT_SWITCH_SP, thread_struct, switch_sp);
+
+	return 0;
+}
diff --git a/arch/hexagon/kernel/vmlinux.lds.S b/arch/hexagon/kernel/vmlinux.lds.S
new file mode 100644
index 0000000..362742f
--- /dev/null
+++ b/arch/hexagon/kernel/vmlinux.lds.S
@@ -0,0 +1,93 @@
+/*
+ * Linker script for Hexagon kernel
+ *
+ * Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+
+#define LOAD_OFFSET PAGE_OFFSET
+
+#include <asm-generic/vmlinux.lds.h>
+#include <asm/asm-offsets.h>	/*  Most of the kernel defines are here  */
+#include <asm/mem-layout.h>	/*  except for page_offset  */
+#include <asm/cache.h>		/*  and now we're pulling cache line size  */
+OUTPUT_ARCH(hexagon)
+ENTRY(stext)
+
+jiffies = jiffies_64;
+
+/*
+See asm-generic/vmlinux.lds.h for expansion of some of these macros.
+See asm-generic/sections.h for seemingly required labels.
+*/
+
+#define PAGE_SIZE _PAGE_SIZE
+
+/*  This LOAD_OFFSET is temporary for debugging on the simulator; it may change
+    for hypervisor pseudo-physical memory.  */
+
+
+SECTIONS
+{
+	. = PAGE_OFFSET + LOAD_ADDRESS;
+
+	__init_begin = .;
+	HEAD_TEXT_SECTION
+	INIT_TEXT_SECTION(PAGE_SIZE)
+	PERCPU_SECTION(L1_CACHE_BYTES)
+	__init_end = .;
+
+        . = ALIGN(_PAGE_SIZE);
+	_stext = .;
+	.text : AT(ADDR(.text) - LOAD_OFFSET) {
+		_text = .;
+		TEXT_TEXT
+		SCHED_TEXT
+		LOCK_TEXT
+		KPROBES_TEXT
+		*(.fixup)
+	}
+	_etext = .;
+
+	INIT_DATA_SECTION(PAGE_SIZE)
+
+	_sdata = .;
+		RW_DATA_SECTION(32,PAGE_SIZE,PAGE_SIZE)
+		RO_DATA_SECTION(PAGE_SIZE)
+	_edata = .;
+
+	EXCEPTION_TABLE(16)
+	NOTES
+
+	BSS_SECTION(_PAGE_SIZE, _PAGE_SIZE, _PAGE_SIZE)
+
+	_end = .;
+
+	/DISCARD/ : {
+		EXIT_TEXT
+		EXIT_DATA
+		EXIT_CALL
+	}
+
+	STABS_DEBUG
+	DWARF_DEBUG
+
+}
+
+
+
+
+
diff --git a/arch/hexagon/lib/Makefile b/arch/hexagon/lib/Makefile
new file mode 100644
index 0000000..874655e
--- /dev/null
+++ b/arch/hexagon/lib/Makefile
@@ -0,0 +1,4 @@
+#
+# Makefile for hexagon-specific library files.
+#
+obj-y = checksum.o io.o memcpy.o memset.o
diff --git a/arch/hexagon/mm/Makefile b/arch/hexagon/mm/Makefile
new file mode 100644
index 0000000..018be76
--- /dev/null
+++ b/arch/hexagon/mm/Makefile
@@ -0,0 +1,7 @@
+#
+# Makefile for Hexagon memory management subsystem
+#
+
+obj-y := init.o pgalloc.o ioremap.o uaccess.o vm_fault.o cache.o
+obj-y += copy_to_user.o copy_from_user.o strnlen_user.o vm_tlb.o
+
-- 
1.7.1


--

Sent by an employee of the Qualcomm Innovation Center, Inc.
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum.

Re: [PATCH v5 33/36] Hexagon: Add configuration and makefiles for the Hexagon architecture.

[Richard Kuo]

On Tue, Nov 01, 2011 at 10:30:46AM +0100, Paul Bolle wrote:
> (I'd like to add some quick comments, Kconfig related. It's too late, I
> guess.)

Sure, always appreciated.
 
> On Mon, 2011-10-31 at 18:55 -0500, Richard Kuo wrote:
> > +	# select GENERIC_PENDING_IRQ if SMP
> 
> Is GENERIC_PENDING_IRQ also a pending project?

Yes.
 
> > +	# mostly generic routines, with some accelerated ones
> 
> What does this comment on?

That was an early debugging thing that was removed; missed the comment
the comment that went with it.
 
> > +#config ZONE_DMA
> > +#	bool
> > +#	default y
> 
> Why is this added commented out?

We were using it before, but not anymore.

> > +config HAS_DMA
> > +	bool
> > +	select HAVE_DMA_ATTRS
> > +	default y
> 
> HAS_DMA isn't supposed to be used this way, is it? See commit
> 411f0f3edc141a582190d3605cadd1d993abb6df ("Introduce CONFIG_HAS_DMA").
> Can't this entry be replaced by a "select HAVE_DMA_ATTRS" line in the
> "config HEXAGON" entry? That seems to be the common idiom.

Yes, that appears to be the more appropriate way to select it.

> > +config STACKTRACE_SUPPORT
> > +	def_bool y
> > +	select STACKTRACE
> 
> Some grepping suggests that the tracing infrastructure will "select
> STACKTRACE" if the architecture sets STACKTRACE_SUPPORT (tile apparently
> also gets this wrong). Have I grepped this correctly?

Only if DEBUG_KMEMLEAK is selected apparently (?)

> > +config GENERIC_BUG
> > +	def_bool y
> > +	depends on BUG
> > +
> > +config BUG
> > +	def_bool y
> 
> Why do you have this? Other architecture don't (there's just one BUG
> entry in all the Kconfig files).

Thought we needed it; didn't realize it was in init/Kconfig.

> > +menu "Machine selection"
> > +
> > +choice
> > +	prompt "System type"
> > +	default HEXAGON_ARCH_V2
> > +
> > +config HEXAGON_COMET
> > +	bool "Comet Board"
> > +	select HEXAGON_ARCH_V2
> > +	---help---
> > +	  Support for the Comet platform.
> > +
> > +endchoice
> 
> The default doesn't match the (single) config option here (it should
> default to HEXAGON_COMET). That shouldn't matter because there's only
> one option, which the config tools will then pick (that's the way they
> seem to work). 
> 
> But why is this a choice when there's nothing to actually choose?
> Moreover, just looking at this patch suggests HEXAGON_COMET is yet
> unused (CONFIG_HEXAGON_COMET is commented out in the Makefile). So at
> first glance this seems an elaborate way to select HEXAGON_ARCH_V2.

Yes...  need to fix that default.

We felt it was better to remove the platform code for this submission
as it was not exactly clean and did not use the devtree code.  That's
why it's commented out of the Makefiles.

> > +config SMP
> > +	bool "Multi-Processing support"
> > +	---help---
> > +	  Enables SMP support in the kernel.  If unsure, say "Y"
> 
> Odd. Even x86 and powerpc (the only two architectures I looked at)
> suggest to say "N" to those not knowing what to do here.

I think for us, I think most people will want an SMP kernel.

> > +config GENERIC_GPIO
> > +	bool "Generic GPIO support"
> > +	default n
> 
> I know next to nothing about GENERIC_GPIO but does it make sense for
> Hexagon? If not, wouldn't a "def_bool n" do? (Perhaps you could even
> drop this entry entirely.)

We have another platform that does use it, but yes, a "def_bool n" 
will suffice.

I'll have these cleaned up in my local tree and produce a followup
patch if necessary...


Thanks for the feedback.
-Richard Kuo
 

-- 

Sent by an employee of the Qualcomm Innovation Center, Inc.
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum.

Re: [PATCH v5 33/36] Hexagon: Add configuration and makefiles for the Hexagon architecture.

[Paul Bolle]

On Tue, 2011-11-01 at 12:27 -0500, Richard Kuo wrote:
> On Tue, Nov 01, 2011 at 10:30:46AM +0100, Paul Bolle wrote:
> > Is GENERIC_PENDING_IRQ also a pending project?
> 
> Yes.

So, you'll move it up a line?
 
> > > +#config ZONE_DMA
> > > +#	bool
> > > +#	default y
> > 
> > Why is this added commented out?
> 
> We were using it before, but not anymore.

So, please drop it.

> > > +config STACKTRACE_SUPPORT
> > > +	def_bool y
> > > +	select STACKTRACE
> > 
> > Some grepping suggests that the tracing infrastructure will "select
> > STACKTRACE" if the architecture sets STACKTRACE_SUPPORT (tile apparently
> > also gets this wrong). Have I grepped this correctly?
> 
> Only if DEBUG_KMEMLEAK is selected apparently (?)

But "config TRACING" (in kernel/trace/Kconfig) also selects it if
STACKTRACE_SUPPORT is set. It seems GENERIC_TRACER is the hidden magic
here. GENERIC_TRACER is selected by the various tracer options - see
kernel/trace/Kconfig again, I'm unfamiliar with this stuff - and will
itself select TRACING. So if an arch has STACKTRACE_SUPPORT set it
doesn't have to select STACKTRACE itself. (Note that - except for tile -
no other arch selects STACKTRACE.) 

But hopefully someone who doesn't have to grep the Kconfig files to
understand this, can tell us for sure.

> We felt it was better to remove the platform code for this submission
> as it was not exactly clean and did not use the devtree code.  That's
> why it's commented out of the Makefiles.

If you really feel you need to add it, but commented out, perhaps a
comment can be added to keep people like me from submitting patches to
remove it.


Paul Bolle

Re: [PATCH v5 33/36] Hexagon: Add configuration and makefiles for the Hexagon architecture.

[Richard Kuo]

On Tue, Nov 01, 2011 at 07:59:52PM +0100, Paul Bolle wrote:
> So, you'll move it up a line?
>  
> > > > +#config ZONE_DMA
> > > > +#	bool
> > > > +#	default y
> > > 
> > > Why is this added commented out?
> > 
> > We were using it before, but not anymore.
> 
> So, please drop it.

Yes to both of these.

> But "config TRACING" (in kernel/trace/Kconfig) also selects it if
> STACKTRACE_SUPPORT is set. It seems GENERIC_TRACER is the hidden magic
> here. GENERIC_TRACER is selected by the various tracer options - see
> kernel/trace/Kconfig again, I'm unfamiliar with this stuff - and will
> itself select TRACING. So if an arch has STACKTRACE_SUPPORT set it
> doesn't have to select STACKTRACE itself. (Note that - except for tile -
> no other arch selects STACKTRACE.) 
> 
> But hopefully someone who doesn't have to grep the Kconfig files to
> understand this, can tell us for sure.

Ah...  Well, if nothing else, I'll just try not setting it and see if it
works as it seems to be intended.
 
> If you really feel you need to add it, but commented out, perhaps a
> comment can be added to keep people like me from submitting patches to
> remove it.

Sounds reasonable.  I'll either add a comment or just remove it
altogether (which is the long term goal).

Not that I mind getting patches, of course.

I'll have all these fixed in my tree and push them out when I can.


Thanks,
Richard Kuo

-- 

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