All of lore.kernel.org
 help / color / mirror / Atom feed
From: Marcelo Tosatti <marcelo@kvack.org>
To: Christoph Lameter <clameter@engr.sgi.com>,
	Andi Kleen <ak@suse.de>, Arjan van de Ven <arjan@infradead.org>,
	Arnd Bergmann <arnd@arndb.de>
Cc: linux-mm@kvack.org
Subject: [PATCH 1/2] optional GENERIC_ISA_DMA
Date: Thu, 28 Dec 2006 23:05:55 -0200	[thread overview]
Message-ID: <20061229010555.GA1116@dmt> (raw)

The following patch makes CONFIG_GENERIC_ISA_DMA/ISA_DMA_API a configure
option.

Newer/embedded systems usually do not have an ISA bus: kernel/dma.o and
arch/i386/kernel/i8237.o are dead code on such systems.

This is a preparation for the second patch: allow ZONE_DMA to be unset
on x86.

Against 2.6.20-rc2-mm1, on top of Christoph's ZONE_DMA work.

--- ./arch/i386/kernel/Makefile.orig	2006-12-28 22:56:50.000000000 -0200
+++ ./arch/i386/kernel/Makefile	2006-12-28 22:56:58.000000000 -0200
@@ -7,13 +7,14 @@
 obj-y	:= process.o signal.o entry.o traps.o irq.o \
 		ptrace.o time.o ioport.o ldt.o setup.o i8259.o sys_i386.o \
 		pci-dma.o i386_ksyms.o i387.o bootflag.o e820.o\
-		quirks.o i8237.o topology.o alternative.o i8253.o tsc.o
+		quirks.o topology.o alternative.o i8253.o tsc.o
 
 obj-$(CONFIG_STACKTRACE)	+= stacktrace.o
 obj-y				+= cpu/
 obj-y				+= acpi/
 obj-$(CONFIG_X86_BIOS_REBOOT)	+= reboot.o
 obj-$(CONFIG_MCA)		+= mca.o
+obj-$(CONFIG_GENERIC_ISA_DMA)	+= i8237.o
 obj-$(CONFIG_X86_MSR)		+= msr.o
 obj-$(CONFIG_X86_CPUID)		+= cpuid.o
 obj-$(CONFIG_MICROCODE)		+= microcode.o
--- ./arch/i386/Kconfig.orig	2006-12-28 22:56:43.000000000 -0200
+++ ./arch/i386/Kconfig	2006-12-28 22:58:14.000000000 -0200
@@ -53,10 +53,6 @@
 config SBUS
 	bool
 
-config GENERIC_ISA_DMA
-	bool
-	default y
-
 config GENERIC_IOMAP
 	bool
 	default y
@@ -1134,11 +1130,12 @@
 
 config ISA_DMA_API
 	bool
-	default y
+	default n
 
 config ISA
 	bool "ISA support"
 	depends on !(X86_VOYAGER || X86_VISWS)
+	select GENERIC_ISA_DMA
 	help
 	  Find out whether you have ISA slots on your motherboard.  ISA is the
 	  name of a bus system, i.e. the way the CPU talks to the other stuff
@@ -1146,6 +1143,21 @@
 	  (MCA) or VESA.  ISA is an older system, now being displaced by PCI;
 	  newer boards don't support it.  If you have ISA, say Y, otherwise N.
 
+config GENERIC_ISA_DMA
+	bool "ISA DMA API"
+	select ISA_DMA_API
+	default y
+	help
+	  This enables support for the ISA DMA API, which provides DMA
+	  channel management. Its automatically selected by CONFIG_ISA.
+
+	  Say N here if you do not have ISA devices on your x86 system.
+	  Doing so might disable the DMA zone (0-16MiB), which simplifies 
+	  virtual memory management.
+
+	  If unsure, say Y.
+
+
 config EISA
 	bool "EISA support"
 	depends on ISA

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

                 reply	other threads:[~2006-12-29  1:05 UTC|newest]

Thread overview: [no followups] expand[flat|nested]  mbox.gz  Atom feed

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20061229010555.GA1116@dmt \
    --to=marcelo@kvack.org \
    --cc=ak@suse.de \
    --cc=arjan@infradead.org \
    --cc=arnd@arndb.de \
    --cc=clameter@engr.sgi.com \
    --cc=linux-mm@kvack.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.