pci: Add Linux sysfs implementation of HW.PCI.Dev
In Linux' sysfs, each PCI device has a directory like:
/sys/devices/pci0000:00/0000:00:02.0/
Therein, the file `config` represents the PCI device's configuration
space. Alas, it's not mappable so we work on a read only copy. Should
we ever need dynamic read/write access, we'd have to implement it
using read()/write().
IO and MMIO resources are represented by mappable files, `resource[0-5]`
for uncacheable accesses and `resource[0-5]_wc` for write-combining
access.
Change-Id: I1358e9336edaf75e8eff50808a8169b997817d7e
Signed-off-by: Nico Huber <nico.h@gmx.de>
Reviewed-on: https://review.coreboot.org/20554
Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>
diff --git a/common/Makefile.inc b/common/Makefile.inc
index a8e7712..efdf21d 100644
--- a/common/Makefile.inc
+++ b/common/Makefile.inc
@@ -16,6 +16,8 @@
hw-$(CONFIG_HWBASE_DIRECT_PCIDEV) += direct/hw-pci-dev.adb
hw-$(CONFIG_HWBASE_DIRECT_PCIDEV) += hw-pci-dev.ads
+hw-$(CONFIG_HWBASE_LINUX_PCIDEV) += linux/hw-pci-dev.adb
+hw-$(CONFIG_HWBASE_LINUX_PCIDEV) += hw-pci-dev.ads
hw-config-ads := $(subst //,/,$(call src-to-obj,,$(dir)/hw-config).ads)
$(hw-config-ads): $(dir)/hw-config.ads.template $(cnf)
diff --git a/common/hw-pci-dev.ads b/common/hw-pci-dev.ads
index 90ed9e5..5b20aa1 100644
--- a/common/hw-pci-dev.ads
+++ b/common/hw-pci-dev.ads
@@ -48,6 +48,9 @@
procedure Resource_Size (Length : out Natural; Res : Resource);
+ pragma Warnings (GNATprove, Off, "unused variable ""MMConf_Base""*",
+ Reason => "Used for a common interface");
procedure Initialize (Success : out Boolean; MMConf_Base : Word64 := 0);
+ pragma Warnings (GNATprove, On, "unused variable ""MMConf_Base""*");
end HW.PCI.Dev;
diff --git a/common/linux/hw-pci-dev.adb b/common/linux/hw-pci-dev.adb
new file mode 100644
index 0000000..a768002
--- /dev/null
+++ b/common/linux/hw-pci-dev.adb
@@ -0,0 +1,148 @@
+--
+-- Copyright (C) 2017 Nico Huber <nico.h@gmx.de>
+--
+-- This program is free software; you can redistribute it and/or modify
+-- it under the terms of the GNU General Public License as published by
+-- the Free Software Foundation; either version 2 of the License, or
+-- (at your option) any later version.
+--
+-- This program is distributed in the hope that it will be useful,
+-- but WITHOUT ANY WARRANTY; without even the implied warranty of
+-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+-- GNU General Public License for more details.
+--
+
+with Ada.Text_IO;
+with Ada.Strings.Fixed;
+
+with HW.File;
+with HW.PCI.MMConf;
+
+with HW.MMIO_Range;
+pragma Elaborate_All (HW.MMIO_Range);
+
+use Ada.Strings.Fixed;
+
+package body HW.PCI.Dev
+with
+ Refined_State =>
+ (Address_State => MM.Address_State,
+ PCI_State => MM.PCI_State)
+is
+
+ -- We map each device's config space individually, hence Address'(0, 0, 0).
+ package MM is new HW.PCI.MMConf (Address'(0, 0, 0));
+
+ procedure Read8 (Value : out Word8; Offset : Index) renames MM.Read8;
+ procedure Read16 (Value : out Word16; Offset : Index) renames MM.Read16;
+ procedure Read32 (Value : out Word32; Offset : Index) renames MM.Read32;
+
+ procedure Write8 (Offset : Index; Value : Word8) renames MM.Write8;
+ procedure Write16 (Offset : Index; Value : Word16) renames MM.Write16;
+ procedure Write32 (Offset : Index; Value : Word32) renames MM.Write32;
+
+ function Hex (Val : Natural) return Character
+ with
+ Pre => Val < 16
+ is
+ begin
+ if Val < 10 then
+ return Character'Val (Character'Pos ('0') + Val);
+ else
+ return Character'Val (Character'Pos ('a') + Val - 10);
+ end if;
+ end Hex;
+
+ subtype String2 is String (1 .. 2);
+ function Hex2 (Val : Natural) return String2
+ with
+ Pre => Val < 256
+ is
+ Res : constant String (1 .. 2) := (Hex (Val / 16), Hex (Val mod 16));
+ begin
+ return Res;
+ end Hex2;
+
+ procedure Patch_Sysfs_Path (Path : in out String)
+ with
+ Pre => Path'Length >= 36
+ is
+ begin
+ Path (Path'First + 21 .. Path'First + 22) := Hex2 (Natural (Dev.Bus));
+ Path (Path'First + 29 .. Path'First + 30) := Hex2 (Natural (Dev.Bus));
+ Path (Path'First + 32 .. Path'First + 33) := Hex2 (Natural (Dev.Slot));
+ Path (Path'First + 35) := Hex (Natural (Dev.Func));
+ end Patch_Sysfs_Path;
+
+ procedure Map
+ (Addr : out Word64;
+ Res : in Resource;
+ Length : in Natural := 0;
+ Offset : in Natural := 0;
+ WC : in Boolean := False)
+ is
+ Success : Boolean;
+ Path : String (1 .. 49) :=
+ "/sys/devices/pci0000:xx/0000:xx:xx.x/resourcex_wc";
+ begin
+ Patch_Sysfs_Path (Path);
+ Path (46) := Character'Val (Character'Pos ('0') + Resource'Pos (Res));
+ if not WC then
+ Path (47) := Character'Val (0);
+ end if;
+
+ File.Map
+ (Addr => Addr,
+ Path => Path,
+ Len => Length,
+ Offset => Offset,
+ Readable => True,
+ Writable => True,
+ Success => Success);
+
+ if not Success and WC then -- try again without write-combining
+ Path (47) := Character'Val (0);
+
+ File.Map
+ (Addr => Addr,
+ Path => Path,
+ Len => Length,
+ Offset => Offset,
+ Readable => True,
+ Writable => True,
+ Success => Success);
+ end if;
+
+ if not Success then
+ Addr := 0;
+ end if;
+ end Map;
+
+ procedure Resource_Size (Length : out Natural; Res : Resource)
+ is
+ Path : String (1 .. 46) :=
+ "/sys/devices/pci0000:xx/0000:xx:xx.x/resourcex";
+ begin
+ Patch_Sysfs_Path (Path);
+ Path (46) := Character'Val (Character'Pos ('0') + Resource'Pos (Res));
+
+ File.Size (Length, Path);
+ end Resource_Size;
+
+ procedure Initialize (Success : out Boolean; MMConf_Base : Word64 := 0)
+ is
+ Addr : Word64;
+ Path : String (1 .. 43) := "/sys/devices/pci0000:xx/0000:xx:xx.x/config";
+ begin
+ Patch_Sysfs_Path (Path);
+
+ File.Map
+ (Addr => Addr,
+ Path => Path,
+ Readable => True,
+ Map_Copy => True,
+ Success => Success);
+ MM.Set_Base_Address (Addr);
+ end Initialize;
+
+end HW.PCI.Dev;