[PATCH] ARM: vexpress: initial device tree support

Dave Martin dave.martin at linaro.org
Wed Sep 21 19:19:46 EST 2011


This patch implements initial support for booting using a flattened
device tree on the Versatile Express platform.

Eventually, it should be possible to present a single, core-tile-
independent board, but in this transitional patch the baseboard +
Cortex-A9x4 core tile combination is the only directly supported
platform, since the implementation is not yet fully generic.

For now, clocks and timers are not handled via the device tree.
Implementation of these can follow in later patches.

Thanks to Lorenzo Pieralisi, Grant Likely and Paweł Moll for their
help and contributions.

Signed-off-by: Dave Martin <dave.martin at linaro.org>
Acked-by: Paweł Moll <Pawel.Moll at arm.com>
---

There are some outstanding issues which need to be discussed, listed
below.

  * This patch is not currently based on the GIC bindings being
    discussed by Rob Herring et al.  Once that discussion reaches a
    conclusion, it should be straightforward to rebase onto the result.

  * The following added bindings are not present upstream and need
    documentation / discussion:

      * arm,vexpress -- the global board binding for all platform
        combinations using the Versatile Express motherboard.

      * arm,vexpress-v2p-ca9 -- the specific binding for the Versatile
        Express motherboard with Cortex-A9x4 core tile installed.  It
        is only mentioned as the most-specific match in vexpress-v2p-
        ca9.dts

        Since it's intended that the motherboard code should be fully
        generic, and because no other core tiles are upstream yet,
        perhaps we can get rid of this binding right away.

      * edid -- It should be possible to have a fairly generic binding
        for EDID interfaces, but none seems to exist yet.  Discussion
        is needed regarding what form this should take.

        This might more appropriately be called "ddc" (or some
        variation on that), since EDID seems only to describe the
        format of the ID data retrievable via this interface; not the
        interface itself.

      * arm,vexpress-flash -- Needed because of the requirement to
        provide the physmap_flash driver with a special .set_vpp
        handler.

      * idt,89hpes32h8 -- This is the IDT 89HPES32H8 PCI express
        interconnect switch.  This isn't needed for the Versatile
        Express to work, but would be needed if using PCI-e peripherals
        for real.  I expect that more driver support needs to go
        upstream before this is actually usable.

      * nxp,isp1761 -- The driver support for this is already upstream
        (with some minor issues for ARM support).

      * arm,amba-bus -- widely used by other boards and patchsets, but
        seems not to be documented.

      * The following bindings for ARM primecell peripherals are used
        elsewhere but not documented.  They should be pretty simple and
        uncontraversial.
          * arm,pl031
          * arm,pl041
          * arm,pl050
          * arm,pl180
          * arm,sp805

        Rob Herring suggested documenting simple bindings for these
        (and others) along with his initial amba device tree probe
        patches, but these bindings don't seem to be documented
        upstream for now.


  * Shawn Guo's smsc911x patch is needed for Ethernet to work.  This is
    headed upstream but not yet in mainline.  It is available in -next.

  * Minor patches are needed to the isp1760 and pata_generic drivers,
    to allow OF-based initialisation across a wider group of
    architectures.  These are being discussed independently, but are
    not yet accepted for merging upstream.

  * Most core-tile peripherals are currently not described in the core-
    tile device tree fragment.  This is a lower-priority issue since
    the motherboard code already autodetects the core-tile (though only
    one core-tile is fully upstream at the moment).

  * Static peripheral mappings are not yet handled in a generic way in
    the board support code.  This is a prerequisite for supporting
    multiple core-tiles int the same kernel.  It well need to get fixed
    later, when extra core tile support is merged (or before).

    Paweł Moll is looking into this separately.

  * The Kconfig logic for ensuring that at least one boot protocol and
    at least one core tile are selected is a bit ugly.  Suggestions for
    improving this are certainly welcome.

 arch/arm/Kconfig                           |    1 +
 arch/arm/boot/dts/vexpress-v2m-legacy.dtsi |  163 ++++++++++++++++++++++++++++
 arch/arm/boot/dts/vexpress-v2p-ca9.dts     |   80 ++++++++++++++
 arch/arm/configs/vexpress_defconfig        |    1 +
 arch/arm/mach-vexpress/Kconfig             |   45 ++++++++-
 arch/arm/mach-vexpress/ct-ca9x4.c          |    7 ++
 arch/arm/mach-vexpress/v2m.c               |   54 +++++++++-
 7 files changed, 349 insertions(+), 2 deletions(-)
 create mode 100644 arch/arm/boot/dts/vexpress-v2m-legacy.dtsi
 create mode 100644 arch/arm/boot/dts/vexpress-v2p-ca9.dts

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 5ebc5d9..a6e90d5 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -282,6 +282,7 @@ config ARCH_VERSATILE
 
 config ARCH_VEXPRESS
 	bool "ARM Ltd. Versatile Express family"
+	select ARCH_VEXPRESS_SANE_CONFIG
 	select ARCH_WANT_OPTIONAL_GPIOLIB
 	select ARM_AMBA
 	select ARM_TIMER_SP804
diff --git a/arch/arm/boot/dts/vexpress-v2m-legacy.dtsi b/arch/arm/boot/dts/vexpress-v2m-legacy.dtsi
new file mode 100644
index 0000000..fd6e4e4
--- /dev/null
+++ b/arch/arm/boot/dts/vexpress-v2m-legacy.dtsi
@@ -0,0 +1,163 @@
+// ARM Ltd. Versatile Express Motherboard V2M-P1 (HBI-0190D)
+// Legacy memory map
+
+/ {
+	aliases {
+		serial0 = &uart0;
+		serial1 = &uart1;
+		serial2 = &uart2;
+		serial3 = &uart3;
+		i2c0 = &i2c0;
+		i2c1 = &i2c1;
+	};
+
+	motherboard {
+		compatible = "simple-bus";
+		#address-cells = <2>; // SMB chipselect number and offset
+		#size-cells = <1>;
+		#interrupt-cells = <1>;
+
+		flash at 0,00000000 {
+			compatible = "arm,vexpress-flash", "cfi-flash";
+			reg = <0 0x00000000 0x04000000
+			       1 0x00000000 0x04000000>;
+			bank-width = <4>;
+		};
+
+		psram at 2,00000000 {
+			compatible = "mtd-ram";
+			reg = <2 0x00000000 0x02000000>;
+			bank-width = <4>;
+		};
+
+		ethernet at 3,02000000 {
+			compatible = "smsc,lan9118", "smsc,lan9115";
+			reg = <3 0x02000000 0x10000>;
+			reg-io-width = <4>;
+			interrupts = <15>;
+			smsc,irq-active-high;
+			smsc,irq-push-pull;
+		};
+
+		usb at 3,03000000 {
+			compatible = "nxp,usb-isp1761";
+			reg = <3 0x03000000 0x20000>;
+			interrupts = <16>;
+			port1-otg;
+		};
+
+		peripherals at 7,00000000 {
+			compatible = "arm,amba-bus", "simple-bus";
+			#address-cells = <1>;
+			#size-cells = <1>;
+			ranges = <0 7 0 0x20000>;
+
+			// PCI-E I2C bus
+			i2c0: i2c at 02000 {
+				compatible = "arm,versatile-i2c";
+				reg = <0x02000 0x1000>;
+
+				#address-cells = <1>;
+				#size-cells = <0>;
+
+				pcie-switch at 60 {
+					compatible = "idt,89hpes32h8";
+					reg = <0x60>;
+				};
+			};
+
+			aaci at 04000 {
+				compatible = "arm,pl041", "arm,primecell";
+				reg = <0x04000 0x1000>;
+				interrupts = <11>;
+			};
+
+			mmci at 05000 {
+				compatible = "arm,pl180", "arm,primecell";
+				reg = <0x05000 0x1000>;
+				interrupts = <9 10>;
+			};
+
+			kmi at 06000 {
+				compatible = "arm,pl050", "arm,primecell";
+				reg = <0x06000 0x1000>;
+				interrupts = <12>;
+			};
+
+			kmi at 07000 {
+				compatible = "arm,pl050", "arm,primecell";
+				reg = <0x07000 0x1000>;
+				interrupts = <13>;
+			};
+
+			uart0: uart at 09000 {
+				compatible = "arm,pl011", "arm,primecell";
+				reg = <0x09000 0x1000>;
+				interrupts = <5>;
+			};
+
+			uart1: uart at 0a000 {
+				compatible = "arm,pl011", "arm,primecell";
+				reg = <0x0a000 0x1000>;
+				interrupts = <6>;
+			};
+
+			uart2: uart at 0b000 {
+				compatible = "arm,pl011", "arm,primecell";
+				reg = <0x0b000 0x1000>;
+				interrupts = <7>;
+			};
+
+			uart3: uart at 0c000 {
+				compatible = "arm,pl011", "arm,primecell";
+				reg = <0x0c000 0x1000>;
+				interrupts = <8>;
+			};
+
+			wdt at 0f000 {
+				compatible = "arm,sp805", "arm,primecell";
+				reg = <0x0f000 0x1000>;
+				interrupts = <0>;
+			};
+
+			// Timer init is hardcoded in v2m_timer_init(), for now.
+			// timer at 11000 {
+			//	compatible = "arm,arm-sp804";
+			//	reg = <0x11000 0x1000>;
+			//	interrupts = <2>;
+			// };
+
+			// timer at 12000 {
+			//	compatible = "arm,arm-sp804";
+			//	reg = <0x12000 0x1000>;
+			// };
+
+			// DVI I2C bus (DDC)
+			i2c1: i2c at 16000 {
+				compatible = "arm,versatile-i2c";
+				reg = <0x16000 0x1000>;
+
+				#address-cells = <1>;
+				#size-cells = <0>;
+
+				edid at 50 {
+					compatible = "edid";
+					reg = <0x50>;
+				};
+			};
+
+			rtc at 17000 {
+				compatible = "arm,pl031", "arm,primecell";
+				reg = <0x017000 0x1000>;
+				interrupts = <4>;
+			};
+
+			compact-flash at 1a000 {
+				compatible = "ata-generic";
+				reg = <0x1a000 0x100
+				       0x1a100 0xf00>;
+				reg-shift = <2>;
+			};
+		};
+	};
+};
diff --git a/arch/arm/boot/dts/vexpress-v2p-ca9.dts b/arch/arm/boot/dts/vexpress-v2p-ca9.dts
new file mode 100644
index 0000000..059be97
--- /dev/null
+++ b/arch/arm/boot/dts/vexpress-v2p-ca9.dts
@@ -0,0 +1,80 @@
+// ARM Ltd. Versatile Express Corex-A9 (Quad Core) Core Tile V2P-CA9 (HBI-0191B)
+
+/dts-v1/;
+
+/include/ "skeleton.dtsi"
+
+/ {
+	model = "ARM Versatile Express (Cortex-A9 Quad Core Tile)";
+	compatible = "arm,vexpress-v2p-ca9", "arm,vexpress";
+	interrupt-parent = <&intc>;
+
+	memory {
+		device_type = "memory";
+		reg = <0x60000000 0x40000000>;
+	};
+
+	intc: interrupt-controller at 1e001000 {
+		compatible = "arm,cortex-a9-gic";
+		#interrupt-cells = <2>;
+		#address-cells = <0>;
+		interrupt-controller;
+		reg = <0x1e001000 0x1000>,
+		      <0x1e000100 0x100>;
+	};
+
+	motherboard {
+		ranges = <0 0 0x40000000 0x04000000
+			  1 0 0x44000000 0x04000000
+			  2 0 0x48000000 0x04000000
+			  3 0 0x4c000000 0x04000000
+			  7 0 0x10000000 0x00020000>;
+
+		interrupt-map-mask = <0 0 63>;
+		interrupt-map = <0 0 0 &intc 32 8
+				 0 0 1 &intc 33 4
+				 0 0 2 &intc 34 4
+				 0 0 3 &intc 35 4
+				 0 0 4 &intc 36 4
+				 0 0 5 &intc 37 4
+				 0 0 6 &intc 38 4
+				 0 0 7 &intc 39 4
+				 0 0 8 &intc 40 4
+				 0 0 9 &intc 41 4
+				 0 0 10 &intc 42 4
+				 0 0 11 &intc 43 4
+				 0 0 12 &intc 44 4
+				 0 0 13 &intc 45 4
+				 0 0 14 &intc 46 4
+				 0 0 15 &intc 47 4
+				 0 0 16 &intc 48 4
+				 0 0 17 &intc 49 4
+				 0 0 18 &intc 50 4
+				 0 0 19 &intc 51 4
+				 0 0 20 &intc 52 4
+				 0 0 21 &intc 53 4
+				 0 0 22 &intc 54 4
+				 0 0 23 &intc 55 4
+				 0 0 24 &intc 56 4
+				 0 0 25 &intc 57 4
+				 0 0 26 &intc 58 4
+				 0 0 27 &intc 59 4
+				 0 0 28 &intc 60 4
+				 0 0 29 &intc 61 4
+				 0 0 30 &intc 62 4
+				 0 0 31 &intc 63 4
+				 0 0 32 &intc 64 4
+				 0 0 33 &intc 65 4
+				 0 0 34 &intc 66 4
+				 0 0 35 &intc 67 4
+				 0 0 36 &intc 68 4
+				 0 0 37 &intc 69 4
+				 0 0 38 &intc 70 4
+				 0 0 39 &intc 71 4
+				 0 0 40 &intc 72 4
+				 0 0 41 &intc 73 4
+				 0 0 42 &intc 74 4>;
+	};
+};
+
+/include/ "vexpress-v2m-legacy.dtsi"
diff --git a/arch/arm/configs/vexpress_defconfig b/arch/arm/configs/vexpress_defconfig
index f2de51f..6c3c5f6 100644
--- a/arch/arm/configs/vexpress_defconfig
+++ b/arch/arm/configs/vexpress_defconfig
@@ -22,6 +22,7 @@ CONFIG_MODULE_UNLOAD=y
 # CONFIG_IOSCHED_DEADLINE is not set
 # CONFIG_IOSCHED_CFQ is not set
 CONFIG_ARCH_VEXPRESS=y
+CONFIG_ARCH_VEXPRESS_ATAGS=y
 CONFIG_ARCH_VEXPRESS_CA9X4=y
 # CONFIG_SWP_EMULATE is not set
 CONFIG_SMP=y
diff --git a/arch/arm/mach-vexpress/Kconfig b/arch/arm/mach-vexpress/Kconfig
index 9311484..ea64630 100644
--- a/arch/arm/mach-vexpress/Kconfig
+++ b/arch/arm/mach-vexpress/Kconfig
@@ -1,12 +1,55 @@
 menu "Versatile Express platform type"
 	depends on ARCH_VEXPRESS
 
+# ARCH_VEXPRESS ensures a sane minimal config is selected by selecting
+# ARCH_VEXPRESS_SANE_CONFIG.
+# Extend the logic here when adding new core tiles.
+
+config ARCH_VEXPRESS_SANE_CONFIG
+	bool
+	select ARCH_VEXPRESS_CA9X4
+	select ARCH_VEXPRESS_ATAGS if !ARCH_VEXPRESS_DT
+
+
+comment "At least one boot type must be selected"
+
+config ARCH_VEXPRESS_ATAGS
+	bool "Boot via ATAGs"
+	default y
+	help
+	  This option enables support for the board using the standard
+	  ATAGs boot protocol.
+
+	  If your bootloader supports FDT-based booting and you do not
+	  intend ever to boot via the traditional ATAGs method, you can say
+	  N here.
+
+config ARCH_VEXPRESS_DT
+	bool "Boot via Device Tree"
+	select USE_OF
+	help
+	  This option enables support for the board, and enables booting
+	  via a Flattened Device Tree provided by the bootloader.
+
+	  If your bootloader supports FDT-based booting, you can say Y
+	  here, otherwise, say N.
+
+
+# Core Tile support options
+
+comment "At least one core tile must be selected"
+
 config ARCH_VEXPRESS_CA9X4
-	bool "Versatile Express Cortex-A9x4 tile"
+	bool "Versatile Express Cortex-A9x4 Core Tile"
+	default y
 	select CPU_V7
 	select ARM_GIC
 	select ARM_ERRATA_720789
 	select ARM_ERRATA_751472
 	select ARM_ERRATA_753970
+	help
+	  Include support for the Cortex-A9x4 Core Tile (HBI-0191B).
+
+	  If unsure, say Y.
 
 endmenu
diff --git a/arch/arm/mach-vexpress/ct-ca9x4.c b/arch/arm/mach-vexpress/ct-ca9x4.c
index bfd32f5..e2fe2c9 100644
--- a/arch/arm/mach-vexpress/ct-ca9x4.c
+++ b/arch/arm/mach-vexpress/ct-ca9x4.c
@@ -9,6 +9,7 @@
 #include <linux/amba/bus.h>
 #include <linux/amba/clcd.h>
 #include <linux/clkdev.h>
+#include <linux/irqdomain.h>
 
 #include <asm/hardware/arm_timer.h>
 #include <asm/hardware/cache-l2x0.h>
@@ -59,10 +60,16 @@ static void __init ct_ca9x4_map_io(void)
 	iotable_init(ct_ca9x4_io_desc, ARRAY_SIZE(ct_ca9x4_io_desc));
 }
 
+static const struct of_device_id gic_of_match[] __initconst = {
+	{ .compatible = "arm,cortex-a9-gic", },
+	{}
+};
+
 static void __init ct_ca9x4_init_irq(void)
 {
 	gic_init(0, 29, MMIO_P2V(A9_MPCORE_GIC_DIST),
 		 MMIO_P2V(A9_MPCORE_GIC_CPU));
+	irq_domain_generate_simple(gic_of_match, A9_MPCORE_GIC_DIST, 0);
 }
 
 #if 0
diff --git a/arch/arm/mach-vexpress/v2m.c b/arch/arm/mach-vexpress/v2m.c
index 9e6b93b..6defce6 100644
--- a/arch/arm/mach-vexpress/v2m.c
+++ b/arch/arm/mach-vexpress/v2m.c
@@ -6,6 +6,8 @@
 #include <linux/amba/mmci.h>
 #include <linux/io.h>
 #include <linux/init.h>
+#include <linux/of_irq.h>
+#include <linux/of_platform.h>
 #include <linux/platform_device.h>
 #include <linux/ata_platform.h>
 #include <linux/smsc911x.h>
@@ -118,7 +120,7 @@ int v2m_cfg_read(u32 devfn, u32 *data)
 	return !!(val & SYS_CFG_ERR);
 }
 
-
+#ifdef CONFIG_ARCH_VEXPRESS_ATAGS
 static struct resource v2m_pcie_i2c_resource = {
 	.start	= V2M_SERIAL_BUS_PCI,
 	.end	= V2M_SERIAL_BUS_PCI + SZ_4K - 1,
@@ -200,6 +202,7 @@ static struct platform_device v2m_usb_device = {
 	.num_resources	= ARRAY_SIZE(v2m_usb_resources),
 	.dev.platform_data = &v2m_usb_config,
 };
+#endif /* CONFIG_ARCH_VEXPRESS_ATAGS */
 
 static void v2m_flash_set_vpp(struct platform_device *pdev, int on)
 {
@@ -211,6 +214,7 @@ static struct physmap_flash_data v2m_flash_data = {
 	.set_vpp	= v2m_flash_set_vpp,
 };
 
+#ifdef CONFIG_ARCH_VEXPRESS_ATAGS
 static struct resource v2m_flash_resources[] = {
 	{
 		.start	= V2M_NOR0,
@@ -254,6 +258,7 @@ static struct platform_device v2m_cf_device = {
 	.num_resources	= ARRAY_SIZE(v2m_pata_resources),
 	.dev.platform_data = &v2m_pata_data,
 };
+#endif /* CONFIG_ARCH_VEXPRESS_ATAGS */
 
 static unsigned int v2m_mmci_status(struct device *dev)
 {
@@ -265,6 +270,7 @@ static struct mmci_platform_data v2m_mmci_data = {
 	.status		= v2m_mmci_status,
 };
 
+#ifdef CONFIG_ARCH_VEXPRESS_ATAGS
 static AMBA_DEVICE(aaci,  "mb:aaci",  V2M_AACI, NULL);
 static AMBA_DEVICE(mmci,  "mb:mmci",  V2M_MMCI, &v2m_mmci_data);
 static AMBA_DEVICE(kmi0,  "mb:kmi0",  V2M_KMI0, NULL);
@@ -288,6 +294,7 @@ static struct amba_device *v2m_amba_devs[] __initdata = {
 	&wdt_device,
 	&rtc_device,
 };
+#endif /* CONFIG_ARCH_VEXPRESS_ATAGS */
 
 
 static long v2m_osc_round(struct clk *clk, unsigned long rate)
@@ -415,6 +422,8 @@ static void __init v2m_init_irq(void)
 	ct_desc->init_irq();
 }
 
+
+#ifdef CONFIG_ARCH_VEXPRESS_ATAGS
 static void __init v2m_init(void)
 {
 	int i;
@@ -443,3 +452,46 @@ MACHINE_START(VEXPRESS, "ARM-Versatile Express")
 	.timer		= &v2m_timer,
 	.init_machine	= v2m_init,
 MACHINE_END
+#endif /* CONFIG_ARCH_VEXPRESS_ATAGS */
+
+#ifdef CONFIG_ARCH_VEXPRESS_DT
+struct of_dev_auxdata v2m_dt_auxdata_lookup[] __initdata = {
+	OF_DEV_AUXDATA("arm,vexpress-flash", V2M_NOR0, "physmap-flash", &v2m_flash_data),
+	OF_DEV_AUXDATA("arm,primecell", V2M_AACI, "mb:aaci", NULL),
+	OF_DEV_AUXDATA("arm,primecell", V2M_WDT, "mb:wdt", NULL),
+	OF_DEV_AUXDATA("arm,primecell", V2M_MMCI, "mb:mmci", &v2m_mmci_data),
+	OF_DEV_AUXDATA("arm,primecell", V2M_KMI0, "mb:kmi0", NULL),
+	OF_DEV_AUXDATA("arm,primecell", V2M_KMI1, "mb:kmi1", NULL),
+	OF_DEV_AUXDATA("arm,primecell", V2M_UART0, "mb:uart0", NULL),
+	OF_DEV_AUXDATA("arm,primecell", V2M_UART1, "mb:uart1", NULL),
+	OF_DEV_AUXDATA("arm,primecell", V2M_UART2, "mb:uart2", NULL),
+	OF_DEV_AUXDATA("arm,primecell", V2M_UART3, "mb:uart3", NULL),
+	OF_DEV_AUXDATA("arm,primecell", V2M_RTC, "mb:rtc", NULL),
+	{}
+};
+
+static void __init v2m_dt_init(void)
+{
+	of_platform_populate(NULL, of_default_bus_match_table,
+			     v2m_dt_auxdata_lookup, NULL);
+
+	pm_power_off = v2m_power_off;
+	arm_pm_restart = v2m_restart;
+
+	ct_desc->init_tile();
+}
+
+static const char *v2m_dt_match[] __initconst = {
+	"arm,vexpress",
+	NULL,
+};
+
+DT_MACHINE_START(VEXPRESS_DT, "ARM Versatile Express")
+	.map_io		= v2m_map_io,
+	.init_early	= v2m_init_early,
+	.init_irq	= v2m_init_irq,
+	.timer		= &v2m_timer,
+	.init_machine	= v2m_dt_init,
+	.dt_compat	= v2m_dt_match,
+MACHINE_END
+#endif /* CONFIG_ARCH_VEXPRESS_DT */
-- 
1.7.4.1



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