@@ -2123,6 +2123,7 @@ L: linux-arm-kernel@lists.infradead.org (moderated for non-subscribers)
S: Maintained
W: http://linux-chenxing.org/
F: Documentation/devicetree/bindings/arm/mstar.yaml
+F: arch/arm/mach-mstar/
ARM/NEC MOBILEPRO 900/c MACHINE SUPPORT
M: Michael Petchkovsky <mkpetch@internode.on.net>
@@ -668,6 +668,8 @@ source "arch/arm/mach-mmp/Kconfig"
source "arch/arm/mach-moxart/Kconfig"
+source "arch/arm/mach-mstar/Kconfig"
+
source "arch/arm/mach-mv78xx0/Kconfig"
source "arch/arm/mach-mvebu/Kconfig"
@@ -197,6 +197,7 @@ machine-$(CONFIG_ARCH_MXC) += imx
machine-$(CONFIG_ARCH_MEDIATEK) += mediatek
machine-$(CONFIG_ARCH_MILBEAUT) += milbeaut
machine-$(CONFIG_ARCH_MXS) += mxs
+machine-$(CONFIG_ARCH_MSTARV7) += mstar
machine-$(CONFIG_ARCH_NOMADIK) += nomadik
machine-$(CONFIG_ARCH_NPCM) += npcm
machine-$(CONFIG_ARCH_NSPIRE) += nspire
new file mode 100644
@@ -0,0 +1,26 @@
+menuconfig ARCH_MSTARV7
+ bool "MStar/Sigmastar Armv7 SoC Support"
+ depends on ARCH_MULTI_V7
+ select ARM_GIC
+ select ARM_HEAVY_MB
+ help
+ Support for newer MStar/Sigmastar SoC families that are
+ based on Armv7 cores like the Cortex A7 and share the same
+ basic hardware like the infinity and mercury series.
+
+if ARCH_MSTARV7
+
+config MACH_INFINITY
+ bool "MStar/Sigmastar infinity SoC support"
+ default ARCH_MSTARV7
+ help
+ Support for MStar/Sigmastar infinity IP camera SoCs.
+
+config MACH_MERCURY
+ bool "MStar/Sigmastar mercury SoC support"
+ default ARCH_MSTARV7
+ help
+ Support for MStar/Sigmastar mercury dash camera SoCs.
+ Note that older Mercury2 SoCs are ARM9 based and not supported.
+
+endif
new file mode 100644
@@ -0,0 +1 @@
+obj-$(CONFIG_ARCH_MSTARV7) += mstarv7.o
new file mode 100644
@@ -0,0 +1,80 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Device Tree support for MStar/Sigmastar Armv7 SoCs
+ *
+ * Copyright (c) 2020 thingy.jp
+ * Author: Daniel Palmer <daniel@thingy.jp>
+ */
+
+#include <linux/init.h>
+#include <asm/mach/arch.h>
+#include <asm/mach/map.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/io.h>
+
+/*
+ * In the u-boot code the area these registers are in is
+ * called "L3 bridge" and there are register descriptions
+ * for something in the same area called "AXI".
+ *
+ * It's not exactly known what this is but the vendor code
+ * for both u-boot and linux share calls to "flush the miu pipe".
+ * This seems to be to force pending CPU writes to memory so that
+ * the state is right before DMA capable devices try to read
+ * descriptors and data the CPU has prepared. Without doing this
+ * ethernet doesn't work reliably for example.
+ */
+
+#define MSTARV7_L3BRIDGE_FLUSH 0x14
+#define MSTARV7_L3BRIDGE_STATUS 0x40
+#define MSTARV7_L3BRIDGE_FLUSH_TRIGGER BIT(0)
+#define MSTARV7_L3BRIDGE_STATUS_DONE BIT(12)
+
+static void __iomem *l3bridge;
+
+static const char * const mstarv7_board_dt_compat[] __initconst = {
+ "mstar,infinity",
+ "mstar,infinity3",
+ "mstar,mercury5",
+ NULL,
+};
+
+/*
+ * This may need locking to deal with situations where an interrupt
+ * happens while we are in here and mb() gets called by the interrupt handler.
+ *
+ * The vendor code did have a spin lock but it doesn't seem to be needed and
+ * removing it hasn't caused any side effects so far.
+ *
+ * [writel|readl]_relaxed have to be used here because otherwise
+ * we'd end up right back in here.
+ */
+static void mstarv7_mb(void)
+{
+ /* toggle the flush miu pipe fire bit */
+ writel_relaxed(0, l3bridge + MSTARV7_L3BRIDGE_FLUSH);
+ writel_relaxed(MSTARV7_L3BRIDGE_FLUSH_TRIGGER, l3bridge
+ + MSTARV7_L3BRIDGE_FLUSH);
+ while (!(readl_relaxed(l3bridge + MSTARV7_L3BRIDGE_STATUS)
+ & MSTARV7_L3BRIDGE_STATUS_DONE)) {
+ /* wait for flush to complete */
+ }
+}
+
+static void __init mstarv7_init(void)
+{
+ struct device_node *np;
+
+ np = of_find_compatible_node(NULL, NULL, "mstar,l3bridge");
+ l3bridge = of_iomap(np, 0);
+ if (l3bridge)
+ soc_mb = mstarv7_mb;
+ else
+ pr_warn("Failed to install memory barrier, DMA will be broken!\n");
+}
+
+DT_MACHINE_START(MSTARV7_DT, "MStar/Sigmastar Armv7 (Device Tree)")
+ .dt_compat = mstarv7_board_dt_compat,
+ .init_machine = mstarv7_init,
+MACHINE_END
Initial support for the MStar/Sigmastar Armv7 based IP camera and dashcam SoCs. These chips are interesting in that they contain a Cortex-A7, peripherals and system memory in a single tiny QFN package that can be hand soldered allowing almost anyone to embed Linux in their projects. Signed-off-by: Daniel Palmer <daniel@0x0f.com> --- MAINTAINERS | 1 + arch/arm/Kconfig | 2 + arch/arm/Makefile | 1 + arch/arm/mach-mstar/Kconfig | 26 ++++++++++++ arch/arm/mach-mstar/Makefile | 1 + arch/arm/mach-mstar/mstarv7.c | 80 +++++++++++++++++++++++++++++++++++ 6 files changed, 111 insertions(+) create mode 100644 arch/arm/mach-mstar/Kconfig create mode 100644 arch/arm/mach-mstar/Makefile create mode 100644 arch/arm/mach-mstar/mstarv7.c