[PATCH v3 2/4] MIPS: Add Realtek RTL838x/RTL839x support as generic MIPS system

[Bert Vermeulen <bert@biot.com>]

This is just enough system to boot the kernel with earlycon working.

Signed-off-by: Bert Vermeulen <bert@biot.com>
Signed-off-by: Sander Vanheule <sander@svanheule.net>
---
 arch/mips/Kconfig                       | 21 ++++++++++++++++++
 arch/mips/generic/Platform              |  1 +
 arch/mips/include/asm/realtek/ioremap.h | 29 +++++++++++++++++++++++++
 3 files changed, 51 insertions(+)
 create mode 100644 arch/mips/include/asm/realtek/ioremap.h

diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index 0a17bedf4f0d..0986d0c4405f 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -627,6 +627,27 @@ config RALINK
 	select ARCH_HAS_RESET_CONTROLLER
 	select RESET_CONTROLLER
 
+config MACH_REALTEK_RTL
+	bool "Realtek RTL838x/RTL839x based machines"
+	select MIPS_GENERIC
+	select DMA_NONCOHERENT
+	select IRQ_MIPS_CPU
+	select CSRC_R4K
+	select CEVT_R4K
+	select SYS_HAS_CPU_MIPS32_R1
+	select SYS_HAS_CPU_MIPS32_R2
+	select SYS_SUPPORTS_BIG_ENDIAN
+	select SYS_SUPPORTS_32BIT_KERNEL
+	select SYS_SUPPORTS_MIPS16
+	select SYS_SUPPORTS_MULTITHREADING
+	select SYS_SUPPORTS_VPE_LOADER
+	select SYS_HAS_EARLY_PRINTK
+	select SYS_HAS_EARLY_PRINTK_8250
+	select USE_GENERIC_EARLY_PRINTK_8250
+	select BOOT_RAW
+	select PINCTRL
+	select USE_OF
+
 config SGI_IP22
 	bool "SGI IP22 (Indy/Indigo2)"
 	select ARC_MEMORY
diff --git a/arch/mips/generic/Platform b/arch/mips/generic/Platform
index b871af16b5b6..5dff52295b0a 100644
--- a/arch/mips/generic/Platform
+++ b/arch/mips/generic/Platform
@@ -10,6 +10,7 @@
 
 # Note: order matters, keep the asm/mach-generic include last.
 cflags-$(CONFIG_MACH_INGENIC_SOC)	+= -I$(srctree)/arch/mips/include/asm/mach-ingenic
+cflags-$(CONFIG_MACH_REALTEK_RTL)	+= -I$(srctree)/arch/mips/include/asm/realtek
 cflags-$(CONFIG_MIPS_GENERIC)	+= -I$(srctree)/arch/mips/include/asm/mach-generic
 
 load-$(CONFIG_MIPS_GENERIC)	+= 0xffffffff80100000
diff --git a/arch/mips/include/asm/realtek/ioremap.h b/arch/mips/include/asm/realtek/ioremap.h
new file mode 100644
index 000000000000..ea51af023e26
--- /dev/null
+++ b/arch/mips/include/asm/realtek/ioremap.h
@@ -0,0 +1,29 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef _REALTEK_RTL_IOREMAP_H_
+#define _REALTEK_RTL_IOREMAP_H_
+
+static inline int is_rtl8380_internal_registers(phys_addr_t offset)
+{
+	/* IO Block */
+	if (offset >= 0xb8000000 && offset < 0xb9000000)
+		return 1;
+	/* Switch block */
+	if (offset >= 0xbb000000 && offset < 0xbc000000)
+		return 1;
+	return 0;
+}
+
+static inline void __iomem *plat_ioremap(phys_addr_t offset, unsigned long size,
+					 unsigned long flags)
+{
+	if (is_rtl8380_internal_registers(offset))
+		return (void __iomem *)offset;
+	return NULL;
+}
+
+static inline int plat_iounmap(const volatile void __iomem *addr)
+{
+	return is_rtl8380_internal_registers((unsigned long)addr);
+}
+
+#endif /* _REALTEK_RTL_IOREMAP_H_ */
-- 
2.25.1