Map the Global Control Registers (GCRs) provided by the MIPS Coherence Manager (CM) in preparation for using some of them in later patches.
Signed-off-by: Paul Burton paul.burton@imgtec.com ---
arch/mips/Kconfig | 16 ++++++++++++++++ arch/mips/cpu/Makefile | 2 ++ arch/mips/cpu/cm_init.S | 45 +++++++++++++++++++++++++++++++++++++++++++++ arch/mips/cpu/start.S | 6 ++++++ arch/mips/include/asm/cm.h | 19 +++++++++++++++++++ 5 files changed, 88 insertions(+) create mode 100644 arch/mips/cpu/cm_init.S create mode 100644 arch/mips/include/asm/cm.h
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig index 34eb404..732d129 100644 --- a/arch/mips/Kconfig +++ b/arch/mips/Kconfig @@ -307,6 +307,22 @@ config DYNAMIC_IO_PORT_BASE config MACH_CPU_INIT bool
+config MIPS_CM + bool + help + Select this if your system contains a MIPS Coherence Manager and you + wish U-Boot to configure it or make use of it to retrieve system + information such as cache configuration. + +config MIPS_CM_BASE + hex + default 0x1fbf8000 + help + The physical base address at which to map the MIPS Coherence Manager + Global Configuration Registers (GCRs). This should be set such that + the GCRs occupy a region of the physical address space which is + otherwise unused, or at minimum that software doesn't need to access. + endif
endmenu diff --git a/arch/mips/cpu/Makefile b/arch/mips/cpu/Makefile index fc6b455..429fd3a 100644 --- a/arch/mips/cpu/Makefile +++ b/arch/mips/cpu/Makefile @@ -7,3 +7,5 @@ extra-y = start.o obj-y += time.o obj-y += interrupts.o obj-y += cpu.o + +obj-$(CONFIG_MIPS_CM) += cm_init.o diff --git a/arch/mips/cpu/cm_init.S b/arch/mips/cpu/cm_init.S new file mode 100644 index 0000000..ddcaa49 --- /dev/null +++ b/arch/mips/cpu/cm_init.S @@ -0,0 +1,45 @@ +/* + * MIPS Coherence Manager (CM) Initialisation + * + * Copyright (c) 2016 Imagination Technologies Ltd. + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include <asm/addrspace.h> +#include <asm/asm.h> +#include <asm/cm.h> +#include <asm/mipsregs.h> +#include <asm/regdef.h> + +LEAF(mips_cm_map) + /* Config3 must exist for a CM to be present */ + mfc0 t0, CP0_CONFIG, 1 + bgez t0, 2f + mfc0 t0, CP0_CONFIG, 2 + bgez t0, 2f + + /* Check Config3.CMGCR to determine CM presence */ + mfc0 t0, CP0_CONFIG, 3 + and t0, t0, MIPS_CONF3_CMGCR + beqz t0, 2f + + /* Find the current physical GCR base address */ +1: MFC0 t0, CP0_CMGCRBASE + PTR_SLL t0, t0, 4 + + /* If the GCRs are where we want, we're done */ + PTR_LI t1, CONFIG_MIPS_CM_BASE + beq t0, t1, 2f + + /* Move the GCRs to our configured base address */ + PTR_LI t2, CKSEG1 + PTR_ADDU t0, t0, t2 + sw zero, GCR_BASE_UPPER(t0) + sw t1, GCR_BASE(t0) + + /* Re-check the GCR base */ + b 1b + +2: jr ra + END(mips_cm_map) diff --git a/arch/mips/cpu/start.S b/arch/mips/cpu/start.S index 6f1d219..c157d03 100644 --- a/arch/mips/cpu/start.S +++ b/arch/mips/cpu/start.S @@ -141,6 +141,12 @@ reset: 1: PTR_L gp, 0(ra)
+#ifdef CONFIG_MIPS_CM + PTR_LA t9, mips_cm_map + jalr t9 + nop +#endif + #ifndef CONFIG_SKIP_LOWLEVEL_INIT # ifdef CONFIG_SYS_MIPS_CACHE_INIT_RAM_LOAD /* Initialize any external memory */ diff --git a/arch/mips/include/asm/cm.h b/arch/mips/include/asm/cm.h new file mode 100644 index 0000000..0261733 --- /dev/null +++ b/arch/mips/include/asm/cm.h @@ -0,0 +1,19 @@ +/* + * MIPS Coherence Manager (CM) Register Definitions + * + * Copyright (c) 2016 Imagination Technologies Ltd. + * + * SPDX-License-Identifier: GPL-2.0+ + */ +#ifndef __MIPS_ASM_CM_H__ +#define __MIPS_ASM_CM_H__ + +/* Global Control Register (GCR) offsets */ +#define GCR_BASE 0x0008 +#define GCR_BASE_UPPER 0x000c +#define GCR_REV 0x0030 + +/* GCR_REV CM versions */ +#define GCR_REV_CM3 0x0800 + +#endif /* __MIPS_ASM_CM_H__ */