[U-Boot] [PATCH v5] mx6: add support of multi-processor command

Gabriel Huau
2014-07-12T22:31:04Z

This allows u-boot to load different OS or Bare Metal application on the
different cores of the i.MX6DQ.
For example: we can run Android on cpu0 and a RT OS like QNX/FreeRTOS on cpu1.

Signed-off-by: Gabriel Huau <contact@huau-gabriel.fr>
---
Changes for v2:
- Add a commit log message to explain the purpose of this patch
Changes for v3:
- Remove unnecessary check for unsigned values when they are negative
Changes for v4:
- Add CONFIG_MP to the common mx6 configuration
- Get the number of CPUs dynamically instead of using a macro
Changes for v5:
- Rebase on the last update of the tree (conflicts solved)
- Add a dummy header to solve build issue regarding the common/board_f.c

arch/arm/cpu/armv7/mx6/Makefile | 1 +
arch/arm/cpu/armv7/mx6/mp.c | 134 ++++++++++++++++++++++++++++++
arch/arm/cpu/armv7/mx6/soc.c | 6 ++
arch/arm/include/asm/arch-mx6/imx-regs.h | 13 +++
arch/arm/include/asm/arch-mx6/sys_proto.h | 1 +
arch/arm/include/asm/mp.h | 11 +++
include/configs/mx6_common.h | 2 +
7 files changed, 168 insertions(+)
create mode 100644 arch/arm/cpu/armv7/mx6/mp.c
create mode 100644 arch/arm/include/asm/mp.h

diff --git a/arch/arm/cpu/armv7/mx6/Makefile b/arch/arm/cpu/armv7/mx6/Makefile
index 6dc9f8e..bf6effc 100644
--- a/arch/arm/cpu/armv7/mx6/Makefile
+++ b/arch/arm/cpu/armv7/mx6/Makefile
@@ -10,3 +10,4 @@
obj-y := soc.o clock.o
obj-$(CONFIG_SPL_BUILD) += ddr.o
obj-$(CONFIG_SECURE_BOOT) += hab.o
+obj-$(CONFIG_MP) += mp.o
diff --git a/arch/arm/cpu/armv7/mx6/mp.c b/arch/arm/cpu/armv7/mx6/mp.c
new file mode 100644
index 0000000..85003d3
--- /dev/null
+++ b/arch/arm/cpu/armv7/mx6/mp.c
@@ -0,0 +1,134 @@
+/*
+ * (C) Copyright 2014
+ * Gabriel Huau <contact@huau-gabriel.fr>
+ *
+ * (C) Copyright 2009 Freescale Semiconductor, Inc.
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <asm/errno.h>
+#include <asm/arch/sys_proto.h>
+#include <asm/arch/imx-regs.h>
+
+int cpu_reset(int nr)
+{
+ uint32_t reg;
+ struct src *src = (struct src *)SRC_BASE_ADDR;
+
+ reg = __raw_readl(&src->scr);
+
+ switch (nr) {
+ case 1:
+ reg |= SRC_SCR_CORE_1_RESET_MASK;
+ break;
+
+ case 2:
+ reg |= SRC_SCR_CORE_2_RESET_MASK;
+ break;
+
+ case 3:
+ reg |= SRC_SCR_CORE_3_RESET_MASK;
+ break;
+ }
+
+ /* Software reset of the CPU N */
+ __raw_writel(reg, &src->scr);
+
+ return 0;
+}
+
+int cpu_status(int nr)
+{
+ uint32_t reg;
+ struct src *src = (struct src *)SRC_BASE_ADDR;
+
+ reg = __raw_readl(&src->scr);
+
+ switch (nr) {
+ case 1:
+ printf("core 1: %d\n", !!(reg & SRC_SCR_CORE_1_ENABLE_MASK));
+ break;
+
+ case 2:
+ printf("core 2: %d\n", !!(reg & SRC_SCR_CORE_2_ENABLE_MASK));
+ break;
+
+ case 3:
+ printf("core 3: %d\n", !!(reg & SRC_SCR_CORE_3_ENABLE_MASK));
+ break;
+ }
+
+ return 0;
+}
+
+int cpu_release(int nr, int argc, char *const argv[])
+{
+ uint32_t reg;
+ struct src *src = (struct src *)SRC_BASE_ADDR;
+ uint32_t boot_addr;
+
+ boot_addr = simple_strtoul(argv[0], NULL, 16);
+ reg = __raw_readl(&src->scr);
+
+ switch (nr) {
+ case 1:
+ __raw_writel(boot_addr, &src->gpr3);
+ reg |= SRC_SCR_CORE_1_ENABLE_MASK;
+ break;
+
+ case 2:
+ __raw_writel(boot_addr, &src->gpr5);
+ reg |= SRC_SCR_CORE_2_ENABLE_MASK;
+ break;
+
+ case 3:
+ __raw_writel(boot_addr, &src->gpr7);
+ reg |= SRC_SCR_CORE_3_ENABLE_MASK;
+ break;
+ }
+
+ /* CPU N is ready to start */
+ __raw_writel(reg, &src->scr);
+
+ return 0;
+}
+
+int is_core_valid(unsigned int core)
+{
+ uint32_t nr_cores = get_nr_cpus();
+
+ if (core > nr_cores)
+ return 0;
+
+ return 1;
+}
+
+int cpu_disable(int nr)
+{
+ uint32_t reg;
+ struct src *src = (struct src *)SRC_BASE_ADDR;
+
+ reg = __raw_readl(&src->scr);
+
+ switch (nr) {
+ case 1:
+ reg &= ~SRC_SCR_CORE_1_ENABLE_MASK;
+ break;
+
+ case 2:
+ reg &= ~SRC_SCR_CORE_2_ENABLE_MASK;
+ break;
+
+ case 3:
+ reg &= ~SRC_SCR_CORE_3_ENABLE_MASK;
+ break;
+ }
+
+ /* Disable the CPU N */
+ __raw_writel(reg, &src->scr);
+
+ return 0;
+}
diff --git a/arch/arm/cpu/armv7/mx6/soc.c b/arch/arm/cpu/armv7/mx6/soc.c
index f20bdeb..19429b2 100644
--- a/arch/arm/cpu/armv7/mx6/soc.c
+++ b/arch/arm/cpu/armv7/mx6/soc.c
@@ -35,6 +35,12 @@ struct scu_regs {
u32 fpga_rev;
};

+u32 get_nr_cpus(void)
+{
+ struct scu_regs *scu = (struct scu_regs *)SCU_BASE_ADDR;
+ return readl(&scu->config) & 3;
+}
+
u32 get_cpu_rev(void)
{
struct anatop_regs *anatop = (struct anatop_regs *)ANATOP_BASE_ADDR;
diff --git a/arch/arm/include/asm/arch-mx6/imx-regs.h b/arch/arm/include/asm/arch-mx6/imx-regs.h
index a69a753..a90cbe9 100644
--- a/arch/arm/include/asm/arch-mx6/imx-regs.h
+++ b/arch/arm/include/asm/arch-mx6/imx-regs.h
@@ -227,6 +227,19 @@

extern void imx_get_mac_from_fuse(int dev_id, unsigned char *mac);

+#define SRC_SCR_CORE_1_RESET_OFFSET 14
+#define SRC_SCR_CORE_1_RESET_MASK (1<<SRC_SCR_CORE_1_RESET_OFFSET)
+#define SRC_SCR_CORE_2_RESET_OFFSET 15
+#define SRC_SCR_CORE_2_RESET_MASK (1<<SRC_SCR_CORE_2_RESET_OFFSET)
+#define SRC_SCR_CORE_3_RESET_OFFSET 16
+#define SRC_SCR_CORE_3_RESET_MASK (1<<SRC_SCR_CORE_3_RESET_OFFSET)
+#define SRC_SCR_CORE_1_ENABLE_OFFSET 22
+#define SRC_SCR_CORE_1_ENABLE_MASK (1<<SRC_SCR_CORE_1_ENABLE_OFFSET)
+#define SRC_SCR_CORE_2_ENABLE_OFFSET 23
+#define SRC_SCR_CORE_2_ENABLE_MASK (1<<SRC_SCR_CORE_2_ENABLE_OFFSET)
+#define SRC_SCR_CORE_3_ENABLE_OFFSET 24
+#define SRC_SCR_CORE_3_ENABLE_MASK (1<<SRC_SCR_CORE_3_ENABLE_OFFSET)
+
/* System Reset Controller (SRC) */
struct src {
u32 scr;
diff --git a/arch/arm/include/asm/arch-mx6/sys_proto.h b/arch/arm/include/asm/arch-mx6/sys_proto.h
index 42d30f5..7cbc133 100644
--- a/arch/arm/include/asm/arch-mx6/sys_proto.h
+++ b/arch/arm/include/asm/arch-mx6/sys_proto.h
@@ -14,6 +14,7 @@
#define soc_rev() (get_cpu_rev() & 0xFF)
#define is_soc_rev(rev) (soc_rev() - rev)

+#define is_soc_rev(rev) ((get_cpu_rev() & 0xFF) - rev)
u32 get_cpu_rev(void);

/* returns MXC_CPU_ value */
diff --git a/arch/arm/include/asm/mp.h b/arch/arm/include/asm/mp.h
new file mode 100644
index 0000000..8cf8d88
--- /dev/null
+++ b/arch/arm/include/asm/mp.h
@@ -0,0 +1,11 @@
+/*
+ * (C) Copyright 2014
+ * Gabriel Huau <contact@huau-gabriel.fr>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#ifndef _ASM_MP_H_
+#define _ASM_MP_H_
+
+#endif
diff --git a/include/configs/mx6_common.h b/include/configs/mx6_common.h
index e4a5cc5..135a3f5 100644
--- a/include/configs/mx6_common.h
+++ b/include/configs/mx6_common.h
@@ -28,4 +28,6 @@
#define CONFIG_SYS_PL310_BASE L2_PL310_BASE
#endif

+#define CONFIG_MP
+
#endif
--
2.0.0