On Thu, Sep 12, 2024 at 2:59 AM Simon Glass sjg@chromium.org wrote:
Hi Patrick,
On Wed, 11 Sept 2024 at 00:31, Patrick Rudolph patrick.rudolph@9elements.com wrote:
When ACPI is enabled over FDT the APs cannot be brought out of reset by the OS using the "FDT spin-table" mechanism, as no FDT is provided to the OS. The APs must be released out of reset in u-boot and then brought up in an ACPI compliant fashion.
When ARMV8_MULTIENTRY is specified the APs are released from reset and will enter U-Boot after it has been relocated as well.
By default ARMV8_MULTIENTRY is not selected, keeping existing behaviour.
TEST: All APs enter U-Boot when run on qemu-system-aarch64 and on real hardware.
Signed-off-by: Patrick Rudolph patrick.rudolph@9elements.com Cc: Matthias Brugger mbrugger@suse.com Cc: Peter Robinson pbrobinson@gmail.com Cc: Tom Rini trini@konsulko.com
Changelog v2:
- Drop CPU code from board
- Add CPU driver to release APs from reset
arch/arm/Kconfig | 1 + arch/arm/mach-bcm283x/Kconfig | 2 + arch/arm/mach-bcm283x/init.c | 8 ++ drivers/cpu/Makefile | 1 + drivers/cpu/bcm283x_cpu.c | 194 ++++++++++++++++++++++++++++++++++ 5 files changed, 206 insertions(+) create mode 100644 drivers/cpu/bcm283x_cpu.c
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 588e293bf2..17cd3d44b6 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -644,6 +644,7 @@ config ARCH_ORION5X
config ARCH_BCM283X bool "Broadcom BCM283X family"
select CPU select DM select DM_GPIO select DM_SERIALdiff --git a/arch/arm/mach-bcm283x/Kconfig b/arch/arm/mach-bcm283x/Kconfig index b3287ce8bc..de783aa8f5 100644 --- a/arch/arm/mach-bcm283x/Kconfig +++ b/arch/arm/mach-bcm283x/Kconfig @@ -12,6 +12,7 @@ config BCM2836 config BCM2837 bool "Broadcom BCM2837 SoC support" depends on ARCH_BCM283X
select ARCH_EARLY_INIT_Rconfig BCM2837_32B bool "Broadcom BCM2837 SoC 32-bit support" @@ -29,6 +30,7 @@ config BCM2837_64B config BCM2711 bool "Broadcom BCM2711 SoC support" depends on ARCH_BCM283X
select ARCH_EARLY_INIT_Rconfig BCM2711_32B bool "Broadcom BCM2711 SoC 32-bit support" diff --git a/arch/arm/mach-bcm283x/init.c b/arch/arm/mach-bcm283x/init.c index 7a1de22e0a..e6946c6e94 100644 --- a/arch/arm/mach-bcm283x/init.c +++ b/arch/arm/mach-bcm283x/init.c @@ -9,6 +9,7 @@ #include <cpu_func.h> #include <init.h> #include <dm/device.h> +#include <dm/uclass.h> #include <fdt_support.h> #include <asm/global_data.h>
@@ -199,7 +200,14 @@ int mach_cpu_init(void) "brcm,bcm2712-pm"); if (offset > soc) rpi_wdog_base = fdt_get_base_address(gd->fdt_blob, offset);
return 0;+}
+int arch_early_init_r(void) +{
struct udevice *dev;uclass_first_device(UCLASS_CPU, &dev);blank line before final return
return 0;This is fine, but you should check for an error, right?
Also there is print_cpuinfo() which should be called if CONFIG_CPU is enabled...it is a little later in the init sequence. Is it too late for your purposes?
print_cpuinfo() is called before relocation, so cannot be used to invoke the CPU driver. It would release the secondary CPUs and they would keep spinning in the non relocated U-Boot code.
}
diff --git a/drivers/cpu/Makefile b/drivers/cpu/Makefile index 773395693a..5230408cc0 100644 --- a/drivers/cpu/Makefile +++ b/drivers/cpu/Makefile @@ -7,6 +7,7 @@ obj-$(CONFIG_CPU) += cpu-uclass.o
+obj-$(CONFIG_ARCH_BCM283X) += bcm283x_cpu.o obj-$(CONFIG_ARCH_BMIPS) += bmips_cpu.o obj-$(CONFIG_ARCH_IMX8) += imx8_cpu.o obj-$(CONFIG_ARCH_AT91) += at91_cpu.o diff --git a/drivers/cpu/bcm283x_cpu.c b/drivers/cpu/bcm283x_cpu.c new file mode 100644 index 0000000000..11dd3008cc --- /dev/null +++ b/drivers/cpu/bcm283x_cpu.c @@ -0,0 +1,194 @@ +// SPDX-License-Identifier: GPL-2.0+ +/*
- Copyright 2024 9elements GmbH
- */
+#include <asm/cache.h> +#include <asm/io.h> +#include <asm/global_data.h> +#include <asm/system.h> +#include <asm/armv8/cpu.h> +#include <asm-generic/sections.h> +#include <cpu.h> +#include <cpu_func.h> +#include <dm.h> +#include <fdt_support.h> +#include <linux/bitops.h> +#include <linux/clk-provider.h> +#include <linux/delay.h>
+DECLARE_GLOBAL_DATA_PTR;
+static int cpu_bcm_get_desc(const struct udevice *dev, char *buf, int size) +{
struct cpu_plat *plat = dev_get_parent_plat(dev);const char *name;int ret;if (size < 32)return -ENOSPC;if (device_is_compatible(dev, "arm,cortex-a53"))name = "A53";else if (device_is_compatible(dev, "arm,cortex-a72"))name = "A72";elsename = "?";ret = snprintf(buf, size, "Broadcom Cortex-%s at %u MHz",name, plat->timebase_freq);snprintf(buf + ret, size - ret, "\n");Can you put the \n at the end of the previous statement?
return 0;+}
+static int cpu_bcm_get_info(const struct udevice *dev, struct cpu_info *info) +{
struct cpu_plat *plat = dev_get_parent_plat(dev);info->cpu_freq = plat->timebase_freq * 1000;info->features = BIT(CPU_FEAT_L1_CACHE) | BIT(CPU_FEAT_MMU);blank line
return 0;+}
+static int cpu_bcm_get_count(const struct udevice *dev) +{
ofnode node;int num = 0;ofnode_for_each_subnode(node, dev_ofnode(dev->parent)) {const char *device_type;if (!ofnode_is_enabled(node))continue;device_type = ofnode_read_string(node, "device_type");if (!device_type)continue;if (!strcmp(device_type, "cpu"))num++;}This should really be done in the of_to_plat() method. Store it somewhere so this function can just return it.
Will add it.
return num;+}
+static int cpu_bcm_get_vendor(const struct udevice *dev, char *buf, int size) +{
snprintf(buf, size, "Broadcom");blank line here (please fix globally)
return 0;+}
+#ifdef CONFIG_ARM64 +static int cpu_bcm_is_current(struct udevice *dev) +{
struct cpu_plat *plat = dev_get_parent_plat(dev);if (plat->cpu_id == (read_mpidr() & 0xffff))return 1;return 0;+} +#endif
+static int bcm_cpu_on(struct udevice *dev)
What does this do? Does it turn on the CPU? Perhaps add a comment?
Also, please return 0 for success, -ve error code otherwise
+{
ofnode node = dev_ofnode(dev);uintptr_t *start_address;ulong start_address
u64 release_addr64;release_addr
const char *prop;if (!ofnode_is_enabled(node))return 0;Hmm, but if it isn't enabled, how would this device be bound?
prop = ofnode_read_string(node, "enable-method");if (!prop || strcmp(prop, "spin-table"))return 1;release_addr64 = ofnode_read_u64_default(node, "cpu-release-addr", ~0ULL);if (release_addr64 == ~0ULL)return 1;if (ofnode_read_u64(node, "cpu-release-addr"), &release_addr)) return -EINVAL;
start_address = map_physmem(release_addr64, sizeof(uintptr_t), MAP_NOCACHE);/* Point to U-Boot start */*start_address = (uintptr_t)_start;flush_dcache_all();dcache always enabled? Which is fine...just asking
/* Send an event to wake up the secondary CPU. */asm("dsb ishst\n""sev");udelay(10000);unmap_physmem(start_address, MAP_NOCACHE);return 0;+}
+static int bcm_init(struct udevice *dev) +{
int ret = 0;/* The armstub holds the secondary CPUs in a spinloop. When/*
- The
* ARMV8_MULTIENTRY is enabled release the secondary CPUs and* let them enter U-Boot as well.*/if (CONFIG_IS_ENABLED(ARMV8_MULTIENTRY))ret = bcm_cpu_on(dev);return ret;More U-Boot-esk:
if (CONFIG_IS_ENABLED(ARMV8_MULTIENTRY)) { int ret; ret = bcm_cpu_on(dev); if (ret) return ret; }return 0; }
+}
+static const struct cpu_ops cpu_bcm_ops = {
.get_desc = cpu_bcm_get_desc,.get_info = cpu_bcm_get_info,.get_count = cpu_bcm_get_count,.get_vendor = cpu_bcm_get_vendor,+#ifdef CONFIG_ARM64
Can just check this in the function, to avoid an #ifdef
.is_current = cpu_bcm_is_current,+#endif +};
+static const struct udevice_id cpu_bcm_ids[] = {
{ .compatible = "arm,cortex-a53" }, /* RPi 3 */{ .compatible = "arm,cortex-a72" }, /* RPi 4 */{ }+};
+static int cpu_bcm_bind(struct udevice *dev) +{
struct cpu_plat *plat = dev_get_parent_plat(dev);plat->cpu_id = dev_read_addr(dev);You should not bring up the CPUs so early. The bind() method is just for binding. Can this move to probe() ?
This took me a while. The main issue here was that uclass_first_device(UCLASS_CPU, &dev); only probes the first CPU, but not the others. That's why I used bind() in the first place.
return bcm_init(dev);+}
+static int bcm_cpu_probe(struct udevice *dev) +{
struct cpu_plat *plat = dev_get_parent_plat(dev);struct clk clk;int ret;/* Get a clock if it exists */ret = clk_get_by_index(dev, 0, &clk);if (!ret) {ret = clk_enable(&clk);if (ret && (ret != -ENOSYS || ret != -EOPNOTSUPP))return ret;ret = clk_get_rate(&clk);if (!IS_ERR_VALUE(ret))plat->timebase_freq = ret;If you get an error, you must return it
}return ret;+}
+U_BOOT_DRIVER(cpu_bcm_drv) = {
.name = "bcm283x_cpu",.id = UCLASS_CPU,.of_match = cpu_bcm_ids,.ops = &cpu_bcm_ops,.probe = bcm_cpu_probe,.bind = cpu_bcm_bind,.flags = 0,+};
2.46.0
Regards, Simon