Amlogic Meson6, Meson8, Meson8b and Meson8m2 embed an ARC core in the
Always-On (AO) power-domain. This is typically used for waking up the
ARM cores after system suspend.
The configuration is spread across three different registers:
- AO_REMAP_REG0 which must be programmed to zero, it's actual purpose
is unknown. There is a second remap register which is not used in the
vendor kernel (which served as reference for this driver).
- AO_CPU_CNTL is used to start and stop the ARC core.
- AO_SECURE_REG0 in the SECBUS2 register area with unknown purpose.
To boot the ARC core we also need to enable it's gate clock and trigger
a reset.
The actual code for this ARC core can come from an ELF binary, for
example by building the Zephyr RTOS for an ARC EM4 core and then taking
"zephyr.elf" as firmware. This executable does not have any "rsc table"
so we are skipping rproc_elf_load_rsc_table (rproc_ops.parse_fw) and
rproc_elf_find_loaded_rsc_table (rproc_ops.find_loaded_rsc_table).
Signed-off-by: Martin Blumenstingl <[email protected]>
---
drivers/remoteproc/Kconfig | 11 ++
drivers/remoteproc/Makefile | 1 +
drivers/remoteproc/meson_mx_ao_arc.c | 240 +++++++++++++++++++++++++++
3 files changed, 252 insertions(+)
create mode 100644 drivers/remoteproc/meson_mx_ao_arc.c
diff --git a/drivers/remoteproc/Kconfig b/drivers/remoteproc/Kconfig
index 9e7efe542f69..0e7fb91635fe 100644
--- a/drivers/remoteproc/Kconfig
+++ b/drivers/remoteproc/Kconfig
@@ -125,6 +125,17 @@ config KEYSTONE_REMOTEPROC
It's safe to say N here if you're not interested in the Keystone
DSPs or just want to use a bare minimum kernel.
+config MESON_MX_AO_ARC_REMOTEPROC
+ tristate "Amlogic Meson6/8/8b/8m2 AO ARC remote processor support"
+ depends on HAS_IOMEM
+ depends on (ARM && ARCH_MESON) || COMPILE_TEST
+ select GENERIC_ALLOCATOR
+ help
+ Say m or y here to have support for the AO ARC remote processor
+ on Amlogic Meson6/Meson8/Meson8b/Meson8m2 SoCs. This is
+ typically used for system suspend.
+ If unusre say N.
+
config PRU_REMOTEPROC
tristate "TI PRU remoteproc support"
depends on TI_PRUSS
diff --git a/drivers/remoteproc/Makefile b/drivers/remoteproc/Makefile
index bb26c9e4ef9c..ce1abeb30907 100644
--- a/drivers/remoteproc/Makefile
+++ b/drivers/remoteproc/Makefile
@@ -18,6 +18,7 @@ obj-$(CONFIG_OMAP_REMOTEPROC) += omap_remoteproc.o
obj-$(CONFIG_WKUP_M3_RPROC) += wkup_m3_rproc.o
obj-$(CONFIG_DA8XX_REMOTEPROC) += da8xx_remoteproc.o
obj-$(CONFIG_KEYSTONE_REMOTEPROC) += keystone_remoteproc.o
+obj-$(CONFIG_MESON_MX_AO_ARC_REMOTEPROC)+= meson_mx_ao_arc.o
obj-$(CONFIG_PRU_REMOTEPROC) += pru_rproc.o
obj-$(CONFIG_QCOM_PIL_INFO) += qcom_pil_info.o
obj-$(CONFIG_QCOM_RPROC_COMMON) += qcom_common.o
diff --git a/drivers/remoteproc/meson_mx_ao_arc.c b/drivers/remoteproc/meson_mx_ao_arc.c
new file mode 100644
index 000000000000..1deb03ca30f4
--- /dev/null
+++ b/drivers/remoteproc/meson_mx_ao_arc.c
@@ -0,0 +1,240 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2020 Martin Blumenstingl <[email protected]>
+ */
+
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/property.h>
+#include <linux/genalloc.h>
+#include <linux/io.h>
+#include <linux/ioport.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/remoteproc.h>
+#include <linux/reset.h>
+#include <linux/sizes.h>
+
+#include "remoteproc_internal.h"
+
+#define AO_REMAP_REG0 0x0
+#define AO_REMAP_REG1 0x4
+
+#define AO_CPU_CNTL 0x0
+ #define AO_CPU_CNTL_MEM_ADDR_UPPER GENMASK(28, 16)
+ #define AO_CPU_CNTL_HALT BIT(9)
+ #define AO_CPU_CNTL_UNKNONWN BIT(8)
+ #define AO_CPU_CNTL_RUN BIT(0)
+
+#define AO_CPU_STAT 0x4
+
+#define AO_SECURE_REG0 0x0
+ #define AO_SECURE_REG0_UNKNOWN GENMASK(23, 8)
+
+#define MESON_AO_RPROC_SRAM_USABLE_BITS GENMASK(31, 20)
+#define MESON_AO_RPROC_MEMORY_OFFSET 0x10000000
+
+struct meson_mx_ao_arc_rproc_priv {
+ void __iomem *remap_base;
+ void __iomem *cpu_base;
+ unsigned long sram_va;
+ phys_addr_t sram_pa;
+ size_t sram_size;
+ struct gen_pool *sram_pool;
+ struct reset_control *arc_reset;
+ struct clk *arc_pclk;
+ struct regmap *secbus2_regmap;
+};
+
+static int meson_mx_ao_arc_rproc_start(struct rproc *rproc)
+{
+ struct meson_mx_ao_arc_rproc_priv *priv = rproc->priv;
+ phys_addr_t phys_addr;
+ int ret;
+
+ ret = clk_prepare_enable(priv->arc_pclk);
+ if (ret)
+ return ret;
+
+ writel(0, priv->remap_base + AO_REMAP_REG0);
+ usleep_range(10, 100);
+
+ regmap_update_bits(priv->secbus2_regmap, AO_SECURE_REG0,
+ AO_SECURE_REG0_UNKNOWN, 0);
+
+ ret = reset_control_reset(priv->arc_reset);
+ if (ret) {
+ clk_disable_unprepare(priv->arc_pclk);
+ return ret;
+ }
+
+ usleep_range(10, 100);
+
+ /* convert from 0xd9000000 to 0xc9000000 as the vendor driver does */
+ phys_addr = priv->sram_pa - MESON_AO_RPROC_MEMORY_OFFSET;
+
+ writel(FIELD_PREP(AO_CPU_CNTL_MEM_ADDR_UPPER,
+ FIELD_GET(MESON_AO_RPROC_SRAM_USABLE_BITS, phys_addr)) |
+ AO_CPU_CNTL_UNKNONWN | AO_CPU_CNTL_RUN,
+ priv->cpu_base + AO_CPU_CNTL);
+ usleep_range(20, 200);
+
+ return 0;
+}
+
+static int meson_mx_ao_arc_rproc_stop(struct rproc *rproc)
+{
+ struct meson_mx_ao_arc_rproc_priv *priv = rproc->priv;
+
+ writel(AO_CPU_CNTL_HALT, priv->cpu_base + AO_CPU_CNTL);
+
+ clk_disable_unprepare(priv->arc_pclk);
+
+ return 0;
+}
+
+static void *meson_mx_ao_arc_rproc_da_to_va(struct rproc *rproc, u64 da,
+ size_t len)
+{
+ struct meson_mx_ao_arc_rproc_priv *priv = rproc->priv;
+
+ if ((da + len) >= priv->sram_size)
+ return NULL;
+
+ return (void *)priv->sram_va + da;
+}
+
+static struct rproc_ops meson_mx_ao_arc_rproc_ops = {
+ .start = meson_mx_ao_arc_rproc_start,
+ .stop = meson_mx_ao_arc_rproc_stop,
+ .da_to_va = meson_mx_ao_arc_rproc_da_to_va,
+ .get_boot_addr = rproc_elf_get_boot_addr,
+ .load = rproc_elf_load_segments,
+ .sanity_check = rproc_elf_sanity_check,
+};
+
+static int meson_mx_ao_arc_rproc_probe(struct platform_device *pdev)
+{
+ struct meson_mx_ao_arc_rproc_priv *priv;
+ struct platform_device *secbus2_pdev;
+ struct device *dev = &pdev->dev;
+ const char *fw_name;
+ struct rproc *rproc;
+ int ret;
+
+ ret = device_property_read_string(dev, "firmware-name", &fw_name);
+ if (ret)
+ fw_name = NULL;
+
+ rproc = devm_rproc_alloc(dev, "meson-mx-ao-arc",
+ &meson_mx_ao_arc_rproc_ops, fw_name,
+ sizeof(*priv));
+ if (!rproc)
+ return -ENOMEM;
+
+ rproc->has_iommu = false;
+ priv = rproc->priv;
+
+ priv->sram_pool = of_gen_pool_get(dev->of_node, "sram", 0);
+ if (!priv->sram_pool) {
+ dev_err(dev, "Could not get SRAM pool\n");
+ return -ENODEV;
+ }
+
+ priv->sram_size = gen_pool_avail(priv->sram_pool);
+
+ priv->sram_va = gen_pool_alloc(priv->sram_pool, priv->sram_size);
+ if (!priv->sram_va) {
+ dev_err(dev, "Could not alloc memory in SRAM pool\n");
+ return -ENOMEM;
+ }
+
+ priv->sram_pa = gen_pool_virt_to_phys(priv->sram_pool, priv->sram_va);
+ if (priv->sram_pa & ~MESON_AO_RPROC_SRAM_USABLE_BITS) {
+ dev_err(dev, "SRAM address contains unusable bits\n");
+ ret = -EINVAL;
+ goto err_free_genpool;
+ }
+
+ priv->secbus2_regmap = syscon_regmap_lookup_by_phandle(dev->of_node,
+ "amlogic,secbus2");
+ if (IS_ERR(priv->secbus2_regmap)) {
+ dev_err(dev, "Failed to find SECBUS2 regmap\n");
+ ret = PTR_ERR(priv->secbus2_regmap);
+ goto err_free_genpool;
+ }
+
+ priv->remap_base = devm_platform_ioremap_resource_byname(pdev, "remap");
+ if (IS_ERR(priv->remap_base)) {
+ ret = PTR_ERR(priv->remap_base);
+ goto err_free_genpool;
+ }
+
+ priv->cpu_base = devm_platform_ioremap_resource_byname(pdev, "cpu");
+ if (IS_ERR(priv->cpu_base)) {
+ ret = PTR_ERR(priv->cpu_base);
+ goto err_free_genpool;
+ }
+
+ priv->arc_reset = devm_reset_control_get_exclusive(dev, NULL);
+ if (IS_ERR(priv->arc_reset)) {
+ dev_err(dev, "Failed to get ARC reset\n");
+ ret = PTR_ERR(priv->arc_reset);
+ goto err_free_genpool;
+ }
+
+ priv->arc_pclk = devm_clk_get(dev, NULL);
+ if (IS_ERR(priv->arc_pclk)) {
+ dev_err(dev, "Failed to get the ARC PCLK\n");
+ ret = PTR_ERR(priv->arc_pclk);
+ goto err_free_genpool;
+ }
+
+ platform_set_drvdata(pdev, rproc);
+
+ ret = rproc_add(rproc);
+ if (ret)
+ goto err_free_genpool;
+
+ return 0;
+
+err_free_genpool:
+ gen_pool_free(priv->sram_pool, priv->sram_va, priv->sram_size);
+ return ret;
+}
+
+static int meson_mx_ao_arc_rproc_remove(struct platform_device *pdev)
+{
+ struct rproc *rproc = platform_get_drvdata(pdev);
+ struct meson_mx_ao_arc_rproc_priv *priv = rproc->priv;
+
+ rproc_del(rproc);
+ gen_pool_free(priv->sram_pool, priv->sram_va, priv->sram_size);
+
+ return 0;
+}
+
+static const struct of_device_id meson_mx_ao_arc_rproc_match[] = {
+ { .compatible = "amlogic,meson8-ao-arc" },
+ { .compatible = "amlogic,meson8b-ao-arc" },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, meson_mx_ao_arc_rproc_match);
+
+static struct platform_driver meson_mx_ao_arc_rproc_driver = {
+ .probe = meson_mx_ao_arc_rproc_probe,
+ .remove = meson_mx_ao_arc_rproc_remove,
+ .driver = {
+ .name = "meson-mx-ao-arc-rproc",
+ .of_match_table = of_match_ptr(meson_mx_ao_arc_rproc_match),
+ },
+};
+module_platform_driver(meson_mx_ao_arc_rproc_driver);
+
+MODULE_DESCRIPTION("Amlogic Meson6/8/8b/8m2 AO ARC remote processor driver");
+MODULE_AUTHOR("Martin Blumenstingl <[email protected]>");
+MODULE_LICENSE("GPL v2");
--
2.30.0
On Tue 29 Dec 19:27 CST 2020, Martin Blumenstingl wrote:
> Amlogic Meson6, Meson8, Meson8b and Meson8m2 embed an ARC core in the
> Always-On (AO) power-domain. This is typically used for waking up the
> ARM cores after system suspend.
>
> The configuration is spread across three different registers:
> - AO_REMAP_REG0 which must be programmed to zero, it's actual purpose
> is unknown. There is a second remap register which is not used in the
> vendor kernel (which served as reference for this driver).
> - AO_CPU_CNTL is used to start and stop the ARC core.
> - AO_SECURE_REG0 in the SECBUS2 register area with unknown purpose.
>
> To boot the ARC core we also need to enable it's gate clock and trigger
> a reset.
>
> The actual code for this ARC core can come from an ELF binary, for
> example by building the Zephyr RTOS for an ARC EM4 core and then taking
> "zephyr.elf" as firmware. This executable does not have any "rsc table"
> so we are skipping rproc_elf_load_rsc_table (rproc_ops.parse_fw) and
> rproc_elf_find_loaded_rsc_table (rproc_ops.find_loaded_rsc_table).
>
Thanks for the patch Martin, it looks really good. Just some minor
things as I expect a respin of the DT binding as well.
> Signed-off-by: Martin Blumenstingl <[email protected]>
> ---
> drivers/remoteproc/Kconfig | 11 ++
> drivers/remoteproc/Makefile | 1 +
> drivers/remoteproc/meson_mx_ao_arc.c | 240 +++++++++++++++++++++++++++
> 3 files changed, 252 insertions(+)
> create mode 100644 drivers/remoteproc/meson_mx_ao_arc.c
>
> diff --git a/drivers/remoteproc/Kconfig b/drivers/remoteproc/Kconfig
> index 9e7efe542f69..0e7fb91635fe 100644
> --- a/drivers/remoteproc/Kconfig
> +++ b/drivers/remoteproc/Kconfig
> @@ -125,6 +125,17 @@ config KEYSTONE_REMOTEPROC
> It's safe to say N here if you're not interested in the Keystone
> DSPs or just want to use a bare minimum kernel.
>
> +config MESON_MX_AO_ARC_REMOTEPROC
> + tristate "Amlogic Meson6/8/8b/8m2 AO ARC remote processor support"
> + depends on HAS_IOMEM
> + depends on (ARM && ARCH_MESON) || COMPILE_TEST
> + select GENERIC_ALLOCATOR
> + help
> + Say m or y here to have support for the AO ARC remote processor
> + on Amlogic Meson6/Meson8/Meson8b/Meson8m2 SoCs. This is
> + typically used for system suspend.
> + If unusre say N.
> +
> config PRU_REMOTEPROC
> tristate "TI PRU remoteproc support"
> depends on TI_PRUSS
> diff --git a/drivers/remoteproc/Makefile b/drivers/remoteproc/Makefile
> index bb26c9e4ef9c..ce1abeb30907 100644
> --- a/drivers/remoteproc/Makefile
> +++ b/drivers/remoteproc/Makefile
> @@ -18,6 +18,7 @@ obj-$(CONFIG_OMAP_REMOTEPROC) += omap_remoteproc.o
> obj-$(CONFIG_WKUP_M3_RPROC) += wkup_m3_rproc.o
> obj-$(CONFIG_DA8XX_REMOTEPROC) += da8xx_remoteproc.o
> obj-$(CONFIG_KEYSTONE_REMOTEPROC) += keystone_remoteproc.o
> +obj-$(CONFIG_MESON_MX_AO_ARC_REMOTEPROC)+= meson_mx_ao_arc.o
> obj-$(CONFIG_PRU_REMOTEPROC) += pru_rproc.o
> obj-$(CONFIG_QCOM_PIL_INFO) += qcom_pil_info.o
> obj-$(CONFIG_QCOM_RPROC_COMMON) += qcom_common.o
> diff --git a/drivers/remoteproc/meson_mx_ao_arc.c b/drivers/remoteproc/meson_mx_ao_arc.c
> new file mode 100644
> index 000000000000..1deb03ca30f4
> --- /dev/null
> +++ b/drivers/remoteproc/meson_mx_ao_arc.c
> @@ -0,0 +1,240 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * Copyright (C) 2020 Martin Blumenstingl <[email protected]>
> + */
> +
> +#include <linux/bitfield.h>
> +#include <linux/bitops.h>
> +#include <linux/clk.h>
> +#include <linux/delay.h>
> +#include <linux/property.h>
> +#include <linux/genalloc.h>
> +#include <linux/io.h>
> +#include <linux/ioport.h>
> +#include <linux/mfd/syscon.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +#include <linux/remoteproc.h>
> +#include <linux/reset.h>
> +#include <linux/sizes.h>
> +
> +#include "remoteproc_internal.h"
> +
> +#define AO_REMAP_REG0 0x0
> +#define AO_REMAP_REG1 0x4
> +
> +#define AO_CPU_CNTL 0x0
> + #define AO_CPU_CNTL_MEM_ADDR_UPPER GENMASK(28, 16)
> + #define AO_CPU_CNTL_HALT BIT(9)
> + #define AO_CPU_CNTL_UNKNONWN BIT(8)
> + #define AO_CPU_CNTL_RUN BIT(0)
> +
> +#define AO_CPU_STAT 0x4
> +
> +#define AO_SECURE_REG0 0x0
> + #define AO_SECURE_REG0_UNKNOWN GENMASK(23, 8)
> +
> +#define MESON_AO_RPROC_SRAM_USABLE_BITS GENMASK(31, 20)
> +#define MESON_AO_RPROC_MEMORY_OFFSET 0x10000000
> +
> +struct meson_mx_ao_arc_rproc_priv {
> + void __iomem *remap_base;
> + void __iomem *cpu_base;
> + unsigned long sram_va;
> + phys_addr_t sram_pa;
> + size_t sram_size;
> + struct gen_pool *sram_pool;
> + struct reset_control *arc_reset;
> + struct clk *arc_pclk;
> + struct regmap *secbus2_regmap;
> +};
> +
> +static int meson_mx_ao_arc_rproc_start(struct rproc *rproc)
> +{
> + struct meson_mx_ao_arc_rproc_priv *priv = rproc->priv;
> + phys_addr_t phys_addr;
> + int ret;
> +
> + ret = clk_prepare_enable(priv->arc_pclk);
> + if (ret)
> + return ret;
> +
> + writel(0, priv->remap_base + AO_REMAP_REG0);
> + usleep_range(10, 100);
> +
> + regmap_update_bits(priv->secbus2_regmap, AO_SECURE_REG0,
> + AO_SECURE_REG0_UNKNOWN, 0);
> +
> + ret = reset_control_reset(priv->arc_reset);
> + if (ret) {
> + clk_disable_unprepare(priv->arc_pclk);
> + return ret;
> + }
> +
> + usleep_range(10, 100);
> +
> + /* convert from 0xd9000000 to 0xc9000000 as the vendor driver does */
> + phys_addr = priv->sram_pa - MESON_AO_RPROC_MEMORY_OFFSET;
> +
> + writel(FIELD_PREP(AO_CPU_CNTL_MEM_ADDR_UPPER,
> + FIELD_GET(MESON_AO_RPROC_SRAM_USABLE_BITS, phys_addr)) |
This would be easier to read if you just masked phys_addr on the line
above.
> + AO_CPU_CNTL_UNKNONWN | AO_CPU_CNTL_RUN,
> + priv->cpu_base + AO_CPU_CNTL);
> + usleep_range(20, 200);
> +
> + return 0;
> +}
> +
> +static int meson_mx_ao_arc_rproc_stop(struct rproc *rproc)
> +{
> + struct meson_mx_ao_arc_rproc_priv *priv = rproc->priv;
> +
> + writel(AO_CPU_CNTL_HALT, priv->cpu_base + AO_CPU_CNTL);
> +
> + clk_disable_unprepare(priv->arc_pclk);
> +
> + return 0;
> +}
> +
> +static void *meson_mx_ao_arc_rproc_da_to_va(struct rproc *rproc, u64 da,
> + size_t len)
> +{
> + struct meson_mx_ao_arc_rproc_priv *priv = rproc->priv;
> +
> + if ((da + len) >= priv->sram_size)
> + return NULL;
> +
> + return (void *)priv->sram_va + da;
> +}
> +
> +static struct rproc_ops meson_mx_ao_arc_rproc_ops = {
> + .start = meson_mx_ao_arc_rproc_start,
> + .stop = meson_mx_ao_arc_rproc_stop,
> + .da_to_va = meson_mx_ao_arc_rproc_da_to_va,
> + .get_boot_addr = rproc_elf_get_boot_addr,
> + .load = rproc_elf_load_segments,
> + .sanity_check = rproc_elf_sanity_check,
> +};
> +
> +static int meson_mx_ao_arc_rproc_probe(struct platform_device *pdev)
> +{
> + struct meson_mx_ao_arc_rproc_priv *priv;
> + struct platform_device *secbus2_pdev;
> + struct device *dev = &pdev->dev;
> + const char *fw_name;
> + struct rproc *rproc;
> + int ret;
> +
> + ret = device_property_read_string(dev, "firmware-name", &fw_name);
> + if (ret)
> + fw_name = NULL;
I prefer relying on the fact that the read_string only touches fw_name
if it's about to return 0:
const char *fw_name = NULL;
device_property_read_string(dev, "firmware-name", &fw_name);
rproc =
But I won't force you to do this...
> +
> + rproc = devm_rproc_alloc(dev, "meson-mx-ao-arc",
> + &meson_mx_ao_arc_rproc_ops, fw_name,
> + sizeof(*priv));
> + if (!rproc)
> + return -ENOMEM;
> +
> + rproc->has_iommu = false;
> + priv = rproc->priv;
> +
> + priv->sram_pool = of_gen_pool_get(dev->of_node, "sram", 0);
> + if (!priv->sram_pool) {
> + dev_err(dev, "Could not get SRAM pool\n");
> + return -ENODEV;
> + }
> +
> + priv->sram_size = gen_pool_avail(priv->sram_pool);
> +
> + priv->sram_va = gen_pool_alloc(priv->sram_pool, priv->sram_size);
> + if (!priv->sram_va) {
> + dev_err(dev, "Could not alloc memory in SRAM pool\n");
> + return -ENOMEM;
> + }
> +
> + priv->sram_pa = gen_pool_virt_to_phys(priv->sram_pool, priv->sram_va);
> + if (priv->sram_pa & ~MESON_AO_RPROC_SRAM_USABLE_BITS) {
> + dev_err(dev, "SRAM address contains unusable bits\n");
> + ret = -EINVAL;
> + goto err_free_genpool;
> + }
> +
> + priv->secbus2_regmap = syscon_regmap_lookup_by_phandle(dev->of_node,
> + "amlogic,secbus2");
> + if (IS_ERR(priv->secbus2_regmap)) {
> + dev_err(dev, "Failed to find SECBUS2 regmap\n");
> + ret = PTR_ERR(priv->secbus2_regmap);
> + goto err_free_genpool;
> + }
> +
> + priv->remap_base = devm_platform_ioremap_resource_byname(pdev, "remap");
> + if (IS_ERR(priv->remap_base)) {
> + ret = PTR_ERR(priv->remap_base);
> + goto err_free_genpool;
> + }
> +
> + priv->cpu_base = devm_platform_ioremap_resource_byname(pdev, "cpu");
> + if (IS_ERR(priv->cpu_base)) {
> + ret = PTR_ERR(priv->cpu_base);
> + goto err_free_genpool;
> + }
> +
> + priv->arc_reset = devm_reset_control_get_exclusive(dev, NULL);
> + if (IS_ERR(priv->arc_reset)) {
> + dev_err(dev, "Failed to get ARC reset\n");
> + ret = PTR_ERR(priv->arc_reset);
> + goto err_free_genpool;
> + }
> +
> + priv->arc_pclk = devm_clk_get(dev, NULL);
> + if (IS_ERR(priv->arc_pclk)) {
> + dev_err(dev, "Failed to get the ARC PCLK\n");
> + ret = PTR_ERR(priv->arc_pclk);
> + goto err_free_genpool;
> + }
> +
> + platform_set_drvdata(pdev, rproc);
> +
> + ret = rproc_add(rproc);
> + if (ret)
> + goto err_free_genpool;
> +
> + return 0;
> +
> +err_free_genpool:
> + gen_pool_free(priv->sram_pool, priv->sram_va, priv->sram_size);
> + return ret;
> +}
> +
> +static int meson_mx_ao_arc_rproc_remove(struct platform_device *pdev)
> +{
> + struct rproc *rproc = platform_get_drvdata(pdev);
> + struct meson_mx_ao_arc_rproc_priv *priv = rproc->priv;
> +
> + rproc_del(rproc);
> + gen_pool_free(priv->sram_pool, priv->sram_va, priv->sram_size);
> +
> + return 0;
> +}
> +
> +static const struct of_device_id meson_mx_ao_arc_rproc_match[] = {
> + { .compatible = "amlogic,meson8-ao-arc" },
> + { .compatible = "amlogic,meson8b-ao-arc" },
> + { /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, meson_mx_ao_arc_rproc_match);
> +
> +static struct platform_driver meson_mx_ao_arc_rproc_driver = {
> + .probe = meson_mx_ao_arc_rproc_probe,
> + .remove = meson_mx_ao_arc_rproc_remove,
> + .driver = {
> + .name = "meson-mx-ao-arc-rproc",
> + .of_match_table = of_match_ptr(meson_mx_ao_arc_rproc_match),
Please drop the of_match_ptr(), because when the auto-builders get their
hands on this they fill figure out that without CONFIG_OF
meson_mx_ao_arc_rproc_match isn't referenced.
Regards,
Bjorn
> + },
> +};
> +module_platform_driver(meson_mx_ao_arc_rproc_driver);
> +
> +MODULE_DESCRIPTION("Amlogic Meson6/8/8b/8m2 AO ARC remote processor driver");
> +MODULE_AUTHOR("Martin Blumenstingl <[email protected]>");
> +MODULE_LICENSE("GPL v2");
> --
> 2.30.0
>
Hi Bjorn,
On Thu, Mar 18, 2021 at 3:51 AM Bjorn Andersson
<[email protected]> wrote:
>
> On Tue 29 Dec 19:27 CST 2020, Martin Blumenstingl wrote:
>
> > Amlogic Meson6, Meson8, Meson8b and Meson8m2 embed an ARC core in the
> > Always-On (AO) power-domain. This is typically used for waking up the
> > ARM cores after system suspend.
> >
> > The configuration is spread across three different registers:
> > - AO_REMAP_REG0 which must be programmed to zero, it's actual purpose
> > is unknown. There is a second remap register which is not used in the
> > vendor kernel (which served as reference for this driver).
> > - AO_CPU_CNTL is used to start and stop the ARC core.
> > - AO_SECURE_REG0 in the SECBUS2 register area with unknown purpose.
> >
> > To boot the ARC core we also need to enable it's gate clock and trigger
> > a reset.
> >
> > The actual code for this ARC core can come from an ELF binary, for
> > example by building the Zephyr RTOS for an ARC EM4 core and then taking
> > "zephyr.elf" as firmware. This executable does not have any "rsc table"
> > so we are skipping rproc_elf_load_rsc_table (rproc_ops.parse_fw) and
> > rproc_elf_find_loaded_rsc_table (rproc_ops.find_loaded_rsc_table).
> >
>
> Thanks for the patch Martin, it looks really good. Just some minor
> things as I expect a respin of the DT binding as well.
thank you for your comments.
I will send an updated series in the next few days and include all of
your suggested changes
since I sent this series (it's been a few days) I also got an update
from Amlogic so I know have better understanding of some (but
unfortunately not all) registers
so it'll be a bigger update. but don't worry: I'll include a changelog
Best regards,
Martin