diff options
Diffstat (limited to 'drivers/sm/meson-sm.c')
| -rw-r--r-- | drivers/sm/meson-sm.c | 198 |
1 files changed, 198 insertions, 0 deletions
diff --git a/drivers/sm/meson-sm.c b/drivers/sm/meson-sm.c new file mode 100644 index 0000000000..25adaf4560 --- /dev/null +++ b/drivers/sm/meson-sm.c @@ -0,0 +1,198 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (c) 2023 SberDevices, Inc. + * + * Author: Alexey Romanov <avromanov@salutedevices.com> + */ + +#include <common.h> +#include <dm.h> +#include <regmap.h> +#include <sm.h> +#include <sm-uclass.h> +#include <stdlib.h> +#include <syscon.h> +#include <asm/ptrace.h> +#include <asm/system.h> +#include <meson/sm.h> +#include <linux/bitfield.h> +#include <linux/err.h> +#include <linux/sizes.h> + +struct meson_sm_cmd { + u32 smc_id; +}; + +#define SET_CMD(index, id) \ + [index] = { \ + .smc_id = (id), \ + } + +struct meson_sm_data { + u32 cmd_get_shmem_in; + u32 cmd_get_shmem_out; + unsigned int shmem_size; + struct meson_sm_cmd cmd[]; +}; + +struct meson_sm_priv { + void *sm_shmem_in; + void *sm_shmem_out; + const struct meson_sm_data *data; +}; + +static unsigned long __meson_sm_call(u32 cmd, const struct pt_regs *args) +{ + struct pt_regs r = *args; + + r.regs[0] = cmd; + smc_call(&r); + + return r.regs[0]; +}; + +static u32 meson_sm_get_cmd(const struct meson_sm_data *data, + u32 cmd_index) +{ + struct meson_sm_cmd cmd; + + if (cmd_index >= MESON_SMC_CMD_COUNT) + return 0; + + cmd = data->cmd[cmd_index]; + return cmd.smc_id; +} + +static int meson_sm_call(struct udevice *dev, u32 cmd_index, s32 *retval, + struct pt_regs *args) +{ + struct meson_sm_priv *priv = dev_get_priv(dev); + u32 cmd, ret; + + cmd = meson_sm_get_cmd(priv->data, cmd_index); + if (!cmd) + return -ENOENT; + + ret = __meson_sm_call(cmd, args); + if (retval) + *retval = ret; + + return 0; +} + +static int meson_sm_call_read(struct udevice *dev, void *buffer, size_t size, + u32 cmd_index, struct pt_regs *args) +{ + struct meson_sm_priv *priv = dev_get_priv(dev); + s32 nbytes; + int ret; + + if (!buffer || size > priv->data->shmem_size) + return -EINVAL; + + ret = meson_sm_call(dev, cmd_index, &nbytes, args); + if (ret) + return ret; + + if (nbytes < 0 || nbytes > size) + return -ENOBUFS; + + /* In some cases (for example GET_CHIP_ID command), + * SMC doesn't return the number of bytes read, even + * though the bytes were actually read into sm_shmem_out. + * So this check is needed. + */ + ret = nbytes; + if (!nbytes) + nbytes = size; + + memcpy(buffer, priv->sm_shmem_out, nbytes); + + return ret; +} + +static int meson_sm_call_write(struct udevice *dev, void *buffer, size_t size, + u32 cmd_index, struct pt_regs *args) +{ + struct meson_sm_priv *priv = dev_get_priv(dev); + s32 nbytes; + int ret; + + if (!buffer || size > priv->data->shmem_size) + return -EINVAL; + + memcpy(priv->sm_shmem_in, buffer, size); + + ret = meson_sm_call(dev, cmd_index, &nbytes, args); + if (ret) + return ret; + + if (nbytes <= 0 || nbytes > size) + return -EIO; + + return nbytes; +} + +static int meson_sm_probe(struct udevice *dev) +{ + struct meson_sm_priv *priv = dev_get_priv(dev); + struct pt_regs regs = { 0 }; + + priv->data = (struct meson_sm_data *)dev_get_driver_data(dev); + if (!priv->data) + return -EINVAL; + + priv->sm_shmem_in = + (void *)__meson_sm_call(priv->data->cmd_get_shmem_in, ®s); + + if (!priv->sm_shmem_in) + return -ENOMEM; + + priv->sm_shmem_out = + (void *)__meson_sm_call(priv->data->cmd_get_shmem_out, ®s); + + if (!priv->sm_shmem_out) + return -ENOMEM; + + pr_debug("meson sm driver probed\n" + "shmem_in addr: 0x%p, shmem_out addr: 0x%p\n", + priv->sm_shmem_in, + priv->sm_shmem_out); + + return 0; +} + +static const struct meson_sm_data meson_sm_gxbb_data = { + .cmd_get_shmem_in = 0x82000020, + .cmd_get_shmem_out = 0x82000021, + .shmem_size = SZ_4K, + .cmd = { + SET_CMD(MESON_SMC_CMD_EFUSE_READ, 0x82000030), + SET_CMD(MESON_SMC_CMD_EFUSE_WRITE, 0x82000031), + SET_CMD(MESON_SMC_CMD_CHIP_ID_GET, 0x82000044), + SET_CMD(MESON_SMC_CMD_PWRDM_SET, 0x82000093), + }, +}; + +static const struct udevice_id meson_sm_ids[] = { + { + .compatible = "amlogic,meson-gxbb-sm", + .data = (ulong)&meson_sm_gxbb_data, + }, + { } +}; + +static const struct sm_ops sm_ops = { + .sm_call = meson_sm_call, + .sm_call_read = meson_sm_call_read, + .sm_call_write = meson_sm_call_write, +}; + +U_BOOT_DRIVER(meson_sm) = { + .name = "meson_sm", + .id = UCLASS_SM, + .of_match = meson_sm_ids, + .probe = meson_sm_probe, + .priv_auto = sizeof(struct meson_sm_priv), + .ops = &sm_ops, +}; |