> -----Original Message-----
> From: ChiaWei Wang <chiawei_w...@aspeedtech.com>
> Sent: Tuesday, September 8, 2020 3:21 PM
> To: Ryan Chen <ryan_c...@aspeedtech.com>; max...@google.com;
> u-boot@lists.denx.de
> Cc: BMC-SW <bmc...@aspeedtech.com>
> Subject: [PATCH 1/2] reset: ast2500: Use SCU for reset control
>
> The System Control Unit (SCU) controller of Aspeed SoCs provides the reset
> control for each peripheral.
>
> This patch refactors the reset method to leverage the SCU reset control. Thus
> the driver dependency on watchdog including dedicated WDT API and reset
> flag encoding can be eliminated.
>
> The Kconfig description is also updated accordingly.
>
> Signed-off-by: Chia-Wei, Wang <chiawei_w...@aspeedtech.com>
Reviewed-by: Ryan Chen <ryan_c...@aspeedtech.com>
> ---
> arch/arm/dts/ast2500-u-boot.dtsi | 7 +-
> drivers/reset/Kconfig | 9 +--
> drivers/reset/ast2500-reset.c | 97 ++++++++++++-----------
> include/dt-bindings/reset/ast2500-reset.h | 73 +++++++++--------
> 4 files changed, 97 insertions(+), 89 deletions(-)
>
> diff --git a/arch/arm/dts/ast2500-u-boot.dtsi
> b/arch/arm/dts/ast2500-u-boot.dtsi
> index 8ac4215745..ca4aac2159 100644
> --- a/arch/arm/dts/ast2500-u-boot.dtsi
> +++ b/arch/arm/dts/ast2500-u-boot.dtsi
> @@ -15,7 +15,6 @@
> rst: reset-controller {
> u-boot,dm-pre-reloc;
> compatible = "aspeed,ast2500-reset";
> - aspeed,wdt = <&wdt1>;
> #reset-cells = <1>;
> };
>
> @@ -26,7 +25,7 @@
> 0x1e6e0200 0x1d4 >;
> #reset-cells = <1>;
> clocks = <&scu PLL_MPLL>;
> - resets = <&rst AST_RESET_SDRAM>;
> + resets = <&rst ASPEED_RESET_SDRAM>;
> };
>
> ahb {
> @@ -40,7 +39,7 @@
> reg = <0x1e740100>;
> #reset-cells = <1>;
> clocks = <&scu BCLK_SDCLK>;
> - resets = <&rst AST_RESET_SDIO>;
> + resets = <&rst ASPEED_RESET_SDIO>;
> };
>
> sdhci1: sdhci@1e740200 {
> @@ -48,7 +47,7 @@
> reg = <0x1e740200>;
> #reset-cells = <1>;
> clocks = <&scu BCLK_SDCLK>;
> - resets = <&rst AST_RESET_SDIO>;
> + resets = <&rst ASPEED_RESET_SDIO>;
> };
> };
>
> diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig index
> 253902ff57..796aa267c5 100644
> --- a/drivers/reset/Kconfig
> +++ b/drivers/reset/Kconfig
> @@ -74,13 +74,12 @@ config RESET_UNIPHIER
>
> config AST2500_RESET
> bool "Reset controller driver for AST2500 SoCs"
> - depends on DM_RESET && WDT_ASPEED
> + depends on DM_RESET
> default y if ASPEED_AST2500
> help
> - Support for reset controller on AST2500 SoC. This controller uses
> - watchdog to reset different peripherals and thus only supports
> - resets that are supported by watchdog. The main limitation though
> - is that some reset signals, like I2C or MISC reset multiple devices.
> + Support for reset controller on AST2500 SoC.
> + Say Y if you want to control reset signals of different peripherals
> + through System Control Unit (SCU).
>
> config RESET_ROCKCHIP
> bool "Reset controller driver for Rockchip SoCs"
> diff --git a/drivers/reset/ast2500-reset.c b/drivers/reset/ast2500-reset.c
> index
> beb5cd8fa8..e7b5c7deca 100644
> --- a/drivers/reset/ast2500-reset.c
> +++ b/drivers/reset/ast2500-reset.c
> @@ -1,6 +1,7 @@
> // SPDX-License-Identifier: GPL-2.0
> /*
> * Copyright 2017 Google, Inc
> + * Copyright 2020 ASPEED Technology Inc.
> */
>
> #include <common.h>
> @@ -9,28 +10,26 @@
> #include <misc.h>
> #include <reset.h>
> #include <reset-uclass.h>
> -#include <wdt.h>
> +#include <linux/err.h>
> #include <asm/io.h>
> #include <asm/arch/scu_ast2500.h>
> -#include <asm/arch/wdt.h>
>
> struct ast2500_reset_priv {
> - /* WDT used to perform resets. */
> - struct udevice *wdt;
> struct ast2500_scu *scu;
> };
>
> -static int ast2500_ofdata_to_platdata(struct udevice *dev)
> +static int ast2500_reset_request(struct reset_ctl *reset_ctl)
> {
> - struct ast2500_reset_priv *priv = dev_get_priv(dev);
> - int ret;
> + debug("%s(reset_ctl=%p) (dev=%p, id=%lu)\n", __func__, reset_ctl,
> + reset_ctl->dev, reset_ctl->id);
>
> - ret = uclass_get_device_by_phandle(UCLASS_WDT, dev, "aspeed,wdt",
> - &priv->wdt);
> - if (ret) {
> - debug("%s: can't find WDT for reset controller", __func__);
> - return ret;
> - }
> + return 0;
> +}
> +
> +static int ast2500_reset_free(struct reset_ctl *reset_ctl) {
> + debug("%s(reset_ctl=%p) (dev=%p, id=%lu)\n", __func__, reset_ctl,
> + reset_ctl->dev, reset_ctl->id);
>
> return 0;
> }
> @@ -38,47 +37,52 @@ static int ast2500_ofdata_to_platdata(struct udevice
> *dev) static int ast2500_reset_assert(struct reset_ctl *reset_ctl) {
> struct ast2500_reset_priv *priv = dev_get_priv(reset_ctl->dev);
> - u32 reset_mode, reset_mask;
> - bool reset_sdram;
> - int ret;
> -
> - /*
> - * To reset SDRAM, a specifal flag in SYSRESET register
> - * needs to be enabled first
> - */
> - reset_mode = ast_reset_mode_from_flags(reset_ctl->id);
> - reset_mask = ast_reset_mask_from_flags(reset_ctl->id);
> - reset_sdram = reset_mode == WDT_CTRL_RESET_SOC &&
> - (reset_mask & WDT_RESET_SDRAM);
> -
> - if (reset_sdram) {
> - ast_scu_unlock(priv->scu);
> - setbits_le32(&priv->scu->sysreset_ctrl1,
> - SCU_SYSRESET_SDRAM_WDT);
> - ret = wdt_expire_now(priv->wdt, reset_ctl->id);
> - clrbits_le32(&priv->scu->sysreset_ctrl1,
> - SCU_SYSRESET_SDRAM_WDT);
> - ast_scu_lock(priv->scu);
> - } else {
> - ret = wdt_expire_now(priv->wdt, reset_ctl->id);
> - }
> + struct ast2500_scu *scu = priv->scu;
> +
> + debug("%s: reset_ctl->id: %lu\n", __func__, reset_ctl->id);
>
> - return ret;
> + if (reset_ctl->id < 32)
> + setbits_le32(&scu->sysreset_ctrl1, BIT(reset_ctl->id));
> + else
> + setbits_le32(&scu->sysreset_ctrl2, BIT(reset_ctl->id - 32));
> +
> + return 0;
> }
>
> -static int ast2500_reset_request(struct reset_ctl *reset_ctl)
> +static int ast2500_reset_deassert(struct reset_ctl *reset_ctl)
> {
> - debug("%s(reset_ctl=%p) (dev=%p, id=%lu)\n", __func__, reset_ctl,
> - reset_ctl->dev, reset_ctl->id);
> + struct ast2500_reset_priv *priv = dev_get_priv(reset_ctl->dev);
> + struct ast2500_scu *scu = priv->scu;
> +
> + debug("%s: reset_ctl->id: %lu\n", __func__, reset_ctl->id);
> +
> + if (reset_ctl->id < 32)
> + clrbits_le32(&scu->sysreset_ctrl1, BIT(reset_ctl->id));
> + else
> + clrbits_le32(&scu->sysreset_ctrl2, BIT(reset_ctl->id - 32));
>
> return 0;
> }
>
> static int ast2500_reset_probe(struct udevice *dev) {
> + int rc;
> struct ast2500_reset_priv *priv = dev_get_priv(dev);
> + struct udevice *scu_dev;
> +
> + /* get SCU base from clock device */
> + rc = uclass_get_device_by_driver(UCLASS_CLK,
> + DM_GET_DRIVER(aspeed_ast2500_scu),
> &scu_dev);
> + if (rc) {
> + debug("%s: clock device not found, rc=%d\n", __func__, rc);
> + return rc;
> + }
>
> - priv->scu = ast_get_scu();
> + priv->scu = devfdt_get_addr_ptr(scu_dev);
> + if (IS_ERR_OR_NULL(priv->scu)) {
> + debug("%s: invalid SCU base pointer\n", __func__);
> + return PTR_ERR(priv->scu);
> + }
>
> return 0;
> }
> @@ -89,16 +93,17 @@ static const struct udevice_id ast2500_reset_ids[] =
> { };
>
> struct reset_ops ast2500_reset_ops = {
> - .rst_assert = ast2500_reset_assert,
> .request = ast2500_reset_request,
> + .rfree = ast2500_reset_free,
> + .rst_assert = ast2500_reset_assert,
> + .rst_deassert = ast2500_reset_deassert,
> };
>
> U_BOOT_DRIVER(ast2500_reset) = {
> - .name = "ast2500_reset",
> - .id = UCLASS_RESET,
> + .name = "ast2500_reset",
> + .id = UCLASS_RESET,
> .of_match = ast2500_reset_ids,
> .probe = ast2500_reset_probe,
> .ops = &ast2500_reset_ops,
> - .ofdata_to_platdata = ast2500_ofdata_to_platdata,
> .priv_auto_alloc_size = sizeof(struct ast2500_reset_priv), }; diff
> --git
> a/include/dt-bindings/reset/ast2500-reset.h
> b/include/dt-bindings/reset/ast2500-reset.h
> index d1b6b23fc1..cc85a31edf 100644
> --- a/include/dt-bindings/reset/ast2500-reset.h
> +++ b/include/dt-bindings/reset/ast2500-reset.h
> @@ -1,44 +1,49 @@
> /* SPDX-License-Identifier: GPL-2.0+ */
> /*
> * Copyright 2017 Google, Inc
> + * Copyright 2020 ASPEED Technology Inc.
> */
>
> #ifndef _ABI_MACH_ASPEED_AST2500_RESET_H_ #define
> _ABI_MACH_ASPEED_AST2500_RESET_H_
>
> -/*
> - * The values are intentionally layed out as flags in
> - * WDT reset parameter.
> - */
> -
> -#define AST_RESET_SOC 0
> -#define AST_RESET_CHIP 1
> -#define AST_RESET_CPU (1 << 1)
> -#define AST_RESET_ARM (1 << 2)
> -#define AST_RESET_COPROC (1 << 3)
> -#define AST_RESET_SDRAM (1 << 4)
> -#define AST_RESET_AHB (1 << 5)
> -#define AST_RESET_I2C (1 << 6)
> -#define AST_RESET_MAC1 (1 << 7)
> -#define AST_RESET_MAC2 (1 << 8)
> -#define AST_RESET_GCRT (1 << 9)
> -#define AST_RESET_USB20 (1 << 10)
> -#define AST_RESET_USB11_HOST (1 << 11)
> -#define AST_RESET_USB11_HID (1 << 12)
> -#define AST_RESET_VIDEO (1 << 13)
> -#define AST_RESET_HAC (1 << 14)
> -#define AST_RESET_LPC (1 << 15)
> -#define AST_RESET_SDIO (1 << 16)
> -#define AST_RESET_MIC (1 << 17)
> -#define AST_RESET_CRT2D (1 << 18)
> -#define AST_RESET_PWM (1 << 19)
> -#define AST_RESET_PECI (1 << 20)
> -#define AST_RESET_JTAG (1 << 21)
> -#define AST_RESET_ADC (1 << 22)
> -#define AST_RESET_GPIO (1 << 23)
> -#define AST_RESET_MCTP (1 << 24)
> -#define AST_RESET_XDMA (1 << 25)
> -#define AST_RESET_SPI (1 << 26)
> -#define AST_RESET_MISC (1 << 27)
> +#define ASPEED_RESET_CRT1 (37)
> +#define ASPEED_RESET_RESERVED36 (36)
> +#define ASPEED_RESET_RESERVED35 (35)
> +#define ASPEED_RESET_RESERVED34 (34)
> +#define ASPEED_RESET_RESERVED33 (33)
> +#define ASPEED_RESET_RESERVED32 (32)
> +#define ASPEED_RESET_RESERVED31 (31)
> +#define ASPEED_RESET_RESERVED30 (30)
> +#define ASPEED_RESET_RESERVED29 (29)
> +#define ASPEED_RESET_RESERVED28 (28)
> +#define ASPEED_RESET_RESERVED27 (27)
> +#define ASPEED_RESET_RESERVED26 (26)
> +#define ASPEED_RESET_XDMA (25)
> +#define ASPEED_RESET_MCTP (24)
> +#define ASPEED_RESET_ADC (23)
> +#define ASPEED_RESET_JTAG_MASTER (22)
> +#define ASPEED_RESET_RESERVED21 (21)
> +#define ASPEED_RESET_RESERVED20 (20)
> +#define ASPEED_RESET_RESERVED19 (19)
> +#define ASPEED_RESET_MIC (18)
> +#define ASPEED_RESET_RESERVED17 (17)
> +#define ASPEED_RESET_SDIO (16)
> +#define ASPEED_RESET_UHCI (15)
> +#define ASPEED_RESET_EHCI_P1 (14)
> +#define ASPEED_RESET_CRT (13)
> +#define ASPEED_RESET_MAC2 (12)
> +#define ASPEED_RESET_MAC1 (11)
> +#define ASPEED_RESET_PECI (10)
> +#define ASPEED_RESET_PWM (9)
> +#define ASPEED_RESET_PCI_VGA (8)
> +#define ASPEED_RESET_2D (7)
> +#define ASPEED_RESET_VIDEO (6)
> +#define ASPEED_RESET_LPC_ESPI (5)
> +#define ASPEED_RESET_HACE (4)
> +#define ASPEED_RESET_EHCI_P2 (3)
> +#define ASPEED_RESET_I2C (2)
> +#define ASPEED_RESET_AHB (1)
> +#define ASPEED_RESET_SDRAM (0)
>
> #endif /* _ABI_MACH_ASPEED_AST2500_RESET_H_ */
> --
> 2.17.1
