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peci: Add peci-aspeed controller driver
ASPEED AST24xx/AST25xx/AST26xx SoCs support the PECI electrical interface (a.k.a PECI wire) that provides a communication channel with Intel processors. This driver allows BMC to discover devices connected to it and communicate with them using PECI protocol. Co-developed-by: Iwona Winiarska <iwona.winiarska@intel.com> Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> Reviewed-by: Joel Stanley <joel@jms.id.au> Acked-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com> Signed-off-by: Iwona Winiarska <iwona.winiarska@intel.com> Link: https://lore.kernel.org/r/20220208153639.255278-6-iwona.winiarska@intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
parent
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@ -2986,6 +2986,14 @@ S: Maintained
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F: Documentation/devicetree/bindings/net/asix,ax88796c.yaml
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F: drivers/net/ethernet/asix/ax88796c_*
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ASPEED PECI CONTROLLER
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M: Iwona Winiarska <iwona.winiarska@intel.com>
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L: linux-aspeed@lists.ozlabs.org (moderated for non-subscribers)
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L: openbmc@lists.ozlabs.org (moderated for non-subscribers)
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S: Supported
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F: Documentation/devicetree/bindings/peci/peci-aspeed.yaml
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F: drivers/peci/controller/peci-aspeed.c
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ASPEED PINCTRL DRIVERS
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M: Andrew Jeffery <andrew@aj.id.au>
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L: linux-aspeed@lists.ozlabs.org (moderated for non-subscribers)
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@ -13,3 +13,9 @@ menuconfig PECI
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This support is also available as a module. If so, the module
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will be called peci.
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if PECI
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source "drivers/peci/controller/Kconfig"
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endif # PECI
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@ -3,3 +3,6 @@
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# Core functionality
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peci-y := core.o
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obj-$(CONFIG_PECI) += peci.o
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# Hardware specific bus drivers
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obj-y += controller/
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18
drivers/peci/controller/Kconfig
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18
drivers/peci/controller/Kconfig
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@ -0,0 +1,18 @@
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# SPDX-License-Identifier: GPL-2.0-only
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config PECI_ASPEED
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tristate "ASPEED PECI support"
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depends on ARCH_ASPEED || COMPILE_TEST
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depends on OF
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depends on HAS_IOMEM
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depends on COMMON_CLK
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help
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This option enables PECI controller driver for ASPEED AST2400,
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AST2500 and AST2600 SoCs. It allows BMC to discover devices
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connected to it, and communicate with them using PECI protocol.
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Say Y here if your system runs on ASPEED SoC and you are using it
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as BMC for Intel platform.
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This driver can also be built as a module. If so, the module will
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be called peci-aspeed.
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3
drivers/peci/controller/Makefile
Normal file
3
drivers/peci/controller/Makefile
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@ -0,0 +1,3 @@
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# SPDX-License-Identifier: GPL-2.0-only
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obj-$(CONFIG_PECI_ASPEED) += peci-aspeed.o
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599
drivers/peci/controller/peci-aspeed.c
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599
drivers/peci/controller/peci-aspeed.c
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@ -0,0 +1,599 @@
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// SPDX-License-Identifier: GPL-2.0-only
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// Copyright (c) 2012-2017 ASPEED Technology Inc.
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// Copyright (c) 2018-2021 Intel Corporation
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#include <asm/unaligned.h>
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#include <linux/bitfield.h>
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#include <linux/clk.h>
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#include <linux/clkdev.h>
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#include <linux/clk-provider.h>
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#include <linux/delay.h>
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#include <linux/interrupt.h>
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#include <linux/io.h>
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#include <linux/iopoll.h>
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#include <linux/jiffies.h>
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#include <linux/math.h>
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#include <linux/module.h>
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#include <linux/of.h>
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#include <linux/peci.h>
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#include <linux/platform_device.h>
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#include <linux/reset.h>
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/* ASPEED PECI Registers */
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/* Control Register */
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#define ASPEED_PECI_CTRL 0x00
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#define ASPEED_PECI_CTRL_SAMPLING_MASK GENMASK(19, 16)
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#define ASPEED_PECI_CTRL_RD_MODE_MASK GENMASK(13, 12)
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#define ASPEED_PECI_CTRL_RD_MODE_DBG BIT(13)
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#define ASPEED_PECI_CTRL_RD_MODE_COUNT BIT(12)
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#define ASPEED_PECI_CTRL_CLK_SRC_HCLK BIT(11)
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#define ASPEED_PECI_CTRL_CLK_DIV_MASK GENMASK(10, 8)
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#define ASPEED_PECI_CTRL_INVERT_OUT BIT(7)
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#define ASPEED_PECI_CTRL_INVERT_IN BIT(6)
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#define ASPEED_PECI_CTRL_BUS_CONTENTION_EN BIT(5)
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#define ASPEED_PECI_CTRL_PECI_EN BIT(4)
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#define ASPEED_PECI_CTRL_PECI_CLK_EN BIT(0)
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/* Timing Negotiation Register */
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#define ASPEED_PECI_TIMING_NEGOTIATION 0x04
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#define ASPEED_PECI_T_NEGO_MSG_MASK GENMASK(15, 8)
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#define ASPEED_PECI_T_NEGO_ADDR_MASK GENMASK(7, 0)
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/* Command Register */
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#define ASPEED_PECI_CMD 0x08
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#define ASPEED_PECI_CMD_PIN_MONITORING BIT(31)
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#define ASPEED_PECI_CMD_STS_MASK GENMASK(27, 24)
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#define ASPEED_PECI_CMD_STS_ADDR_T_NEGO 0x3
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#define ASPEED_PECI_CMD_IDLE_MASK \
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(ASPEED_PECI_CMD_STS_MASK | ASPEED_PECI_CMD_PIN_MONITORING)
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#define ASPEED_PECI_CMD_FIRE BIT(0)
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/* Read/Write Length Register */
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#define ASPEED_PECI_RW_LENGTH 0x0c
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#define ASPEED_PECI_AW_FCS_EN BIT(31)
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#define ASPEED_PECI_RD_LEN_MASK GENMASK(23, 16)
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#define ASPEED_PECI_WR_LEN_MASK GENMASK(15, 8)
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#define ASPEED_PECI_TARGET_ADDR_MASK GENMASK(7, 0)
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/* Expected FCS Data Register */
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#define ASPEED_PECI_EXPECTED_FCS 0x10
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#define ASPEED_PECI_EXPECTED_RD_FCS_MASK GENMASK(23, 16)
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#define ASPEED_PECI_EXPECTED_AW_FCS_AUTO_MASK GENMASK(15, 8)
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#define ASPEED_PECI_EXPECTED_WR_FCS_MASK GENMASK(7, 0)
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/* Captured FCS Data Register */
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#define ASPEED_PECI_CAPTURED_FCS 0x14
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#define ASPEED_PECI_CAPTURED_RD_FCS_MASK GENMASK(23, 16)
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#define ASPEED_PECI_CAPTURED_WR_FCS_MASK GENMASK(7, 0)
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/* Interrupt Register */
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#define ASPEED_PECI_INT_CTRL 0x18
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#define ASPEED_PECI_TIMING_NEGO_SEL_MASK GENMASK(31, 30)
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#define ASPEED_PECI_1ST_BIT_OF_ADDR_NEGO 0
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#define ASPEED_PECI_2ND_BIT_OF_ADDR_NEGO 1
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#define ASPEED_PECI_MESSAGE_NEGO 2
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#define ASPEED_PECI_INT_MASK GENMASK(4, 0)
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#define ASPEED_PECI_INT_BUS_TIMEOUT BIT(4)
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#define ASPEED_PECI_INT_BUS_CONTENTION BIT(3)
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#define ASPEED_PECI_INT_WR_FCS_BAD BIT(2)
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#define ASPEED_PECI_INT_WR_FCS_ABORT BIT(1)
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#define ASPEED_PECI_INT_CMD_DONE BIT(0)
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/* Interrupt Status Register */
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#define ASPEED_PECI_INT_STS 0x1c
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#define ASPEED_PECI_INT_TIMING_RESULT_MASK GENMASK(29, 16)
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/* bits[4..0]: Same bit fields in the 'Interrupt Register' */
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/* Rx/Tx Data Buffer Registers */
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#define ASPEED_PECI_WR_DATA0 0x20
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#define ASPEED_PECI_WR_DATA1 0x24
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#define ASPEED_PECI_WR_DATA2 0x28
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#define ASPEED_PECI_WR_DATA3 0x2c
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#define ASPEED_PECI_RD_DATA0 0x30
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#define ASPEED_PECI_RD_DATA1 0x34
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#define ASPEED_PECI_RD_DATA2 0x38
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#define ASPEED_PECI_RD_DATA3 0x3c
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#define ASPEED_PECI_WR_DATA4 0x40
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#define ASPEED_PECI_WR_DATA5 0x44
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#define ASPEED_PECI_WR_DATA6 0x48
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#define ASPEED_PECI_WR_DATA7 0x4c
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#define ASPEED_PECI_RD_DATA4 0x50
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#define ASPEED_PECI_RD_DATA5 0x54
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#define ASPEED_PECI_RD_DATA6 0x58
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#define ASPEED_PECI_RD_DATA7 0x5c
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#define ASPEED_PECI_DATA_BUF_SIZE_MAX 32
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/* Timing Negotiation */
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#define ASPEED_PECI_CLK_FREQUENCY_MIN 2000
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#define ASPEED_PECI_CLK_FREQUENCY_DEFAULT 1000000
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#define ASPEED_PECI_CLK_FREQUENCY_MAX 2000000
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#define ASPEED_PECI_RD_SAMPLING_POINT_DEFAULT 8
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/* Timeout */
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#define ASPEED_PECI_IDLE_CHECK_TIMEOUT_US (50 * USEC_PER_MSEC)
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#define ASPEED_PECI_IDLE_CHECK_INTERVAL_US (10 * USEC_PER_MSEC)
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#define ASPEED_PECI_CMD_TIMEOUT_MS_DEFAULT 1000
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#define ASPEED_PECI_CMD_TIMEOUT_MS_MAX 1000
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#define ASPEED_PECI_CLK_DIV1(msg_timing) (4 * (msg_timing) + 1)
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#define ASPEED_PECI_CLK_DIV2(clk_div_exp) BIT(clk_div_exp)
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#define ASPEED_PECI_CLK_DIV(msg_timing, clk_div_exp) \
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(4 * ASPEED_PECI_CLK_DIV1(msg_timing) * ASPEED_PECI_CLK_DIV2(clk_div_exp))
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struct aspeed_peci {
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struct peci_controller *controller;
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struct device *dev;
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void __iomem *base;
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struct reset_control *rst;
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int irq;
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spinlock_t lock; /* to sync completion status handling */
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struct completion xfer_complete;
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struct clk *clk;
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u32 clk_frequency;
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u32 status;
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u32 cmd_timeout_ms;
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};
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struct clk_aspeed_peci {
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struct clk_hw hw;
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struct aspeed_peci *aspeed_peci;
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};
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static void aspeed_peci_controller_enable(struct aspeed_peci *priv)
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{
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u32 val = readl(priv->base + ASPEED_PECI_CTRL);
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val |= ASPEED_PECI_CTRL_PECI_CLK_EN;
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val |= ASPEED_PECI_CTRL_PECI_EN;
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writel(val, priv->base + ASPEED_PECI_CTRL);
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}
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static void aspeed_peci_init_regs(struct aspeed_peci *priv)
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{
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u32 val;
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/* Clear interrupts */
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writel(ASPEED_PECI_INT_MASK, priv->base + ASPEED_PECI_INT_STS);
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/* Set timing negotiation mode and enable interrupts */
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val = FIELD_PREP(ASPEED_PECI_TIMING_NEGO_SEL_MASK, ASPEED_PECI_1ST_BIT_OF_ADDR_NEGO);
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val |= ASPEED_PECI_INT_MASK;
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writel(val, priv->base + ASPEED_PECI_INT_CTRL);
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val = FIELD_PREP(ASPEED_PECI_CTRL_SAMPLING_MASK, ASPEED_PECI_RD_SAMPLING_POINT_DEFAULT);
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writel(val, priv->base + ASPEED_PECI_CTRL);
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}
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static int aspeed_peci_check_idle(struct aspeed_peci *priv)
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{
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u32 cmd_sts = readl(priv->base + ASPEED_PECI_CMD);
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int ret;
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/*
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* Under normal circumstances, we expect to be idle here.
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* In case there were any errors/timeouts that led to the situation
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* where the hardware is not in idle state - we need to reset and
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* reinitialize it to avoid potential controller hang.
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*/
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if (FIELD_GET(ASPEED_PECI_CMD_STS_MASK, cmd_sts)) {
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ret = reset_control_assert(priv->rst);
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if (ret) {
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dev_err(priv->dev, "cannot assert reset control\n");
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return ret;
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}
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ret = reset_control_deassert(priv->rst);
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if (ret) {
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dev_err(priv->dev, "cannot deassert reset control\n");
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return ret;
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}
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aspeed_peci_init_regs(priv);
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ret = clk_set_rate(priv->clk, priv->clk_frequency);
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if (ret < 0) {
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dev_err(priv->dev, "cannot set clock frequency\n");
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return ret;
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}
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aspeed_peci_controller_enable(priv);
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}
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return readl_poll_timeout(priv->base + ASPEED_PECI_CMD,
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cmd_sts,
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!(cmd_sts & ASPEED_PECI_CMD_IDLE_MASK),
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ASPEED_PECI_IDLE_CHECK_INTERVAL_US,
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ASPEED_PECI_IDLE_CHECK_TIMEOUT_US);
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}
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static int aspeed_peci_xfer(struct peci_controller *controller,
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u8 addr, struct peci_request *req)
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{
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struct aspeed_peci *priv = dev_get_drvdata(controller->dev.parent);
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unsigned long timeout = msecs_to_jiffies(priv->cmd_timeout_ms);
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u32 peci_head;
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int ret, i;
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if (req->tx.len > ASPEED_PECI_DATA_BUF_SIZE_MAX ||
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req->rx.len > ASPEED_PECI_DATA_BUF_SIZE_MAX)
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return -EINVAL;
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/* Check command sts and bus idle state */
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ret = aspeed_peci_check_idle(priv);
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if (ret)
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return ret; /* -ETIMEDOUT */
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spin_lock_irq(&priv->lock);
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reinit_completion(&priv->xfer_complete);
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peci_head = FIELD_PREP(ASPEED_PECI_TARGET_ADDR_MASK, addr) |
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FIELD_PREP(ASPEED_PECI_WR_LEN_MASK, req->tx.len) |
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FIELD_PREP(ASPEED_PECI_RD_LEN_MASK, req->rx.len);
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writel(peci_head, priv->base + ASPEED_PECI_RW_LENGTH);
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for (i = 0; i < req->tx.len; i += 4) {
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u32 reg = (i < 16 ? ASPEED_PECI_WR_DATA0 : ASPEED_PECI_WR_DATA4) + i % 16;
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writel(get_unaligned_le32(&req->tx.buf[i]), priv->base + reg);
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}
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#if IS_ENABLED(CONFIG_DYNAMIC_DEBUG)
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dev_dbg(priv->dev, "HEAD : %#08x\n", peci_head);
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print_hex_dump_bytes("TX : ", DUMP_PREFIX_NONE, req->tx.buf, req->tx.len);
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#endif
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priv->status = 0;
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writel(ASPEED_PECI_CMD_FIRE, priv->base + ASPEED_PECI_CMD);
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spin_unlock_irq(&priv->lock);
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ret = wait_for_completion_interruptible_timeout(&priv->xfer_complete, timeout);
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if (ret < 0)
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return ret;
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if (ret == 0) {
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dev_dbg(priv->dev, "timeout waiting for a response\n");
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return -ETIMEDOUT;
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}
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spin_lock_irq(&priv->lock);
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if (priv->status != ASPEED_PECI_INT_CMD_DONE) {
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spin_unlock_irq(&priv->lock);
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dev_dbg(priv->dev, "no valid response, status: %#02x\n", priv->status);
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return -EIO;
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}
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spin_unlock_irq(&priv->lock);
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/*
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* We need to use dword reads for register access, make sure that the
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* buffer size is multiple of 4-bytes.
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*/
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BUILD_BUG_ON(PECI_REQUEST_MAX_BUF_SIZE % 4);
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for (i = 0; i < req->rx.len; i += 4) {
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u32 reg = (i < 16 ? ASPEED_PECI_RD_DATA0 : ASPEED_PECI_RD_DATA4) + i % 16;
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u32 rx_data = readl(priv->base + reg);
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put_unaligned_le32(rx_data, &req->rx.buf[i]);
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}
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#if IS_ENABLED(CONFIG_DYNAMIC_DEBUG)
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print_hex_dump_bytes("RX : ", DUMP_PREFIX_NONE, req->rx.buf, req->rx.len);
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#endif
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return 0;
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}
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static irqreturn_t aspeed_peci_irq_handler(int irq, void *arg)
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{
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struct aspeed_peci *priv = arg;
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u32 status;
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spin_lock(&priv->lock);
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status = readl(priv->base + ASPEED_PECI_INT_STS);
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writel(status, priv->base + ASPEED_PECI_INT_STS);
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priv->status |= (status & ASPEED_PECI_INT_MASK);
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/*
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* All commands should be ended up with a ASPEED_PECI_INT_CMD_DONE bit
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* set even in an error case.
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*/
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if (status & ASPEED_PECI_INT_CMD_DONE)
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complete(&priv->xfer_complete);
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writel(0, priv->base + ASPEED_PECI_CMD);
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spin_unlock(&priv->lock);
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return IRQ_HANDLED;
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}
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static void clk_aspeed_peci_find_div_values(unsigned long rate, int *msg_timing, int *clk_div_exp)
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{
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unsigned long best_diff = ~0ul, diff;
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int msg_timing_temp, clk_div_exp_temp, i, j;
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for (i = 1; i <= 255; i++)
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for (j = 0; j < 8; j++) {
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diff = abs(rate - ASPEED_PECI_CLK_DIV1(i) * ASPEED_PECI_CLK_DIV2(j));
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if (diff < best_diff) {
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msg_timing_temp = i;
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clk_div_exp_temp = j;
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best_diff = diff;
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}
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}
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|
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*msg_timing = msg_timing_temp;
|
||||
*clk_div_exp = clk_div_exp_temp;
|
||||
}
|
||||
|
||||
static int clk_aspeed_peci_get_div(unsigned long rate, const unsigned long *prate)
|
||||
{
|
||||
unsigned long this_rate = *prate / (4 * rate);
|
||||
int msg_timing, clk_div_exp;
|
||||
|
||||
clk_aspeed_peci_find_div_values(this_rate, &msg_timing, &clk_div_exp);
|
||||
|
||||
return ASPEED_PECI_CLK_DIV(msg_timing, clk_div_exp);
|
||||
}
|
||||
|
||||
static int clk_aspeed_peci_set_rate(struct clk_hw *hw, unsigned long rate,
|
||||
unsigned long prate)
|
||||
{
|
||||
struct clk_aspeed_peci *peci_clk = container_of(hw, struct clk_aspeed_peci, hw);
|
||||
struct aspeed_peci *aspeed_peci = peci_clk->aspeed_peci;
|
||||
unsigned long this_rate = prate / (4 * rate);
|
||||
int clk_div_exp, msg_timing;
|
||||
u32 val;
|
||||
|
||||
clk_aspeed_peci_find_div_values(this_rate, &msg_timing, &clk_div_exp);
|
||||
|
||||
val = readl(aspeed_peci->base + ASPEED_PECI_CTRL);
|
||||
val |= FIELD_PREP(ASPEED_PECI_CTRL_CLK_DIV_MASK, clk_div_exp);
|
||||
writel(val, aspeed_peci->base + ASPEED_PECI_CTRL);
|
||||
|
||||
val = FIELD_PREP(ASPEED_PECI_T_NEGO_MSG_MASK, msg_timing);
|
||||
val |= FIELD_PREP(ASPEED_PECI_T_NEGO_ADDR_MASK, msg_timing);
|
||||
writel(val, aspeed_peci->base + ASPEED_PECI_TIMING_NEGOTIATION);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static long clk_aspeed_peci_round_rate(struct clk_hw *hw, unsigned long rate,
|
||||
unsigned long *prate)
|
||||
{
|
||||
int div = clk_aspeed_peci_get_div(rate, prate);
|
||||
|
||||
return DIV_ROUND_UP_ULL(*prate, div);
|
||||
}
|
||||
|
||||
static unsigned long clk_aspeed_peci_recalc_rate(struct clk_hw *hw, unsigned long prate)
|
||||
{
|
||||
struct clk_aspeed_peci *peci_clk = container_of(hw, struct clk_aspeed_peci, hw);
|
||||
struct aspeed_peci *aspeed_peci = peci_clk->aspeed_peci;
|
||||
int div, msg_timing, addr_timing, clk_div_exp;
|
||||
u32 reg;
|
||||
|
||||
reg = readl(aspeed_peci->base + ASPEED_PECI_TIMING_NEGOTIATION);
|
||||
msg_timing = FIELD_GET(ASPEED_PECI_T_NEGO_MSG_MASK, reg);
|
||||
addr_timing = FIELD_GET(ASPEED_PECI_T_NEGO_ADDR_MASK, reg);
|
||||
|
||||
if (msg_timing != addr_timing)
|
||||
return 0;
|
||||
|
||||
reg = readl(aspeed_peci->base + ASPEED_PECI_CTRL);
|
||||
clk_div_exp = FIELD_GET(ASPEED_PECI_CTRL_CLK_DIV_MASK, reg);
|
||||
|
||||
div = ASPEED_PECI_CLK_DIV(msg_timing, clk_div_exp);
|
||||
|
||||
return DIV_ROUND_UP_ULL(prate, div);
|
||||
}
|
||||
|
||||
static const struct clk_ops clk_aspeed_peci_ops = {
|
||||
.set_rate = clk_aspeed_peci_set_rate,
|
||||
.round_rate = clk_aspeed_peci_round_rate,
|
||||
.recalc_rate = clk_aspeed_peci_recalc_rate,
|
||||
};
|
||||
|
||||
/*
|
||||
* PECI HW contains a clock divider which is a combination of:
|
||||
* div0: 4 (fixed divider)
|
||||
* div1: x + 1
|
||||
* div2: 1 << y
|
||||
* In other words, out_clk = in_clk / (div0 * div1 * div2)
|
||||
* The resulting frequency is used by PECI Controller to drive the PECI bus to
|
||||
* negotiate optimal transfer rate.
|
||||
*/
|
||||
static struct clk *devm_aspeed_peci_register_clk_div(struct device *dev, struct clk *parent,
|
||||
struct aspeed_peci *priv)
|
||||
{
|
||||
struct clk_aspeed_peci *peci_clk;
|
||||
struct clk_init_data init;
|
||||
const char *parent_name;
|
||||
char name[32];
|
||||
int ret;
|
||||
|
||||
snprintf(name, sizeof(name), "%s_div", dev_name(dev));
|
||||
|
||||
parent_name = __clk_get_name(parent);
|
||||
|
||||
init.ops = &clk_aspeed_peci_ops;
|
||||
init.name = name;
|
||||
init.parent_names = (const char* []) { parent_name };
|
||||
init.num_parents = 1;
|
||||
init.flags = 0;
|
||||
|
||||
peci_clk = devm_kzalloc(dev, sizeof(struct clk_aspeed_peci), GFP_KERNEL);
|
||||
if (!peci_clk)
|
||||
return ERR_PTR(-ENOMEM);
|
||||
|
||||
peci_clk->hw.init = &init;
|
||||
peci_clk->aspeed_peci = priv;
|
||||
|
||||
ret = devm_clk_hw_register(dev, &peci_clk->hw);
|
||||
if (ret)
|
||||
return ERR_PTR(ret);
|
||||
|
||||
return peci_clk->hw.clk;
|
||||
}
|
||||
|
||||
static void aspeed_peci_property_sanitize(struct device *dev, const char *propname,
|
||||
u32 min, u32 max, u32 default_val, u32 *propval)
|
||||
{
|
||||
u32 val;
|
||||
int ret;
|
||||
|
||||
ret = device_property_read_u32(dev, propname, &val);
|
||||
if (ret) {
|
||||
val = default_val;
|
||||
} else if (val > max || val < min) {
|
||||
dev_warn(dev, "invalid %s: %u, falling back to: %u\n",
|
||||
propname, val, default_val);
|
||||
|
||||
val = default_val;
|
||||
}
|
||||
|
||||
*propval = val;
|
||||
}
|
||||
|
||||
static void aspeed_peci_property_setup(struct aspeed_peci *priv)
|
||||
{
|
||||
aspeed_peci_property_sanitize(priv->dev, "clock-frequency",
|
||||
ASPEED_PECI_CLK_FREQUENCY_MIN, ASPEED_PECI_CLK_FREQUENCY_MAX,
|
||||
ASPEED_PECI_CLK_FREQUENCY_DEFAULT, &priv->clk_frequency);
|
||||
aspeed_peci_property_sanitize(priv->dev, "cmd-timeout-ms",
|
||||
1, ASPEED_PECI_CMD_TIMEOUT_MS_MAX,
|
||||
ASPEED_PECI_CMD_TIMEOUT_MS_DEFAULT, &priv->cmd_timeout_ms);
|
||||
}
|
||||
|
||||
static struct peci_controller_ops aspeed_ops = {
|
||||
.xfer = aspeed_peci_xfer,
|
||||
};
|
||||
|
||||
static void aspeed_peci_reset_control_release(void *data)
|
||||
{
|
||||
reset_control_assert(data);
|
||||
}
|
||||
|
||||
static int devm_aspeed_peci_reset_control_deassert(struct device *dev, struct reset_control *rst)
|
||||
{
|
||||
int ret;
|
||||
|
||||
ret = reset_control_deassert(rst);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
return devm_add_action_or_reset(dev, aspeed_peci_reset_control_release, rst);
|
||||
}
|
||||
|
||||
static void aspeed_peci_clk_release(void *data)
|
||||
{
|
||||
clk_disable_unprepare(data);
|
||||
}
|
||||
|
||||
static int devm_aspeed_peci_clk_enable(struct device *dev, struct clk *clk)
|
||||
{
|
||||
int ret;
|
||||
|
||||
ret = clk_prepare_enable(clk);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
return devm_add_action_or_reset(dev, aspeed_peci_clk_release, clk);
|
||||
}
|
||||
|
||||
static int aspeed_peci_probe(struct platform_device *pdev)
|
||||
{
|
||||
struct peci_controller *controller;
|
||||
struct aspeed_peci *priv;
|
||||
struct clk *ref_clk;
|
||||
int ret;
|
||||
|
||||
priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
|
||||
if (!priv)
|
||||
return -ENOMEM;
|
||||
|
||||
priv->dev = &pdev->dev;
|
||||
dev_set_drvdata(priv->dev, priv);
|
||||
|
||||
priv->base = devm_platform_ioremap_resource(pdev, 0);
|
||||
if (IS_ERR(priv->base))
|
||||
return PTR_ERR(priv->base);
|
||||
|
||||
priv->irq = platform_get_irq(pdev, 0);
|
||||
if (!priv->irq)
|
||||
return priv->irq;
|
||||
|
||||
ret = devm_request_irq(&pdev->dev, priv->irq, aspeed_peci_irq_handler,
|
||||
0, "peci-aspeed", priv);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
init_completion(&priv->xfer_complete);
|
||||
spin_lock_init(&priv->lock);
|
||||
|
||||
priv->rst = devm_reset_control_get(&pdev->dev, NULL);
|
||||
if (IS_ERR(priv->rst))
|
||||
return dev_err_probe(priv->dev, PTR_ERR(priv->rst),
|
||||
"failed to get reset control\n");
|
||||
|
||||
ret = devm_aspeed_peci_reset_control_deassert(priv->dev, priv->rst);
|
||||
if (ret)
|
||||
return dev_err_probe(priv->dev, ret, "cannot deassert reset control\n");
|
||||
|
||||
aspeed_peci_property_setup(priv);
|
||||
|
||||
aspeed_peci_init_regs(priv);
|
||||
|
||||
ref_clk = devm_clk_get(priv->dev, NULL);
|
||||
if (IS_ERR(ref_clk))
|
||||
return dev_err_probe(priv->dev, PTR_ERR(ref_clk), "failed to get ref clock\n");
|
||||
|
||||
priv->clk = devm_aspeed_peci_register_clk_div(priv->dev, ref_clk, priv);
|
||||
if (IS_ERR(priv->clk))
|
||||
return dev_err_probe(priv->dev, PTR_ERR(priv->clk), "cannot register clock\n");
|
||||
|
||||
ret = clk_set_rate(priv->clk, priv->clk_frequency);
|
||||
if (ret < 0)
|
||||
return dev_err_probe(priv->dev, ret, "cannot set clock frequency\n");
|
||||
|
||||
ret = devm_aspeed_peci_clk_enable(priv->dev, priv->clk);
|
||||
if (ret)
|
||||
return dev_err_probe(priv->dev, ret, "failed to enable clock\n");
|
||||
|
||||
aspeed_peci_controller_enable(priv);
|
||||
|
||||
controller = devm_peci_controller_add(priv->dev, &aspeed_ops);
|
||||
if (IS_ERR(controller))
|
||||
return dev_err_probe(priv->dev, PTR_ERR(controller),
|
||||
"failed to add aspeed peci controller\n");
|
||||
|
||||
priv->controller = controller;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static const struct of_device_id aspeed_peci_of_table[] = {
|
||||
{ .compatible = "aspeed,ast2400-peci", },
|
||||
{ .compatible = "aspeed,ast2500-peci", },
|
||||
{ .compatible = "aspeed,ast2600-peci", },
|
||||
{ }
|
||||
};
|
||||
MODULE_DEVICE_TABLE(of, aspeed_peci_of_table);
|
||||
|
||||
static struct platform_driver aspeed_peci_driver = {
|
||||
.probe = aspeed_peci_probe,
|
||||
.driver = {
|
||||
.name = "peci-aspeed",
|
||||
.of_match_table = aspeed_peci_of_table,
|
||||
},
|
||||
};
|
||||
module_platform_driver(aspeed_peci_driver);
|
||||
|
||||
MODULE_AUTHOR("Ryan Chen <ryan_chen@aspeedtech.com>");
|
||||
MODULE_AUTHOR("Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com>");
|
||||
MODULE_DESCRIPTION("ASPEED PECI driver");
|
||||
MODULE_LICENSE("GPL");
|
||||
MODULE_IMPORT_NS(PECI);
|
Loading…
Reference in New Issue
Block a user