From c3bfbafda5c3241ff74ec1de3fbdc469af0e4ce0 Mon Sep 17 00:00:00 2001 From: Abel Briggs Date: Thu, 14 Apr 2022 22:08:41 -0500 Subject: ec/acpi: Rework to reduce code duplication - Move EC send/receive polling code to their own functions - Add named constants for poll timeouts and delay interval - Use human-readable timeout values - Add `send`/`recv` functions which support custom timeouts - Remove extra 10us delays between polling and performing a given transaction - Use constants from `ec.h` for standard EC command opcodes Tested on a Lenovo Edge E530, which takes similar code paths to the Lenovo Twist S230u. Change-Id: Ifda5c030ff81f1046be58aa1fcafdcf71a27cd41 Signed-off-by: Abel Briggs Reviewed-on: https://review.coreboot.org/c/coreboot/+/64012 Tested-by: build bot (Jenkins) Reviewed-by: Lean Sheng Tan --- src/ec/acpi/ec.c | 101 +++++++++++++++++++++++++++++-------------------------- src/ec/acpi/ec.h | 10 ++++-- 2 files changed, 60 insertions(+), 51 deletions(-) (limited to 'src/ec') diff --git a/src/ec/acpi/ec.c b/src/ec/acpi/ec.c index 76ec8fe2bd..7d495a1264 100644 --- a/src/ec/acpi/ec.c +++ b/src/ec/acpi/ec.c @@ -1,88 +1,92 @@ /* SPDX-License-Identifier: GPL-2.0-only */ #include -#include #include #include -#include +#include #include "ec.h" +#define EC_POLL_DELAY_US 10 +#define EC_SEND_TIMEOUT_US 20000 // 20ms +#define EC_RECV_TIMEOUT_US 320000 // 320ms + static u16 ec_cmd_reg = EC_SC; static u16 ec_data_reg = EC_DATA; +/* + * Poll the EC status/command register for a specified + * state until the given timeout elapses. + */ +static int wait_ec_sc(int timeout_us, u8 mask, u8 state) +{ + while (timeout_us > 0 && (inb(ec_cmd_reg) & mask) != state) { + udelay(EC_POLL_DELAY_US); + timeout_us -= EC_POLL_DELAY_US; + } + + return timeout_us > 0 ? 0 : -1; +} + +bool ec_ready_send(int timeout_us) +{ + return wait_ec_sc(timeout_us, EC_IBF, 0) == 0; +} + +bool ec_ready_recv(int timeout_us) +{ + return wait_ec_sc(timeout_us, EC_OBF, EC_OBF) == 0; +} + int send_ec_command(u8 command) { - int timeout; + return send_ec_command_timeout(command, EC_SEND_TIMEOUT_US); +} - timeout = 0x7ff; - while ((inb(ec_cmd_reg) & EC_IBF) && --timeout) { - udelay(10); - if ((timeout & 0xff) == 0) - printk(BIOS_SPEW, "."); - } - if (!timeout) { +int send_ec_command_timeout(u8 command, int timeout_us) +{ + if (!ec_ready_send(timeout_us)) { printk(BIOS_DEBUG, "Timeout while sending command 0x%02x to EC!\n", command); // return -1; } - udelay(10); - outb(command, ec_cmd_reg); + return 0; } int send_ec_data(u8 data) { - int timeout; + return send_ec_data_timeout(data, EC_SEND_TIMEOUT_US); +} - timeout = 0x7ff; - while ((inb(ec_cmd_reg) & EC_IBF) && --timeout) { // wait for IBF = 0 - udelay(10); - if ((timeout & 0xff) == 0) - printk(BIOS_SPEW, "."); - } - if (!timeout) { +int send_ec_data_timeout(u8 data, int timeout_us) +{ + if (!ec_ready_send(timeout_us)) { printk(BIOS_DEBUG, "Timeout while sending data 0x%02x to EC!\n", data); // return -1; } - udelay(10); - outb(data, ec_data_reg); return 0; } -int send_ec_data_nowait(u8 data) +u8 recv_ec_data(void) { - outb(data, ec_data_reg); - - return 0; + return recv_ec_data_timeout(EC_RECV_TIMEOUT_US); } -u8 recv_ec_data(void) +u8 recv_ec_data_timeout(int timeout_us) { - int timeout; u8 data; - timeout = 0x7fff; - while (--timeout) { // Wait for OBF = 1 - if (inb(ec_cmd_reg) & EC_OBF) { - break; - } - udelay(10); - if ((timeout & 0xff) == 0) - printk(BIOS_SPEW, "."); - } - if (!timeout) { - printk(BIOS_DEBUG, "\nTimeout while receiving data from EC!\n"); + if (!ec_ready_recv(timeout_us)) { + printk(BIOS_DEBUG, "Timeout while receiving data from EC!\n"); // return -1; } - udelay(10); - data = inb(ec_data_reg); printk(BIOS_SPEW, "%s: 0x%02x\n", __func__, data); @@ -91,14 +95,15 @@ u8 recv_ec_data(void) void ec_clear_out_queue(void) { - int timeout = 0x7fff; + int timeout = EC_RECV_TIMEOUT_US; printk(BIOS_SPEW, "Clearing EC output queue...\n"); - while (--timeout && (inb(ec_cmd_reg) & EC_OBF)) { + while (timeout > 0 && inb(ec_cmd_reg) & EC_OBF) { u8 data = inb(ec_data_reg); printk(BIOS_SPEW, "Discarding a garbage byte: 0x%02x\n", data); - udelay(10); + udelay(EC_POLL_DELAY_US); + timeout -= EC_POLL_DELAY_US; } - if (!timeout) + if (timeout <= 0) printk(BIOS_ERR, "Timeout while clearing EC output queue!\n"); else printk(BIOS_SPEW, "EC output queue has been cleared.\n"); @@ -106,7 +111,7 @@ void ec_clear_out_queue(void) u8 ec_read(u8 addr) { - send_ec_command(0x80); + send_ec_command(RD_EC); send_ec_data(addr); return recv_ec_data(); @@ -114,7 +119,7 @@ u8 ec_read(u8 addr) int ec_write(u8 addr, u8 data) { - send_ec_command(0x81); + send_ec_command(WR_EC); send_ec_data(addr); return send_ec_data(data); } @@ -126,7 +131,7 @@ u8 ec_status(void) u8 ec_query(void) { - send_ec_command(0x84); + send_ec_command(QR_EC); return recv_ec_data(); } diff --git a/src/ec/acpi/ec.h b/src/ec/acpi/ec.h index f176d7be03..665c62f559 100644 --- a/src/ec/acpi/ec.h +++ b/src/ec/acpi/ec.h @@ -3,7 +3,7 @@ #ifndef _EC_ACPI_H #define _EC_ACPI_H -#include +#include #define EC_DATA 0x62 #define EC_SC 0x66 @@ -11,7 +11,7 @@ /* EC_SC input */ #define EC_SMI_EVT (1 << 6) // 1: SMI event pending #define EC_SCI_EVT (1 << 5) // 1: SCI event pending -#define EC_BURST (1 << 4) // controller is in burst mode +#define EC_BURST (1 << 4) // 1: controller is in burst mode #define EC_CMD (1 << 3) // 1: byte in data register is command // 0: byte in data register is data #define EC_IBF (1 << 1) // 1: input buffer full (data ready for ec) @@ -23,10 +23,14 @@ #define BD_EC 0x83 // Burst Disable Embedded Controller #define QR_EC 0x84 // Query Embedded Controller +bool ec_ready_send(int timeout_us); +bool ec_ready_recv(int timeout_us); int send_ec_command(u8 command); +int send_ec_command_timeout(u8 command, int timeout); int send_ec_data(u8 data); -int send_ec_data_nowait(u8 data); +int send_ec_data_timeout(u8 data, int timeout); u8 recv_ec_data(void); +u8 recv_ec_data_timeout(int timeout); void ec_clear_out_queue(void); u8 ec_status(void); u8 ec_query(void); -- cgit v1.2.3