From 4c961e20744579a2ba8c4de7ad1e7ecb22702f09 Mon Sep 17 00:00:00 2001 From: Ian Moffett Date: Mon, 17 Nov 2025 15:21:32 -0500 Subject: kern: dev: Add HPET timer driver Signed-off-by: Ian Moffett --- sys/acpi/acpi.c | 9 +++ sys/dev/clkdev/hpet.c | 150 ++++++++++++++++++++++++++++++++++++++++++++++ sys/inc/dev/clkdev/hpet.h | 45 ++++++++++++++ 3 files changed, 204 insertions(+) create mode 100644 sys/dev/clkdev/hpet.c create mode 100644 sys/inc/dev/clkdev/hpet.h diff --git a/sys/acpi/acpi.c b/sys/acpi/acpi.c index a521e12..f60435b 100644 --- a/sys/acpi/acpi.c +++ b/sys/acpi/acpi.c @@ -33,6 +33,7 @@ #include #include #include +#include #include #include #include @@ -113,6 +114,8 @@ acpi_query(const char *s) void acpi_init(void) { + int error; + rsdp_resp = rsdp_req.response; if (__unlikely(rsdp_resp == NULL)) { panic("acpi: could not obtain rsdp\n"); @@ -138,4 +141,10 @@ acpi_init(void) } dtrace("OK\n"); + error = hpet_init(); +#if defined(__x86_64__) + if (error != 0) { + panic("acpi: require HPET on RV7/x86_64\n"); + } +#endif /* __x86_64__ */ } diff --git a/sys/dev/clkdev/hpet.c b/sys/dev/clkdev/hpet.c new file mode 100644 index 0000000..8171260 --- /dev/null +++ b/sys/dev/clkdev/hpet.c @@ -0,0 +1,150 @@ +/* + * Copyright (c) 2023-2025 Ian Marco Moffett and the Osmora Team. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * 1. Redistributions of source code must retain the above copyright notice, + * this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of Hyra nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE + * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define dtrace(fmt, ...) trace("hpet: " fmt, ##__VA_ARGS__) + +/* HPET register offsets */ +#define HPET_GCAP_ID 0x00 /* Global capabilities and ID */ +#define HPET_GCONF 0x10 /* General configuration register */ +#define HPET_COUNTER0 0xF0 /* Main counter register */ + +#define CAP_REV_ID(caps) (caps & 0xFF) +#define CAP_NUM_TIM(caps) (caps >> 8) & 0x1F +#define CAP_CLK_PERIOD(caps) (caps >> 32) + +static volatile uint64_t *hpet_base; +static bool hpet_enabled = false; + +/* + * Read a 64-bit unsigned value from an HPET + * register + */ +static inline uint64_t +hpet_readq(uint16_t reg) +{ + uint64_t *base; + + base = PTR_OFFSET(hpet_base, reg); + return mmio_read64(base); +} + +/* + * Write a 64-bit unsigned value to an HPET + * register + */ +static inline void +hpet_writeq(uint16_t reg, uint64_t val) +{ + uint64_t *base; + + base = PTR_OFFSET(hpet_base, reg); + mmio_write32(base, val); +} + +static void +hpet_sleep(uint64_t n, uint64_t units) +{ + uint64_t period, caps; + uint64_t counter; + uint64_t ticks; + + if (!hpet_enabled) { + return; + } + + caps = hpet_readq(HPET_GCAP_ID); + period = CAP_CLK_PERIOD(caps); + counter = hpet_readq(HPET_COUNTER0); + ticks = counter + (n * (units / period)); + + while (hpet_readq(HPET_COUNTER0) < ticks); +} + +void +hpet_msleep(size_t ms) +{ + hpet_sleep(ms, 1000000000000); +} + +int +hpet_init(void) +{ + struct acpi_hpet *hpet; + struct acpi_gas *gas; + uint64_t gcap, gconf, counter; + uint32_t clk_period; + uint8_t rev_id; + uint8_t num_timer; + + hpet = acpi_query("HPET"); + if (hpet == NULL) { + return -ENODEV; + } + + gas = &hpet->gas; + hpet_base = PHYS_TO_VIRT(gas->address); + gcap = hpet_readq(HPET_GCAP_ID); + + /* Verify its values */ + clk_period = CAP_CLK_PERIOD(gcap); + num_timer = CAP_NUM_TIM(gcap); + rev_id = gcap & 0xFF; + if (rev_id == 0) { + dtrace("bad hpet revision, cannot be zero\n"); + panic("hpet: system self test failure\n"); + } + + /* Verify the clock period */ + if (clk_period == 0 || clk_period > 0x05F5E100) { + dtrace("bad hpet clock period\n"); + panic("hpet: system self test failure\n"); + } + + dtrace("rev=%d, num_timer=%d\n", rev_id, num_timer); + dtrace("clk_period=%d\n", clk_period); + + hpet_writeq(HPET_COUNTER0, 0); /* Clear the counter */ + hpet_writeq(HPET_GCONF, 1); /* Enable timer */ + + hpet_enabled = true; + dtrace("OK\n"); + return 0; +} diff --git a/sys/inc/dev/clkdev/hpet.h b/sys/inc/dev/clkdev/hpet.h new file mode 100644 index 0000000..6519f5f --- /dev/null +++ b/sys/inc/dev/clkdev/hpet.h @@ -0,0 +1,45 @@ +/* + * Copyright (c) 2023-2025 Ian Marco Moffett and the Osmora Team. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * 1. Redistributions of source code must retain the above copyright notice, + * this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of Hyra nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE + * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + */ + +#ifndef _CLKDEV_HPET_H_ +#define _CLKDEV_HPET_H_ 1 + +#include + +/* + * Sleep for a number of miliseconds + */ +void hpet_msleep(size_t ms); + +/* + * Initialize the Local APIC driver + */ +int hpet_init(void); + +#endif /* !_CLKDEV_HPET_H_ */ -- cgit v1.2.3