diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/sys/include/io/ic/ahcivar.h | 41 | ||||
| -rw-r--r-- | src/sys/io/ic/ahci.c | 137 |
2 files changed, 177 insertions, 1 deletions
diff --git a/src/sys/include/io/ic/ahcivar.h b/src/sys/include/io/ic/ahcivar.h new file mode 100644 index 0000000..b045c9d --- /dev/null +++ b/src/sys/include/io/ic/ahcivar.h @@ -0,0 +1,41 @@ +/* + * Copyright (c) 2025 Ian Marco Moffett and L5 engineers + * 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 the project 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 _IC_AHCIVAR_H_ +#define _IC_AHCIVAR_H_ 1 + +#include <io/ic/ahciregs.h> + +struct ahci_hba { + volatile struct hba_memspace *io; +}; + +#define AHCI_TIMEOUT 500 + +#endif /* !_IC_AHCIVAR_H_ */ diff --git a/src/sys/io/ic/ahci.c b/src/sys/io/ic/ahci.c index 4515b9d..3d0e890 100644 --- a/src/sys/io/ic/ahci.c +++ b/src/sys/io/ic/ahci.c @@ -35,8 +35,14 @@ #include <sys/types.h> #include <sys/syslog.h> #include <sys/cdefs.h> +#include <sys/errno.h> #include <io/pci/pci.h> +#include <io/pci/bar.h> +#include <io/ic/ahciregs.h> +#include <io/ic/ahcivar.h> #include <os/module.h> +#include <os/clkdev.h> +#include <os/mmio.h> /* * Represents the PCI advocation descriptor for this @@ -44,6 +50,107 @@ */ static struct pci_adv driver; +/* Various other state */ +static struct pci_device dev; +static struct clkdev *clkdev; +static struct ahci_hba root_hba; + +/* + * Poll register to have 'bits' set/unset. + * + * @reg: Register to poll. + * @bits: Bits to be checked. + * @pollset: True to poll as set. + * + * Returns zero if the register updated in time, otherwise a less + * than zero value upon failure. + */ +static int +ahci_poll32(volatile uint32_t *reg, uint32_t bits, bool pollset) +{ + size_t usec_start, usec; + size_t elapsed_msec; + uint32_t val; + bool tmp; + + usec_start = clkdev->get_time_usec(); + for (;;) { + val = mmio_read32(reg); + tmp = (pollset) ? ISSET(val, bits) : !ISSET(val, bits); + + usec = clkdev->get_time_usec(); + elapsed_msec = (usec - usec_start) / 1000; + + /* If tmp is set, the register updated in time */ + if (tmp) { + break; + } + + /* Exit with an error if we timeout */ + if (elapsed_msec > AHCI_TIMEOUT) { + return -ETIME; + } + } + + return 0; +} + +/* + * Perform a full HBA reset by using the HR bit + * within the GHC register. + * + * See section 10.4.3 of the AHCI spec for more + * information. + */ +static int +ahci_hba_reset(struct ahci_hba *hba) +{ + volatile struct hba_memspace *io = hba->io; + uint32_t ghc; + int error; + + /* Begin the reset */ + ghc = mmio_read32(&io->ghc); + ghc |= AHCI_GHC_HR; + mmio_write32(&io->ghc, ghc); + + /* Wait until it is done */ + error = ahci_poll32(&io->ghc, AHCI_GHC_HR, false); + if (error < 0) { + printf("ahci: HBA reset timed out\n"); + return error; + } + + return 0; +} + +/* + * Put the HBA as well as its devices in an initialized + * state so that they may be used for operation. + */ +static int +ahci_hba_init(struct ahci_hba *hba) +{ + volatile struct hba_memspace *io = hba->io; + uint32_t ghc; + int error; + + /* Ensure the host controller is AHCI aware */ + ghc = mmio_read32(&io->ghc); + ghc |= AHCI_GHC_AE; + mmio_write32(&io->ghc, ghc); + + /* + * We cannot be so certain what state the BIOS or whatever + * firmware left the host controller in, therefore the HBA + * will require a reset so we can have it in a known state. + */ + if ((error = ahci_hba_reset(hba)) < 0) { + return error; + } + return 0; +} + /* * Initialize only the AHCI driver's state rather than * the hardware it covers. This is used so we can advertise @@ -52,12 +159,22 @@ static struct pci_adv driver; static int ahci_init(struct module *modp) { + uint16_t clkmask; int error; + clkmask = CLKDEV_MSLEEP | CLKDEV_GET_USEC; + error = clkdev_get(clkmask, &clkdev); + if (error < 0) { + printf("ahci_init: could not get clkdev\n"); + return error; + } + if ((error = pci_advoc(&driver)) < 0) { printf("ahci_init: failed to advocate for HBA\n"); return error; } + + root_hba.io = NULL; return 0; } @@ -68,8 +185,26 @@ ahci_init(struct module *modp) static int ahci_attach(struct pci_adv *adv) { + struct bus_space bs; + int error; + + /* Only call once */ + if (root_hba.io != NULL) { + return -EIO; + } + + dev = adv->lookup; printf("ahci: detected AHCI controller\n"); - return 0; + + /* Map ABAR */ + error = pci_map_bar(&dev, 5, &bs); + if (error < 0) { + printf("ahci: failed to map bar 5 (error=%d)\n", error); + return error; + } + + root_hba.io = (void *)bs.va_base; + return ahci_hba_init(&root_hba); } static struct pci_adv driver = { |