/*-
* SPDX-License-Identifier: BSD-2-Clause
*
* Copyright 2021 Jessica Clarke <jrtc27@FreeBSD.org>
*
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
*
*/
/* SiFive FU740 DesignWare PCIe driver */
#include <sys/cdefs.h>
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/gpio.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <sys/rman.h>
#include <machine/bus.h>
#include <machine/intr.h>
#include <machine/resource.h>
#include <dev/extres/clk/clk.h>
#include <dev/extres/hwreset/hwreset.h>
#include <dev/gpio/gpiobusvar.h>
#include <dev/ofw/ofw_bus.h>
#include <dev/ofw/ofw_bus_subr.h>
#include <dev/ofw/ofw_pci.h>
#include <dev/ofw/ofwpci.h>
#include <dev/pci/pcivar.h>
#include <dev/pci/pcireg.h>
#include <dev/pci/pcib_private.h>
#include <dev/pci/pci_dw.h>
#include "pcib_if.h"
#include "pci_dw_if.h"
#define FUDW_PHYS 2
#define FUDW_LANES_PER_PHY 4
#define FUDW_MGMT_PERST_N 0x0
#define FUDW_MGMT_LTSSM_EN 0x10
#define FUDW_MGMT_HOLD_PHY_RST 0x18
#define FUDW_MGMT_DEVICE_TYPE 0x708
#define FUDW_MGMT_DEVICE_TYPE_RC 0x4
#define FUDW_MGMT_PHY_CR_PARA_REG(_n, _r) \
(0x860 + (_n) * 0x40 + FUDW_MGMT_PHY_CR_PARA_##_r)
#define FUDW_MGMT_PHY_CR_PARA_ADDR 0x0
#define FUDW_MGMT_PHY_CR_PARA_READ_EN 0x10
#define FUDW_MGMT_PHY_CR_PARA_READ_DATA 0x18
#define FUDW_MGMT_PHY_CR_PARA_SEL 0x20
#define FUDW_MGMT_PHY_CR_PARA_WRITE_DATA 0x28
#define FUDW_MGMT_PHY_CR_PARA_WRITE_EN 0x30
#define FUDW_MGMT_PHY_CR_PARA_ACK 0x38
#define FUDW_MGMT_PHY_LANE(_n) (0x1008 + (_n) * 0x100)
#define FUDW_MGMT_PHY_LANE_CDR_TRACK_EN (1 << 0)
#define FUDW_MGMT_PHY_LANE_LOS_THRESH (1 << 5)
#define FUDW_MGMT_PHY_LANE_TERM_EN (1 << 9)
#define FUDW_MGMT_PHY_LANE_TERM_ACDC (1 << 10)
#define FUDW_MGMT_PHY_LANE_EN (1 << 11)
#define FUDW_MGMT_PHY_LANE_INIT \
(FUDW_MGMT_PHY_LANE_CDR_TRACK_EN | FUDW_MGMT_PHY_LANE_LOS_THRESH | \
FUDW_MGMT_PHY_LANE_TERM_EN | FUDW_MGMT_PHY_LANE_TERM_ACDC | \
FUDW_MGMT_PHY_LANE_EN)
#define FUDW_DBI_PORT_DBG1 0x72c
#define FUDW_DBI_PORT_DBG1_LINK_UP (1 << 4)
#define FUDW_DBI_PORT_DBG1_LINK_IN_TRAINING (1 << 29)
struct fupci_softc {
struct pci_dw_softc dw_sc;
device_t dev;
struct resource *mgmt_res;
gpio_pin_t porst_pin;
gpio_pin_t pwren_pin;
clk_t pcie_aux_clk;
hwreset_t pcie_aux_rst;
};
#define FUDW_MGMT_READ(_sc, _o) bus_read_4((_sc)->mgmt_res, (_o))
#define FUDW_MGMT_WRITE(_sc, _o, _v) bus_write_4((_sc)->mgmt_res, (_o), (_v))
static struct ofw_compat_data compat_data[] = {
{ "sifive,fu740-pcie", 1 },
{ NULL, 0 },
};
/* Currently unused; included for completeness */
static int __unused
fupci_phy_read(struct fupci_softc *sc, int phy, uint32_t reg, uint32_t *val)
{
unsigned timeout;
uint32_t ack;
FUDW_MGMT_WRITE(sc, FUDW_MGMT_PHY_CR_PARA_REG(phy, ADDR), reg);
FUDW_MGMT_WRITE(sc, FUDW_MGMT_PHY_CR_PARA_REG(phy, READ_EN), 1);
timeout = 10;
do {
ack = FUDW_MGMT_READ(sc, FUDW_MGMT_PHY_CR_PARA_REG(phy, ACK));
if (ack != 0)
break;
DELAY(10);
} while (--timeout > 0);
if (timeout == 0) {
device_printf(sc->dev, "Timeout waiting for read ACK\n");
return (ETIMEDOUT);
}
*val = FUDW_MGMT_READ(sc, FUDW_MGMT_PHY_CR_PARA_REG(phy, READ_DATA));
FUDW_MGMT_WRITE(sc, FUDW_MGMT_PHY_CR_PARA_REG(phy, READ_EN), 0);
timeout = 10;
do {
ack = FUDW_MGMT_READ(sc, FUDW_MGMT_PHY_CR_PARA_REG(phy, ACK));
if (ack == 0)
break;
DELAY(10);
} while (--timeout > 0);
if (timeout == 0) {
device_printf(sc->dev, "Timeout waiting for read un-ACK\n");
return (ETIMEDOUT);
}
return (0);
}
static int
fupci_phy_write(struct fupci_softc *sc, int phy, uint32_t reg, uint32_t val)
{
unsigned timeout;
uint32_t ack;
FUDW_MGMT_WRITE(sc, FUDW_MGMT_PHY_CR_PARA_REG(phy, ADDR), reg);
FUDW_MGMT_WRITE(sc, FUDW_MGMT_PHY_CR_PARA_REG(phy, WRITE_DATA), val);
FUDW_MGMT_WRITE(sc, FUDW_MGMT_PHY_CR_PARA_REG(phy, WRITE_EN), 1);
timeout = 10;
do {
ack = FUDW_MGMT_READ(sc, FUDW_MGMT_PHY_CR_PARA_REG(phy, ACK));
if (ack != 0)
break;
DELAY(10);
} while (--timeout > 0);
if (timeout == 0) {
device_printf(sc->dev, "Timeout waiting for write ACK\n");
return (ETIMEDOUT);
}
FUDW_MGMT_WRITE(sc, FUDW_MGMT_PHY_CR_PARA_REG(phy, WRITE_EN), 0);
timeout = 10;
do {
ack = FUDW_MGMT_READ(sc, FUDW_MGMT_PHY_CR_PARA_REG(phy, ACK));
if (ack == 0)
break;
DELAY(10);
} while (--timeout > 0);
if (timeout == 0) {
device_printf(sc->dev, "Timeout waiting for write un-ACK\n");
return (ETIMEDOUT);
}
return (0);
}
static int
fupci_phy_init(struct fupci_softc *sc)
{
device_t dev;
int error, phy, lane;
dev = sc->dev;
/* Assert core power-on reset (active low) */
error = gpio_pin_set_active(sc->porst_pin, false);
if (error != 0) {
device_printf(dev, "Cannot assert power-on reset: %d\n",
error);
return (error);
}
/* Assert PERST_N */
FUDW_MGMT_WRITE(sc, FUDW_MGMT_PERST_N, 0);
/* Enable power */
error = gpio_pin_set_active(sc->pwren_pin, true);
if (error != 0) {
device_printf(dev, "Cannot enable power: %d\n", error);
return (error);
}
/* Hold PERST for 100ms as per the PCIe spec */
DELAY(100);
/* Deassert PERST_N */
FUDW_MGMT_WRITE(sc, FUDW_MGMT_PERST_N, 1);
/* Deassert core power-on reset (active low) */
error = gpio_pin_set_active(sc->porst_pin, true);
if (error != 0) {
device_printf(dev, "Cannot deassert power-on reset: %d\n",
error);
return (error);
}
/* Enable the aux clock */
error = clk_enable(sc->pcie_aux_clk);
if (error != 0) {
device_printf(dev, "Cannot enable aux clock: %d\n", error);
return (error);
}
/* Hold LTSSM in reset whilst initialising the PHYs */
FUDW_MGMT_WRITE(sc, FUDW_MGMT_HOLD_PHY_RST, 1);
/* Deassert the aux reset */
error = hwreset_deassert(sc->pcie_aux_rst);
if (error != 0) {
device_printf(dev, "Cannot deassert aux reset: %d\n", error);
return (error);
}
/* Enable control register interface */
for (phy = 0; phy < FUDW_PHYS; ++phy)
FUDW_MGMT_WRITE(sc, FUDW_MGMT_PHY_CR_PARA_REG(phy, SEL), 1);
/* Wait for enable to take effect */
DELAY(1);
/* Initialise lane configuration */
for (phy = 0; phy < FUDW_PHYS; ++phy) {
for (lane = 0; lane < FUDW_LANES_PER_PHY; ++lane)
fupci_phy_write(sc, phy, FUDW_MGMT_PHY_LANE(lane),
FUDW_MGMT_PHY_LANE_INIT);
}
/* Disable the aux clock whilst taking the LTSSM out of reset */
error = clk_disable(sc->pcie_aux_clk);
if (error != 0) {
device_printf(dev, "Cannot disable aux clock: %d\n", error);
return (error);
}
/* Take LTSSM out of reset */
FUDW_MGMT_WRITE(sc, FUDW_MGMT_HOLD_PHY_RST, 0);
/* Enable the aux clock again */
error = clk_enable(sc->pcie_aux_clk);
if (error != 0) {
device_printf(dev, "Cannot re-enable aux clock: %d\n", error);
return (error);
}
/* Put the controller in Root Complex mode */
FUDW_MGMT_WRITE(sc, FUDW_MGMT_DEVICE_TYPE, FUDW_MGMT_DEVICE_TYPE_RC);
return (0);
}
static void
fupci_dbi_protect(struct fupci_softc *sc, bool protect)
{
uint32_t reg;
reg = pci_dw_dbi_rd4(sc->dev, DW_MISC_CONTROL_1);
if (protect)
reg &= ~DBI_RO_WR_EN;
else
reg |= DBI_RO_WR_EN;
pci_dw_dbi_wr4(sc->dev, DW_MISC_CONTROL_1, reg);
}
static int
fupci_init(struct fupci_softc *sc)
{
/* Enable 32-bit I/O window */
fupci_dbi_protect(sc, false);
pci_dw_dbi_wr2(sc->dev, PCIR_IOBASEL_1,
(PCIM_BRIO_32 << 8) | PCIM_BRIO_32);
fupci_dbi_protect(sc, true);
/* Enable LTSSM */
FUDW_MGMT_WRITE(sc, FUDW_MGMT_LTSSM_EN, 1);
return (0);
}
static int
fupci_probe(device_t dev)
{
if (!ofw_bus_status_okay(dev))
return (ENXIO);
if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0)
return (ENXIO);
device_set_desc(dev, "SiFive FU740 PCIe Controller");
return (BUS_PROBE_DEFAULT);
}
static int
fupci_attach(device_t dev)
{
struct fupci_softc *sc;
phandle_t node;
int error, rid;
sc = device_get_softc(dev);
node = ofw_bus_get_node(dev);
sc->dev = dev;
rid = 0;
error = ofw_bus_find_string_index(node, "reg-names", "dbi", &rid);
if (error != 0) {
device_printf(dev, "Cannot get DBI memory: %d\n", error);
goto fail;
}
sc->dw_sc.dbi_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
RF_ACTIVE);
if (sc->dw_sc.dbi_res == NULL) {
device_printf(dev, "Cannot allocate DBI memory\n");
error = ENXIO;
goto fail;
}
rid = 0;
error = ofw_bus_find_string_index(node, "reg-names", "mgmt", &rid);
if (error != 0) {
device_printf(dev, "Cannot get management space memory: %d\n",
error);
goto fail;
}
sc->mgmt_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
RF_ACTIVE);
if (sc->mgmt_res == NULL) {
device_printf(dev, "Cannot allocate management space memory\n");
error = ENXIO;
goto fail;
}
error = gpio_pin_get_by_ofw_property(dev, node, "reset-gpios",
&sc->porst_pin);
/* Old U-Boot device tree uses perstn-gpios */
if (error == ENOENT)
error = gpio_pin_get_by_ofw_property(dev, node, "perstn-gpios",
&sc->porst_pin);
if (error != 0) {
device_printf(dev, "Cannot get power-on reset GPIO: %d\n",
error);
goto fail;
}
error = gpio_pin_setflags(sc->porst_pin, GPIO_PIN_OUTPUT);
if (error != 0) {
device_printf(dev, "Cannot configure power-on reset GPIO: %d\n",
error);
goto fail;
}
error = gpio_pin_get_by_ofw_property(dev, node, "pwren-gpios",
&sc->pwren_pin);
if (error != 0) {
device_printf(dev, "Cannot get power enable GPIO: %d\n",
error);
goto fail;
}
error = gpio_pin_setflags(sc->pwren_pin, GPIO_PIN_OUTPUT);
if (error != 0) {
device_printf(dev, "Cannot configure power enable GPIO: %d\n",
error);
goto fail;
}
error = clk_get_by_ofw_name(dev, node, "pcie_aux", &sc->pcie_aux_clk);
/* Old U-Boot device tree uses pcieaux */
if (error == ENOENT)
error = clk_get_by_ofw_name(dev, node, "pcieaux",
&sc->pcie_aux_clk);
if (error != 0) {
device_printf(dev, "Cannot get aux clock: %d\n", error);
goto fail;
}
error = hwreset_get_by_ofw_idx(dev, node, 0, &sc->pcie_aux_rst);
if (error != 0) {
device_printf(dev, "Cannot get aux reset: %d\n", error);
goto fail;
}
error = fupci_phy_init(sc);
if (error != 0)
goto fail;
error = pci_dw_init(dev);
if (error != 0)
goto fail;
error = fupci_init(sc);
if (error != 0)
goto fail;
return (bus_generic_attach(dev));
fail:
/* XXX Cleanup */
return (error);
}
static int
fupci_get_link(device_t dev, bool *status)
{
uint32_t reg;
reg = pci_dw_dbi_rd4(dev, FUDW_DBI_PORT_DBG1);
*status = (reg & FUDW_DBI_PORT_DBG1_LINK_UP) != 0 &&
(reg & FUDW_DBI_PORT_DBG1_LINK_IN_TRAINING) == 0;
return (0);
}
static device_method_t fupci_methods[] = {
/* Device interface */
DEVMETHOD(device_probe, fupci_probe),
DEVMETHOD(device_attach, fupci_attach),
/* PCI DW interface */
DEVMETHOD(pci_dw_get_link, fupci_get_link),
DEVMETHOD_END
};
DEFINE_CLASS_1(pcib, fupci_driver, fupci_methods,
sizeof(struct fupci_softc), pci_dw_driver);
DRIVER_MODULE(fu740_pci_dw, simplebus, fupci_driver, NULL, NULL);