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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/ntb/hw/idt/ntb_hw_idt.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/ntb/hw/idt/ntb_hw_idt.c')
-rw-r--r-- | drivers/ntb/hw/idt/ntb_hw_idt.c | 2919 |
1 files changed, 2919 insertions, 0 deletions
diff --git a/drivers/ntb/hw/idt/ntb_hw_idt.c b/drivers/ntb/hw/idt/ntb_hw_idt.c new file mode 100644 index 000000000..51799fccf --- /dev/null +++ b/drivers/ntb/hw/idt/ntb_hw_idt.c @@ -0,0 +1,2919 @@ +/* + * This file is provided under a GPLv2 license. When using or + * redistributing this file, you may do so under that license. + * + * GPL LICENSE SUMMARY + * + * Copyright (C) 2016-2018 T-Platforms JSC All Rights Reserved. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General + * Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, one can be found http://www.gnu.org/licenses/. + * + * The full GNU General Public License is included in this distribution in + * the file called "COPYING". + * + * 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. + * + * IDT PCIe-switch NTB Linux driver + * + * Contact Information: + * Serge Semin <fancer.lancer@gmail.com>, <Sergey.Semin@t-platforms.ru> + */ + +#include <linux/stddef.h> +#include <linux/types.h> +#include <linux/kernel.h> +#include <linux/bitops.h> +#include <linux/sizes.h> +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/spinlock.h> +#include <linux/mutex.h> +#include <linux/pci.h> +#include <linux/aer.h> +#include <linux/slab.h> +#include <linux/list.h> +#include <linux/debugfs.h> +#include <linux/hwmon.h> +#include <linux/hwmon-sysfs.h> +#include <linux/ntb.h> + +#include "ntb_hw_idt.h" + +#define NTB_NAME "ntb_hw_idt" +#define NTB_DESC "IDT PCI-E Non-Transparent Bridge Driver" +#define NTB_VER "2.0" +#define NTB_IRQNAME "ntb_irq_idt" + +MODULE_DESCRIPTION(NTB_DESC); +MODULE_VERSION(NTB_VER); +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("T-platforms"); + +/* + * NT Endpoint registers table simplifying a loop access to the functionally + * related registers + */ +static const struct idt_ntb_regs ntdata_tbl = { + { {IDT_NT_BARSETUP0, IDT_NT_BARLIMIT0, + IDT_NT_BARLTBASE0, IDT_NT_BARUTBASE0}, + {IDT_NT_BARSETUP1, IDT_NT_BARLIMIT1, + IDT_NT_BARLTBASE1, IDT_NT_BARUTBASE1}, + {IDT_NT_BARSETUP2, IDT_NT_BARLIMIT2, + IDT_NT_BARLTBASE2, IDT_NT_BARUTBASE2}, + {IDT_NT_BARSETUP3, IDT_NT_BARLIMIT3, + IDT_NT_BARLTBASE3, IDT_NT_BARUTBASE3}, + {IDT_NT_BARSETUP4, IDT_NT_BARLIMIT4, + IDT_NT_BARLTBASE4, IDT_NT_BARUTBASE4}, + {IDT_NT_BARSETUP5, IDT_NT_BARLIMIT5, + IDT_NT_BARLTBASE5, IDT_NT_BARUTBASE5} }, + { {IDT_NT_INMSG0, IDT_NT_OUTMSG0, IDT_NT_INMSGSRC0}, + {IDT_NT_INMSG1, IDT_NT_OUTMSG1, IDT_NT_INMSGSRC1}, + {IDT_NT_INMSG2, IDT_NT_OUTMSG2, IDT_NT_INMSGSRC2}, + {IDT_NT_INMSG3, IDT_NT_OUTMSG3, IDT_NT_INMSGSRC3} } +}; + +/* + * NT Endpoint ports data table with the corresponding pcie command, link + * status, control and BAR-related registers + */ +static const struct idt_ntb_port portdata_tbl[IDT_MAX_NR_PORTS] = { +/*0*/ { IDT_SW_NTP0_PCIECMDSTS, IDT_SW_NTP0_PCIELCTLSTS, + IDT_SW_NTP0_NTCTL, + IDT_SW_SWPORT0CTL, IDT_SW_SWPORT0STS, + { {IDT_SW_NTP0_BARSETUP0, IDT_SW_NTP0_BARLIMIT0, + IDT_SW_NTP0_BARLTBASE0, IDT_SW_NTP0_BARUTBASE0}, + {IDT_SW_NTP0_BARSETUP1, IDT_SW_NTP0_BARLIMIT1, + IDT_SW_NTP0_BARLTBASE1, IDT_SW_NTP0_BARUTBASE1}, + {IDT_SW_NTP0_BARSETUP2, IDT_SW_NTP0_BARLIMIT2, + IDT_SW_NTP0_BARLTBASE2, IDT_SW_NTP0_BARUTBASE2}, + {IDT_SW_NTP0_BARSETUP3, IDT_SW_NTP0_BARLIMIT3, + IDT_SW_NTP0_BARLTBASE3, IDT_SW_NTP0_BARUTBASE3}, + {IDT_SW_NTP0_BARSETUP4, IDT_SW_NTP0_BARLIMIT4, + IDT_SW_NTP0_BARLTBASE4, IDT_SW_NTP0_BARUTBASE4}, + {IDT_SW_NTP0_BARSETUP5, IDT_SW_NTP0_BARLIMIT5, + IDT_SW_NTP0_BARLTBASE5, IDT_SW_NTP0_BARUTBASE5} } }, +/*1*/ {0}, +/*2*/ { IDT_SW_NTP2_PCIECMDSTS, IDT_SW_NTP2_PCIELCTLSTS, + IDT_SW_NTP2_NTCTL, + IDT_SW_SWPORT2CTL, IDT_SW_SWPORT2STS, + { {IDT_SW_NTP2_BARSETUP0, IDT_SW_NTP2_BARLIMIT0, + IDT_SW_NTP2_BARLTBASE0, IDT_SW_NTP2_BARUTBASE0}, + {IDT_SW_NTP2_BARSETUP1, IDT_SW_NTP2_BARLIMIT1, + IDT_SW_NTP2_BARLTBASE1, IDT_SW_NTP2_BARUTBASE1}, + {IDT_SW_NTP2_BARSETUP2, IDT_SW_NTP2_BARLIMIT2, + IDT_SW_NTP2_BARLTBASE2, IDT_SW_NTP2_BARUTBASE2}, + {IDT_SW_NTP2_BARSETUP3, IDT_SW_NTP2_BARLIMIT3, + IDT_SW_NTP2_BARLTBASE3, IDT_SW_NTP2_BARUTBASE3}, + {IDT_SW_NTP2_BARSETUP4, IDT_SW_NTP2_BARLIMIT4, + IDT_SW_NTP2_BARLTBASE4, IDT_SW_NTP2_BARUTBASE4}, + {IDT_SW_NTP2_BARSETUP5, IDT_SW_NTP2_BARLIMIT5, + IDT_SW_NTP2_BARLTBASE5, IDT_SW_NTP2_BARUTBASE5} } }, +/*3*/ {0}, +/*4*/ { IDT_SW_NTP4_PCIECMDSTS, IDT_SW_NTP4_PCIELCTLSTS, + IDT_SW_NTP4_NTCTL, + IDT_SW_SWPORT4CTL, IDT_SW_SWPORT4STS, + { {IDT_SW_NTP4_BARSETUP0, IDT_SW_NTP4_BARLIMIT0, + IDT_SW_NTP4_BARLTBASE0, IDT_SW_NTP4_BARUTBASE0}, + {IDT_SW_NTP4_BARSETUP1, IDT_SW_NTP4_BARLIMIT1, + IDT_SW_NTP4_BARLTBASE1, IDT_SW_NTP4_BARUTBASE1}, + {IDT_SW_NTP4_BARSETUP2, IDT_SW_NTP4_BARLIMIT2, + IDT_SW_NTP4_BARLTBASE2, IDT_SW_NTP4_BARUTBASE2}, + {IDT_SW_NTP4_BARSETUP3, IDT_SW_NTP4_BARLIMIT3, + IDT_SW_NTP4_BARLTBASE3, IDT_SW_NTP4_BARUTBASE3}, + {IDT_SW_NTP4_BARSETUP4, IDT_SW_NTP4_BARLIMIT4, + IDT_SW_NTP4_BARLTBASE4, IDT_SW_NTP4_BARUTBASE4}, + {IDT_SW_NTP4_BARSETUP5, IDT_SW_NTP4_BARLIMIT5, + IDT_SW_NTP4_BARLTBASE5, IDT_SW_NTP4_BARUTBASE5} } }, +/*5*/ {0}, +/*6*/ { IDT_SW_NTP6_PCIECMDSTS, IDT_SW_NTP6_PCIELCTLSTS, + IDT_SW_NTP6_NTCTL, + IDT_SW_SWPORT6CTL, IDT_SW_SWPORT6STS, + { {IDT_SW_NTP6_BARSETUP0, IDT_SW_NTP6_BARLIMIT0, + IDT_SW_NTP6_BARLTBASE0, IDT_SW_NTP6_BARUTBASE0}, + {IDT_SW_NTP6_BARSETUP1, IDT_SW_NTP6_BARLIMIT1, + IDT_SW_NTP6_BARLTBASE1, IDT_SW_NTP6_BARUTBASE1}, + {IDT_SW_NTP6_BARSETUP2, IDT_SW_NTP6_BARLIMIT2, + IDT_SW_NTP6_BARLTBASE2, IDT_SW_NTP6_BARUTBASE2}, + {IDT_SW_NTP6_BARSETUP3, IDT_SW_NTP6_BARLIMIT3, + IDT_SW_NTP6_BARLTBASE3, IDT_SW_NTP6_BARUTBASE3}, + {IDT_SW_NTP6_BARSETUP4, IDT_SW_NTP6_BARLIMIT4, + IDT_SW_NTP6_BARLTBASE4, IDT_SW_NTP6_BARUTBASE4}, + {IDT_SW_NTP6_BARSETUP5, IDT_SW_NTP6_BARLIMIT5, + IDT_SW_NTP6_BARLTBASE5, IDT_SW_NTP6_BARUTBASE5} } }, +/*7*/ {0}, +/*8*/ { IDT_SW_NTP8_PCIECMDSTS, IDT_SW_NTP8_PCIELCTLSTS, + IDT_SW_NTP8_NTCTL, + IDT_SW_SWPORT8CTL, IDT_SW_SWPORT8STS, + { {IDT_SW_NTP8_BARSETUP0, IDT_SW_NTP8_BARLIMIT0, + IDT_SW_NTP8_BARLTBASE0, IDT_SW_NTP8_BARUTBASE0}, + {IDT_SW_NTP8_BARSETUP1, IDT_SW_NTP8_BARLIMIT1, + IDT_SW_NTP8_BARLTBASE1, IDT_SW_NTP8_BARUTBASE1}, + {IDT_SW_NTP8_BARSETUP2, IDT_SW_NTP8_BARLIMIT2, + IDT_SW_NTP8_BARLTBASE2, IDT_SW_NTP8_BARUTBASE2}, + {IDT_SW_NTP8_BARSETUP3, IDT_SW_NTP8_BARLIMIT3, + IDT_SW_NTP8_BARLTBASE3, IDT_SW_NTP8_BARUTBASE3}, + {IDT_SW_NTP8_BARSETUP4, IDT_SW_NTP8_BARLIMIT4, + IDT_SW_NTP8_BARLTBASE4, IDT_SW_NTP8_BARUTBASE4}, + {IDT_SW_NTP8_BARSETUP5, IDT_SW_NTP8_BARLIMIT5, + IDT_SW_NTP8_BARLTBASE5, IDT_SW_NTP8_BARUTBASE5} } }, +/*9*/ {0}, +/*10*/ {0}, +/*11*/ {0}, +/*12*/ { IDT_SW_NTP12_PCIECMDSTS, IDT_SW_NTP12_PCIELCTLSTS, + IDT_SW_NTP12_NTCTL, + IDT_SW_SWPORT12CTL, IDT_SW_SWPORT12STS, + { {IDT_SW_NTP12_BARSETUP0, IDT_SW_NTP12_BARLIMIT0, + IDT_SW_NTP12_BARLTBASE0, IDT_SW_NTP12_BARUTBASE0}, + {IDT_SW_NTP12_BARSETUP1, IDT_SW_NTP12_BARLIMIT1, + IDT_SW_NTP12_BARLTBASE1, IDT_SW_NTP12_BARUTBASE1}, + {IDT_SW_NTP12_BARSETUP2, IDT_SW_NTP12_BARLIMIT2, + IDT_SW_NTP12_BARLTBASE2, IDT_SW_NTP12_BARUTBASE2}, + {IDT_SW_NTP12_BARSETUP3, IDT_SW_NTP12_BARLIMIT3, + IDT_SW_NTP12_BARLTBASE3, IDT_SW_NTP12_BARUTBASE3}, + {IDT_SW_NTP12_BARSETUP4, IDT_SW_NTP12_BARLIMIT4, + IDT_SW_NTP12_BARLTBASE4, IDT_SW_NTP12_BARUTBASE4}, + {IDT_SW_NTP12_BARSETUP5, IDT_SW_NTP12_BARLIMIT5, + IDT_SW_NTP12_BARLTBASE5, IDT_SW_NTP12_BARUTBASE5} } }, +/*13*/ {0}, +/*14*/ {0}, +/*15*/ {0}, +/*16*/ { IDT_SW_NTP16_PCIECMDSTS, IDT_SW_NTP16_PCIELCTLSTS, + IDT_SW_NTP16_NTCTL, + IDT_SW_SWPORT16CTL, IDT_SW_SWPORT16STS, + { {IDT_SW_NTP16_BARSETUP0, IDT_SW_NTP16_BARLIMIT0, + IDT_SW_NTP16_BARLTBASE0, IDT_SW_NTP16_BARUTBASE0}, + {IDT_SW_NTP16_BARSETUP1, IDT_SW_NTP16_BARLIMIT1, + IDT_SW_NTP16_BARLTBASE1, IDT_SW_NTP16_BARUTBASE1}, + {IDT_SW_NTP16_BARSETUP2, IDT_SW_NTP16_BARLIMIT2, + IDT_SW_NTP16_BARLTBASE2, IDT_SW_NTP16_BARUTBASE2}, + {IDT_SW_NTP16_BARSETUP3, IDT_SW_NTP16_BARLIMIT3, + IDT_SW_NTP16_BARLTBASE3, IDT_SW_NTP16_BARUTBASE3}, + {IDT_SW_NTP16_BARSETUP4, IDT_SW_NTP16_BARLIMIT4, + IDT_SW_NTP16_BARLTBASE4, IDT_SW_NTP16_BARUTBASE4}, + {IDT_SW_NTP16_BARSETUP5, IDT_SW_NTP16_BARLIMIT5, + IDT_SW_NTP16_BARLTBASE5, IDT_SW_NTP16_BARUTBASE5} } }, +/*17*/ {0}, +/*18*/ {0}, +/*19*/ {0}, +/*20*/ { IDT_SW_NTP20_PCIECMDSTS, IDT_SW_NTP20_PCIELCTLSTS, + IDT_SW_NTP20_NTCTL, + IDT_SW_SWPORT20CTL, IDT_SW_SWPORT20STS, + { {IDT_SW_NTP20_BARSETUP0, IDT_SW_NTP20_BARLIMIT0, + IDT_SW_NTP20_BARLTBASE0, IDT_SW_NTP20_BARUTBASE0}, + {IDT_SW_NTP20_BARSETUP1, IDT_SW_NTP20_BARLIMIT1, + IDT_SW_NTP20_BARLTBASE1, IDT_SW_NTP20_BARUTBASE1}, + {IDT_SW_NTP20_BARSETUP2, IDT_SW_NTP20_BARLIMIT2, + IDT_SW_NTP20_BARLTBASE2, IDT_SW_NTP20_BARUTBASE2}, + {IDT_SW_NTP20_BARSETUP3, IDT_SW_NTP20_BARLIMIT3, + IDT_SW_NTP20_BARLTBASE3, IDT_SW_NTP20_BARUTBASE3}, + {IDT_SW_NTP20_BARSETUP4, IDT_SW_NTP20_BARLIMIT4, + IDT_SW_NTP20_BARLTBASE4, IDT_SW_NTP20_BARUTBASE4}, + {IDT_SW_NTP20_BARSETUP5, IDT_SW_NTP20_BARLIMIT5, + IDT_SW_NTP20_BARLTBASE5, IDT_SW_NTP20_BARUTBASE5} } }, +/*21*/ {0}, +/*22*/ {0}, +/*23*/ {0} +}; + +/* + * IDT PCIe-switch partitions table with the corresponding control, status + * and messages control registers + */ +static const struct idt_ntb_part partdata_tbl[IDT_MAX_NR_PARTS] = { +/*0*/ { IDT_SW_SWPART0CTL, IDT_SW_SWPART0STS, + {IDT_SW_SWP0MSGCTL0, IDT_SW_SWP0MSGCTL1, + IDT_SW_SWP0MSGCTL2, IDT_SW_SWP0MSGCTL3} }, +/*1*/ { IDT_SW_SWPART1CTL, IDT_SW_SWPART1STS, + {IDT_SW_SWP1MSGCTL0, IDT_SW_SWP1MSGCTL1, + IDT_SW_SWP1MSGCTL2, IDT_SW_SWP1MSGCTL3} }, +/*2*/ { IDT_SW_SWPART2CTL, IDT_SW_SWPART2STS, + {IDT_SW_SWP2MSGCTL0, IDT_SW_SWP2MSGCTL1, + IDT_SW_SWP2MSGCTL2, IDT_SW_SWP2MSGCTL3} }, +/*3*/ { IDT_SW_SWPART3CTL, IDT_SW_SWPART3STS, + {IDT_SW_SWP3MSGCTL0, IDT_SW_SWP3MSGCTL1, + IDT_SW_SWP3MSGCTL2, IDT_SW_SWP3MSGCTL3} }, +/*4*/ { IDT_SW_SWPART4CTL, IDT_SW_SWPART4STS, + {IDT_SW_SWP4MSGCTL0, IDT_SW_SWP4MSGCTL1, + IDT_SW_SWP4MSGCTL2, IDT_SW_SWP4MSGCTL3} }, +/*5*/ { IDT_SW_SWPART5CTL, IDT_SW_SWPART5STS, + {IDT_SW_SWP5MSGCTL0, IDT_SW_SWP5MSGCTL1, + IDT_SW_SWP5MSGCTL2, IDT_SW_SWP5MSGCTL3} }, +/*6*/ { IDT_SW_SWPART6CTL, IDT_SW_SWPART6STS, + {IDT_SW_SWP6MSGCTL0, IDT_SW_SWP6MSGCTL1, + IDT_SW_SWP6MSGCTL2, IDT_SW_SWP6MSGCTL3} }, +/*7*/ { IDT_SW_SWPART7CTL, IDT_SW_SWPART7STS, + {IDT_SW_SWP7MSGCTL0, IDT_SW_SWP7MSGCTL1, + IDT_SW_SWP7MSGCTL2, IDT_SW_SWP7MSGCTL3} } +}; + +/* + * DebugFS directory to place the driver debug file + */ +static struct dentry *dbgfs_topdir; + +/*============================================================================= + * 1. IDT PCIe-switch registers IO-functions + * + * Beside ordinary configuration space registers IDT PCIe-switch expose + * global configuration registers, which are used to determine state of other + * device ports as well as being notified of some switch-related events. + * Additionally all the configuration space registers of all the IDT + * PCIe-switch functions are mapped to the Global Address space, so each + * function can determine a configuration of any other PCI-function. + * Functions declared in this chapter are created to encapsulate access + * to configuration and global registers, so the driver code just need to + * provide IDT NTB hardware descriptor and a register address. + *============================================================================= + */ + +/* + * idt_nt_write() - PCI configuration space registers write method + * @ndev: IDT NTB hardware driver descriptor + * @reg: Register to write data to + * @data: Value to write to the register + * + * IDT PCIe-switch registers are all Little endian. + */ +static void idt_nt_write(struct idt_ntb_dev *ndev, + const unsigned int reg, const u32 data) +{ + /* + * It's obvious bug to request a register exceeding the maximum possible + * value as well as to have it unaligned. + */ + if (WARN_ON(reg > IDT_REG_PCI_MAX || !IS_ALIGNED(reg, IDT_REG_ALIGN))) + return; + + /* Just write the value to the specified register */ + iowrite32(data, ndev->cfgspc + (ptrdiff_t)reg); +} + +/* + * idt_nt_read() - PCI configuration space registers read method + * @ndev: IDT NTB hardware driver descriptor + * @reg: Register to write data to + * + * IDT PCIe-switch Global configuration registers are all Little endian. + * + * Return: register value + */ +static u32 idt_nt_read(struct idt_ntb_dev *ndev, const unsigned int reg) +{ + /* + * It's obvious bug to request a register exceeding the maximum possible + * value as well as to have it unaligned. + */ + if (WARN_ON(reg > IDT_REG_PCI_MAX || !IS_ALIGNED(reg, IDT_REG_ALIGN))) + return ~0; + + /* Just read the value from the specified register */ + return ioread32(ndev->cfgspc + (ptrdiff_t)reg); +} + +/* + * idt_sw_write() - Global registers write method + * @ndev: IDT NTB hardware driver descriptor + * @reg: Register to write data to + * @data: Value to write to the register + * + * IDT PCIe-switch Global configuration registers are all Little endian. + */ +static void idt_sw_write(struct idt_ntb_dev *ndev, + const unsigned int reg, const u32 data) +{ + unsigned long irqflags; + + /* + * It's obvious bug to request a register exceeding the maximum possible + * value as well as to have it unaligned. + */ + if (WARN_ON(reg > IDT_REG_SW_MAX || !IS_ALIGNED(reg, IDT_REG_ALIGN))) + return; + + /* Lock GASA registers operations */ + spin_lock_irqsave(&ndev->gasa_lock, irqflags); + /* Set the global register address */ + iowrite32((u32)reg, ndev->cfgspc + (ptrdiff_t)IDT_NT_GASAADDR); + /* Put the new value of the register */ + iowrite32(data, ndev->cfgspc + (ptrdiff_t)IDT_NT_GASADATA); + /* Unlock GASA registers operations */ + spin_unlock_irqrestore(&ndev->gasa_lock, irqflags); +} + +/* + * idt_sw_read() - Global registers read method + * @ndev: IDT NTB hardware driver descriptor + * @reg: Register to write data to + * + * IDT PCIe-switch Global configuration registers are all Little endian. + * + * Return: register value + */ +static u32 idt_sw_read(struct idt_ntb_dev *ndev, const unsigned int reg) +{ + unsigned long irqflags; + u32 data; + + /* + * It's obvious bug to request a register exceeding the maximum possible + * value as well as to have it unaligned. + */ + if (WARN_ON(reg > IDT_REG_SW_MAX || !IS_ALIGNED(reg, IDT_REG_ALIGN))) + return ~0; + + /* Lock GASA registers operations */ + spin_lock_irqsave(&ndev->gasa_lock, irqflags); + /* Set the global register address */ + iowrite32((u32)reg, ndev->cfgspc + (ptrdiff_t)IDT_NT_GASAADDR); + /* Get the data of the register (read ops acts as MMIO barrier) */ + data = ioread32(ndev->cfgspc + (ptrdiff_t)IDT_NT_GASADATA); + /* Unlock GASA registers operations */ + spin_unlock_irqrestore(&ndev->gasa_lock, irqflags); + + return data; +} + +/* + * idt_reg_set_bits() - set bits of a passed register + * @ndev: IDT NTB hardware driver descriptor + * @reg: Register to change bits of + * @reg_lock: Register access spin lock + * @valid_mask: Mask of valid bits + * @set_bits: Bitmask to set + * + * Helper method to check whether a passed bitfield is valid and set + * corresponding bits of a register. + * + * WARNING! Make sure the passed register isn't accessed over plane + * idt_nt_write() method (read method is ok to be used concurrently). + * + * Return: zero on success, negative error on invalid bitmask. + */ +static inline int idt_reg_set_bits(struct idt_ntb_dev *ndev, unsigned int reg, + spinlock_t *reg_lock, + u64 valid_mask, u64 set_bits) +{ + unsigned long irqflags; + u32 data; + + if (set_bits & ~(u64)valid_mask) + return -EINVAL; + + /* Lock access to the register unless the change is written back */ + spin_lock_irqsave(reg_lock, irqflags); + data = idt_nt_read(ndev, reg) | (u32)set_bits; + idt_nt_write(ndev, reg, data); + /* Unlock the register */ + spin_unlock_irqrestore(reg_lock, irqflags); + + return 0; +} + +/* + * idt_reg_clear_bits() - clear bits of a passed register + * @ndev: IDT NTB hardware driver descriptor + * @reg: Register to change bits of + * @reg_lock: Register access spin lock + * @set_bits: Bitmask to clear + * + * Helper method to check whether a passed bitfield is valid and clear + * corresponding bits of a register. + * + * NOTE! Invalid bits are always considered cleared so it's not an error + * to clear them over. + * + * WARNING! Make sure the passed register isn't accessed over plane + * idt_nt_write() method (read method is ok to use concurrently). + */ +static inline void idt_reg_clear_bits(struct idt_ntb_dev *ndev, + unsigned int reg, spinlock_t *reg_lock, + u64 clear_bits) +{ + unsigned long irqflags; + u32 data; + + /* Lock access to the register unless the change is written back */ + spin_lock_irqsave(reg_lock, irqflags); + data = idt_nt_read(ndev, reg) & ~(u32)clear_bits; + idt_nt_write(ndev, reg, data); + /* Unlock the register */ + spin_unlock_irqrestore(reg_lock, irqflags); +} + +/*=========================================================================== + * 2. Ports operations + * + * IDT PCIe-switches can have from 3 up to 8 ports with possible + * NT-functions enabled. So all the possible ports need to be scanned looking + * for NTB activated. NTB API will have enumerated only the ports with NTB. + *=========================================================================== + */ + +/* + * idt_scan_ports() - scan IDT PCIe-switch ports collecting info in the tables + * @ndev: Pointer to the PCI device descriptor + * + * Return: zero on success, otherwise a negative error number. + */ +static int idt_scan_ports(struct idt_ntb_dev *ndev) +{ + unsigned char pidx, port, part; + u32 data, portsts, partsts; + + /* Retrieve the local port number */ + data = idt_nt_read(ndev, IDT_NT_PCIELCAP); + ndev->port = GET_FIELD(PCIELCAP_PORTNUM, data); + + /* Retrieve the local partition number */ + portsts = idt_sw_read(ndev, portdata_tbl[ndev->port].sts); + ndev->part = GET_FIELD(SWPORTxSTS_SWPART, portsts); + + /* Initialize port/partition -> index tables with invalid values */ + memset(ndev->port_idx_map, -EINVAL, sizeof(ndev->port_idx_map)); + memset(ndev->part_idx_map, -EINVAL, sizeof(ndev->part_idx_map)); + + /* + * Walk over all the possible ports checking whether any of them has + * NT-function activated + */ + ndev->peer_cnt = 0; + for (pidx = 0; pidx < ndev->swcfg->port_cnt; pidx++) { + port = ndev->swcfg->ports[pidx]; + /* Skip local port */ + if (port == ndev->port) + continue; + + /* Read the port status register to get it partition */ + portsts = idt_sw_read(ndev, portdata_tbl[port].sts); + part = GET_FIELD(SWPORTxSTS_SWPART, portsts); + + /* Retrieve the partition status */ + partsts = idt_sw_read(ndev, partdata_tbl[part].sts); + /* Check if partition state is active and port has NTB */ + if (IS_FLD_SET(SWPARTxSTS_STATE, partsts, ACT) && + (IS_FLD_SET(SWPORTxSTS_MODE, portsts, NT) || + IS_FLD_SET(SWPORTxSTS_MODE, portsts, USNT) || + IS_FLD_SET(SWPORTxSTS_MODE, portsts, USNTDMA) || + IS_FLD_SET(SWPORTxSTS_MODE, portsts, NTDMA))) { + /* Save the port and partition numbers */ + ndev->peers[ndev->peer_cnt].port = port; + ndev->peers[ndev->peer_cnt].part = part; + /* Fill in the port/partition -> index tables */ + ndev->port_idx_map[port] = ndev->peer_cnt; + ndev->part_idx_map[part] = ndev->peer_cnt; + ndev->peer_cnt++; + } + } + + dev_dbg(&ndev->ntb.pdev->dev, "Local port: %hhu, num of peers: %hhu\n", + ndev->port, ndev->peer_cnt); + + /* It's useless to have this driver loaded if there is no any peer */ + if (ndev->peer_cnt == 0) { + dev_warn(&ndev->ntb.pdev->dev, "No active peer found\n"); + return -ENODEV; + } + + return 0; +} + +/* + * idt_ntb_port_number() - get the local port number + * @ntb: NTB device context. + * + * Return: the local port number + */ +static int idt_ntb_port_number(struct ntb_dev *ntb) +{ + struct idt_ntb_dev *ndev = to_ndev_ntb(ntb); + + return ndev->port; +} + +/* + * idt_ntb_peer_port_count() - get the number of peer ports + * @ntb: NTB device context. + * + * Return the count of detected peer NT-functions. + * + * Return: number of peer ports + */ +static int idt_ntb_peer_port_count(struct ntb_dev *ntb) +{ + struct idt_ntb_dev *ndev = to_ndev_ntb(ntb); + + return ndev->peer_cnt; +} + +/* + * idt_ntb_peer_port_number() - get peer port by given index + * @ntb: NTB device context. + * @pidx: Peer port index. + * + * Return: peer port or negative error + */ +static int idt_ntb_peer_port_number(struct ntb_dev *ntb, int pidx) +{ + struct idt_ntb_dev *ndev = to_ndev_ntb(ntb); + + if (pidx < 0 || ndev->peer_cnt <= pidx) + return -EINVAL; + + /* Return the detected NT-function port number */ + return ndev->peers[pidx].port; +} + +/* + * idt_ntb_peer_port_idx() - get peer port index by given port number + * @ntb: NTB device context. + * @port: Peer port number. + * + * Internal port -> index table is pre-initialized with -EINVAL values, + * so we just need to return it value + * + * Return: peer NT-function port index or negative error + */ +static int idt_ntb_peer_port_idx(struct ntb_dev *ntb, int port) +{ + struct idt_ntb_dev *ndev = to_ndev_ntb(ntb); + + if (port < 0 || IDT_MAX_NR_PORTS <= port) + return -EINVAL; + + return ndev->port_idx_map[port]; +} + +/*=========================================================================== + * 3. Link status operations + * There is no any ready-to-use method to have peer ports notified if NTB + * link is set up or got down. Instead global signal can be used instead. + * In case if any one of ports changes local NTB link state, it sends + * global signal and clears corresponding global state bit. Then all the ports + * receive a notification of that, so to make client driver being aware of + * possible NTB link change. + * Additionally each of active NT-functions is subscribed to PCIe-link + * state changes of peer ports. + *=========================================================================== + */ + +static void idt_ntb_local_link_disable(struct idt_ntb_dev *ndev); + +/* + * idt_init_link() - Initialize NTB link state notification subsystem + * @ndev: IDT NTB hardware driver descriptor + * + * Function performs the basic initialization of some global registers + * needed to enable IRQ-based notifications of PCIe Link Up/Down and + * Global Signal events. + * NOTE Since it's not possible to determine when all the NTB peer drivers are + * unloaded as well as have those registers accessed concurrently, we must + * preinitialize them with the same value and leave it uncleared on local + * driver unload. + */ +static void idt_init_link(struct idt_ntb_dev *ndev) +{ + u32 part_mask, port_mask, se_mask; + unsigned char pidx; + + /* Initialize spin locker of Mapping Table access registers */ + spin_lock_init(&ndev->mtbl_lock); + + /* Walk over all detected peers collecting port and partition masks */ + port_mask = ~BIT(ndev->port); + part_mask = ~BIT(ndev->part); + for (pidx = 0; pidx < ndev->peer_cnt; pidx++) { + port_mask &= ~BIT(ndev->peers[pidx].port); + part_mask &= ~BIT(ndev->peers[pidx].part); + } + + /* Clean the Link Up/Down and GLobal Signal status registers */ + idt_sw_write(ndev, IDT_SW_SELINKUPSTS, (u32)-1); + idt_sw_write(ndev, IDT_SW_SELINKDNSTS, (u32)-1); + idt_sw_write(ndev, IDT_SW_SEGSIGSTS, (u32)-1); + + /* Unmask NT-activated partitions to receive Global Switch events */ + idt_sw_write(ndev, IDT_SW_SEPMSK, part_mask); + + /* Enable PCIe Link Up events of NT-activated ports */ + idt_sw_write(ndev, IDT_SW_SELINKUPMSK, port_mask); + + /* Enable PCIe Link Down events of NT-activated ports */ + idt_sw_write(ndev, IDT_SW_SELINKDNMSK, port_mask); + + /* Unmask NT-activated partitions to receive Global Signal events */ + idt_sw_write(ndev, IDT_SW_SEGSIGMSK, part_mask); + + /* Unmask Link Up/Down and Global Switch Events */ + se_mask = ~(IDT_SEMSK_LINKUP | IDT_SEMSK_LINKDN | IDT_SEMSK_GSIGNAL); + idt_sw_write(ndev, IDT_SW_SEMSK, se_mask); + + dev_dbg(&ndev->ntb.pdev->dev, "NTB link status events initialized"); +} + +/* + * idt_deinit_link() - deinitialize link subsystem + * @ndev: IDT NTB hardware driver descriptor + * + * Just disable the link back. + */ +static void idt_deinit_link(struct idt_ntb_dev *ndev) +{ + /* Disable the link */ + idt_ntb_local_link_disable(ndev); + + dev_dbg(&ndev->ntb.pdev->dev, "NTB link status events deinitialized"); +} + +/* + * idt_se_isr() - switch events ISR + * @ndev: IDT NTB hardware driver descriptor + * @ntint_sts: NT-function interrupt status + * + * This driver doesn't support IDT PCIe-switch dynamic reconfigurations, + * Failover capability, etc, so switch events are utilized to notify of + * PCIe and NTB link events. + * The method is called from PCIe ISR bottom-half routine. + */ +static void idt_se_isr(struct idt_ntb_dev *ndev, u32 ntint_sts) +{ + u32 sests; + + /* Read Switch Events status */ + sests = idt_sw_read(ndev, IDT_SW_SESTS); + + /* Clean the Link Up/Down and Global Signal status registers */ + idt_sw_write(ndev, IDT_SW_SELINKUPSTS, (u32)-1); + idt_sw_write(ndev, IDT_SW_SELINKDNSTS, (u32)-1); + idt_sw_write(ndev, IDT_SW_SEGSIGSTS, (u32)-1); + + /* Clean the corresponding interrupt bit */ + idt_nt_write(ndev, IDT_NT_NTINTSTS, IDT_NTINTSTS_SEVENT); + + dev_dbg(&ndev->ntb.pdev->dev, "SE IRQ detected %#08x (SESTS %#08x)", + ntint_sts, sests); + + /* Notify the client driver of possible link state change */ + ntb_link_event(&ndev->ntb); +} + +/* + * idt_ntb_local_link_enable() - enable the local NTB link. + * @ndev: IDT NTB hardware driver descriptor + * + * In order to enable the NTB link we need: + * - enable Completion TLPs translation + * - initialize mapping table to enable the Request ID translation + * - notify peers of NTB link state change + */ +static void idt_ntb_local_link_enable(struct idt_ntb_dev *ndev) +{ + u32 reqid, mtbldata = 0; + unsigned long irqflags; + + /* Enable the ID protection and Completion TLPs translation */ + idt_nt_write(ndev, IDT_NT_NTCTL, IDT_NTCTL_CPEN); + + /* Retrieve the current Requester ID (Bus:Device:Function) */ + reqid = idt_nt_read(ndev, IDT_NT_REQIDCAP); + + /* + * Set the corresponding NT Mapping table entry of port partition index + * with the data to perform the Request ID translation + */ + mtbldata = SET_FIELD(NTMTBLDATA_REQID, 0, reqid) | + SET_FIELD(NTMTBLDATA_PART, 0, ndev->part) | + IDT_NTMTBLDATA_VALID; + spin_lock_irqsave(&ndev->mtbl_lock, irqflags); + idt_nt_write(ndev, IDT_NT_NTMTBLADDR, ndev->part); + idt_nt_write(ndev, IDT_NT_NTMTBLDATA, mtbldata); + spin_unlock_irqrestore(&ndev->mtbl_lock, irqflags); + + /* Notify the peers by setting and clearing the global signal bit */ + idt_nt_write(ndev, IDT_NT_NTGSIGNAL, IDT_NTGSIGNAL_SET); + idt_sw_write(ndev, IDT_SW_SEGSIGSTS, (u32)1 << ndev->part); +} + +/* + * idt_ntb_local_link_disable() - disable the local NTB link. + * @ndev: IDT NTB hardware driver descriptor + * + * In order to enable the NTB link we need: + * - disable Completion TLPs translation + * - clear corresponding mapping table entry + * - notify peers of NTB link state change + */ +static void idt_ntb_local_link_disable(struct idt_ntb_dev *ndev) +{ + unsigned long irqflags; + + /* Disable Completion TLPs translation */ + idt_nt_write(ndev, IDT_NT_NTCTL, 0); + + /* Clear the corresponding NT Mapping table entry */ + spin_lock_irqsave(&ndev->mtbl_lock, irqflags); + idt_nt_write(ndev, IDT_NT_NTMTBLADDR, ndev->part); + idt_nt_write(ndev, IDT_NT_NTMTBLDATA, 0); + spin_unlock_irqrestore(&ndev->mtbl_lock, irqflags); + + /* Notify the peers by setting and clearing the global signal bit */ + idt_nt_write(ndev, IDT_NT_NTGSIGNAL, IDT_NTGSIGNAL_SET); + idt_sw_write(ndev, IDT_SW_SEGSIGSTS, (u32)1 << ndev->part); +} + +/* + * idt_ntb_local_link_is_up() - test wethter local NTB link is up + * @ndev: IDT NTB hardware driver descriptor + * + * Local link is up under the following conditions: + * - Bus mastering is enabled + * - NTCTL has Completion TLPs translation enabled + * - Mapping table permits Request TLPs translation + * NOTE: We don't need to check PCIe link state since it's obviously + * up while we are able to communicate with IDT PCIe-switch + * + * Return: true if link is up, otherwise false + */ +static bool idt_ntb_local_link_is_up(struct idt_ntb_dev *ndev) +{ + unsigned long irqflags; + u32 data; + + /* Read the local Bus Master Enable status */ + data = idt_nt_read(ndev, IDT_NT_PCICMDSTS); + if (!(data & IDT_PCICMDSTS_BME)) + return false; + + /* Read the local Completion TLPs translation enable status */ + data = idt_nt_read(ndev, IDT_NT_NTCTL); + if (!(data & IDT_NTCTL_CPEN)) + return false; + + /* Read Mapping table entry corresponding to the local partition */ + spin_lock_irqsave(&ndev->mtbl_lock, irqflags); + idt_nt_write(ndev, IDT_NT_NTMTBLADDR, ndev->part); + data = idt_nt_read(ndev, IDT_NT_NTMTBLDATA); + spin_unlock_irqrestore(&ndev->mtbl_lock, irqflags); + + return !!(data & IDT_NTMTBLDATA_VALID); +} + +/* + * idt_ntb_peer_link_is_up() - test whether peer NTB link is up + * @ndev: IDT NTB hardware driver descriptor + * @pidx: Peer port index + * + * Peer link is up under the following conditions: + * - PCIe link is up + * - Bus mastering is enabled + * - NTCTL has Completion TLPs translation enabled + * - Mapping table permits Request TLPs translation + * + * Return: true if link is up, otherwise false + */ +static bool idt_ntb_peer_link_is_up(struct idt_ntb_dev *ndev, int pidx) +{ + unsigned long irqflags; + unsigned char port; + u32 data; + + /* Retrieve the device port number */ + port = ndev->peers[pidx].port; + + /* Check whether PCIe link is up */ + data = idt_sw_read(ndev, portdata_tbl[port].sts); + if (!(data & IDT_SWPORTxSTS_LINKUP)) + return false; + + /* Check whether bus mastering is enabled on the peer port */ + data = idt_sw_read(ndev, portdata_tbl[port].pcicmdsts); + if (!(data & IDT_PCICMDSTS_BME)) + return false; + + /* Check if Completion TLPs translation is enabled on the peer port */ + data = idt_sw_read(ndev, portdata_tbl[port].ntctl); + if (!(data & IDT_NTCTL_CPEN)) + return false; + + /* Read Mapping table entry corresponding to the peer partition */ + spin_lock_irqsave(&ndev->mtbl_lock, irqflags); + idt_nt_write(ndev, IDT_NT_NTMTBLADDR, ndev->peers[pidx].part); + data = idt_nt_read(ndev, IDT_NT_NTMTBLDATA); + spin_unlock_irqrestore(&ndev->mtbl_lock, irqflags); + + return !!(data & IDT_NTMTBLDATA_VALID); +} + +/* + * idt_ntb_link_is_up() - get the current ntb link state (NTB API callback) + * @ntb: NTB device context. + * @speed: OUT - The link speed expressed as PCIe generation number. + * @width: OUT - The link width expressed as the number of PCIe lanes. + * + * Get the bitfield of NTB link states for all peer ports + * + * Return: bitfield of indexed ports link state: bit is set/cleared if the + * link is up/down respectively. + */ +static u64 idt_ntb_link_is_up(struct ntb_dev *ntb, + enum ntb_speed *speed, enum ntb_width *width) +{ + struct idt_ntb_dev *ndev = to_ndev_ntb(ntb); + unsigned char pidx; + u64 status; + u32 data; + + /* Retrieve the local link speed and width */ + if (speed != NULL || width != NULL) { + data = idt_nt_read(ndev, IDT_NT_PCIELCTLSTS); + if (speed != NULL) + *speed = GET_FIELD(PCIELCTLSTS_CLS, data); + if (width != NULL) + *width = GET_FIELD(PCIELCTLSTS_NLW, data); + } + + /* If local NTB link isn't up then all the links are considered down */ + if (!idt_ntb_local_link_is_up(ndev)) + return 0; + + /* Collect all the peer ports link states into the bitfield */ + status = 0; + for (pidx = 0; pidx < ndev->peer_cnt; pidx++) { + if (idt_ntb_peer_link_is_up(ndev, pidx)) + status |= ((u64)1 << pidx); + } + + return status; +} + +/* + * idt_ntb_link_enable() - enable local port ntb link (NTB API callback) + * @ntb: NTB device context. + * @max_speed: The maximum link speed expressed as PCIe generation number. + * @max_width: The maximum link width expressed as the number of PCIe lanes. + * + * Enable just local NTB link. PCIe link parameters are ignored. + * + * Return: always zero. + */ +static int idt_ntb_link_enable(struct ntb_dev *ntb, enum ntb_speed speed, + enum ntb_width width) +{ + struct idt_ntb_dev *ndev = to_ndev_ntb(ntb); + + /* Just enable the local NTB link */ + idt_ntb_local_link_enable(ndev); + + dev_dbg(&ndev->ntb.pdev->dev, "Local NTB link enabled"); + + return 0; +} + +/* + * idt_ntb_link_disable() - disable local port ntb link (NTB API callback) + * @ntb: NTB device context. + * + * Disable just local NTB link. + * + * Return: always zero. + */ +static int idt_ntb_link_disable(struct ntb_dev *ntb) +{ + struct idt_ntb_dev *ndev = to_ndev_ntb(ntb); + + /* Just disable the local NTB link */ + idt_ntb_local_link_disable(ndev); + + dev_dbg(&ndev->ntb.pdev->dev, "Local NTB link disabled"); + + return 0; +} + +/*============================================================================= + * 4. Memory Window operations + * + * IDT PCIe-switches have two types of memory windows: MWs with direct + * address translation and MWs with LUT based translation. The first type of + * MWs is simple map of corresponding BAR address space to a memory space + * of specified target port. So it implemets just ont-to-one mapping. Lookup + * table in its turn can map one BAR address space to up to 24 different + * memory spaces of different ports. + * NT-functions BARs can be turned on to implement either direct or lookup + * table based address translations, so: + * BAR0 - NT configuration registers space/direct address translation + * BAR1 - direct address translation/upper address of BAR0x64 + * BAR2 - direct address translation/Lookup table with either 12 or 24 entries + * BAR3 - direct address translation/upper address of BAR2x64 + * BAR4 - direct address translation/Lookup table with either 12 or 24 entries + * BAR5 - direct address translation/upper address of BAR4x64 + * Additionally BAR2 and BAR4 can't have 24-entries LUT enabled at the same + * time. Since the BARs setup can be rather complicated this driver implements + * a scanning algorithm to have all the possible memory windows configuration + * covered. + * + * NOTE 1 BAR setup must be done before Linux kernel enumerated NT-function + * of any port, so this driver would have memory windows configurations fixed. + * In this way all initializations must be performed either by platform BIOS + * or using EEPROM connected to IDT PCIe-switch master SMBus. + * + * NOTE 2 This driver expects BAR0 mapping NT-function configuration space. + * Easy calculation can give us an upper boundary of 29 possible memory windows + * per each NT-function if all the BARs are of 32bit type. + *============================================================================= + */ + +/* + * idt_get_mw_count() - get memory window count + * @mw_type: Memory window type + * + * Return: number of memory windows with respect to the BAR type + */ +static inline unsigned char idt_get_mw_count(enum idt_mw_type mw_type) +{ + switch (mw_type) { + case IDT_MW_DIR: + return 1; + case IDT_MW_LUT12: + return 12; + case IDT_MW_LUT24: + return 24; + default: + break; + } + + return 0; +} + +/* + * idt_get_mw_name() - get memory window name + * @mw_type: Memory window type + * + * Return: pointer to a string with name + */ +static inline char *idt_get_mw_name(enum idt_mw_type mw_type) +{ + switch (mw_type) { + case IDT_MW_DIR: + return "DIR "; + case IDT_MW_LUT12: + return "LUT12"; + case IDT_MW_LUT24: + return "LUT24"; + default: + break; + } + + return "unknown"; +} + +/* + * idt_scan_mws() - scan memory windows of the port + * @ndev: IDT NTB hardware driver descriptor + * @port: Port to get number of memory windows for + * @mw_cnt: Out - number of memory windows + * + * It walks over BAR setup registers of the specified port and determines + * the memory windows parameters if any activated. + * + * Return: array of memory windows + */ +static struct idt_mw_cfg *idt_scan_mws(struct idt_ntb_dev *ndev, int port, + unsigned char *mw_cnt) +{ + struct idt_mw_cfg mws[IDT_MAX_NR_MWS], *ret_mws; + const struct idt_ntb_bar *bars; + enum idt_mw_type mw_type; + unsigned char widx, bidx, en_cnt; + bool bar_64bit = false; + int aprt_size; + u32 data; + + /* Retrieve the array of the BARs registers */ + bars = portdata_tbl[port].bars; + + /* Scan all the BARs belonging to the port */ + *mw_cnt = 0; + for (bidx = 0; bidx < IDT_BAR_CNT; bidx += 1 + bar_64bit) { + /* Read BARSETUP register value */ + data = idt_sw_read(ndev, bars[bidx].setup); + + /* Skip disabled BARs */ + if (!(data & IDT_BARSETUP_EN)) { + bar_64bit = false; + continue; + } + + /* Skip next BARSETUP if current one has 64bit addressing */ + bar_64bit = IS_FLD_SET(BARSETUP_TYPE, data, 64); + + /* Skip configuration space mapping BARs */ + if (data & IDT_BARSETUP_MODE_CFG) + continue; + + /* Retrieve MW type/entries count and aperture size */ + mw_type = GET_FIELD(BARSETUP_ATRAN, data); + en_cnt = idt_get_mw_count(mw_type); + aprt_size = (u64)1 << GET_FIELD(BARSETUP_SIZE, data); + + /* Save configurations of all available memory windows */ + for (widx = 0; widx < en_cnt; widx++, (*mw_cnt)++) { + /* + * IDT can expose a limited number of MWs, so it's bug + * to have more than the driver expects + */ + if (*mw_cnt >= IDT_MAX_NR_MWS) + return ERR_PTR(-EINVAL); + + /* Save basic MW info */ + mws[*mw_cnt].type = mw_type; + mws[*mw_cnt].bar = bidx; + mws[*mw_cnt].idx = widx; + /* It's always DWORD aligned */ + mws[*mw_cnt].addr_align = IDT_TRANS_ALIGN; + /* DIR and LUT approachs differently configure MWs */ + if (mw_type == IDT_MW_DIR) + mws[*mw_cnt].size_max = aprt_size; + else if (mw_type == IDT_MW_LUT12) + mws[*mw_cnt].size_max = aprt_size / 16; + else + mws[*mw_cnt].size_max = aprt_size / 32; + mws[*mw_cnt].size_align = (mw_type == IDT_MW_DIR) ? + IDT_DIR_SIZE_ALIGN : mws[*mw_cnt].size_max; + } + } + + /* Allocate memory for memory window descriptors */ + ret_mws = devm_kcalloc(&ndev->ntb.pdev->dev, *mw_cnt, sizeof(*ret_mws), + GFP_KERNEL); + if (!ret_mws) + return ERR_PTR(-ENOMEM); + + /* Copy the info of detected memory windows */ + memcpy(ret_mws, mws, (*mw_cnt)*sizeof(*ret_mws)); + + return ret_mws; +} + +/* + * idt_init_mws() - initialize memory windows subsystem + * @ndev: IDT NTB hardware driver descriptor + * + * Scan BAR setup registers of local and peer ports to determine the + * outbound and inbound memory windows parameters + * + * Return: zero on success, otherwise a negative error number + */ +static int idt_init_mws(struct idt_ntb_dev *ndev) +{ + struct idt_ntb_peer *peer; + unsigned char pidx; + + /* Scan memory windows of the local port */ + ndev->mws = idt_scan_mws(ndev, ndev->port, &ndev->mw_cnt); + if (IS_ERR(ndev->mws)) { + dev_err(&ndev->ntb.pdev->dev, + "Failed to scan mws of local port %hhu", ndev->port); + return PTR_ERR(ndev->mws); + } + + /* Scan memory windows of the peer ports */ + for (pidx = 0; pidx < ndev->peer_cnt; pidx++) { + peer = &ndev->peers[pidx]; + peer->mws = idt_scan_mws(ndev, peer->port, &peer->mw_cnt); + if (IS_ERR(peer->mws)) { + dev_err(&ndev->ntb.pdev->dev, + "Failed to scan mws of port %hhu", peer->port); + return PTR_ERR(peer->mws); + } + } + + /* Initialize spin locker of the LUT registers */ + spin_lock_init(&ndev->lut_lock); + + dev_dbg(&ndev->ntb.pdev->dev, "Outbound and inbound MWs initialized"); + + return 0; +} + +/* + * idt_ntb_mw_count() - number of inbound memory windows (NTB API callback) + * @ntb: NTB device context. + * @pidx: Port index of peer device. + * + * The value is returned for the specified peer, so generally speaking it can + * be different for different port depending on the IDT PCIe-switch + * initialization. + * + * Return: the number of memory windows. + */ +static int idt_ntb_mw_count(struct ntb_dev *ntb, int pidx) +{ + struct idt_ntb_dev *ndev = to_ndev_ntb(ntb); + + if (pidx < 0 || ndev->peer_cnt <= pidx) + return -EINVAL; + + return ndev->peers[pidx].mw_cnt; +} + +/* + * idt_ntb_mw_get_align() - inbound memory window parameters (NTB API callback) + * @ntb: NTB device context. + * @pidx: Port index of peer device. + * @widx: Memory window index. + * @addr_align: OUT - the base alignment for translating the memory window + * @size_align: OUT - the size alignment for translating the memory window + * @size_max: OUT - the maximum size of the memory window + * + * The peer memory window parameters have already been determined, so just + * return the corresponding values, which mustn't change within session. + * + * Return: Zero on success, otherwise a negative error number. + */ +static int idt_ntb_mw_get_align(struct ntb_dev *ntb, int pidx, int widx, + resource_size_t *addr_align, + resource_size_t *size_align, + resource_size_t *size_max) +{ + struct idt_ntb_dev *ndev = to_ndev_ntb(ntb); + struct idt_ntb_peer *peer; + + if (pidx < 0 || ndev->peer_cnt <= pidx) + return -EINVAL; + + peer = &ndev->peers[pidx]; + + if (widx < 0 || peer->mw_cnt <= widx) + return -EINVAL; + + if (addr_align != NULL) + *addr_align = peer->mws[widx].addr_align; + + if (size_align != NULL) + *size_align = peer->mws[widx].size_align; + + if (size_max != NULL) + *size_max = peer->mws[widx].size_max; + + return 0; +} + +/* + * idt_ntb_peer_mw_count() - number of outbound memory windows + * (NTB API callback) + * @ntb: NTB device context. + * + * Outbound memory windows parameters have been determined based on the + * BAR setup registers value, which are mostly constants within one session. + * + * Return: the number of memory windows. + */ +static int idt_ntb_peer_mw_count(struct ntb_dev *ntb) +{ + struct idt_ntb_dev *ndev = to_ndev_ntb(ntb); + + return ndev->mw_cnt; +} + +/* + * idt_ntb_peer_mw_get_addr() - get map address of an outbound memory window + * (NTB API callback) + * @ntb: NTB device context. + * @widx: Memory window index (within ntb_peer_mw_count() return value). + * @base: OUT - the base address of mapping region. + * @size: OUT - the size of mapping region. + * + * Return just parameters of BAR resources mapping. Size reflects just the size + * of the resource + * + * Return: Zero on success, otherwise a negative error number. + */ +static int idt_ntb_peer_mw_get_addr(struct ntb_dev *ntb, int widx, + phys_addr_t *base, resource_size_t *size) +{ + struct idt_ntb_dev *ndev = to_ndev_ntb(ntb); + + if (widx < 0 || ndev->mw_cnt <= widx) + return -EINVAL; + + /* Mapping address is just properly shifted BAR resource start */ + if (base != NULL) + *base = pci_resource_start(ntb->pdev, ndev->mws[widx].bar) + + ndev->mws[widx].idx * ndev->mws[widx].size_max; + + /* Mapping size has already been calculated at MWs scanning */ + if (size != NULL) + *size = ndev->mws[widx].size_max; + + return 0; +} + +/* + * idt_ntb_peer_mw_set_trans() - set a translation address of a memory window + * (NTB API callback) + * @ntb: NTB device context. + * @pidx: Port index of peer device the translation address received from. + * @widx: Memory window index. + * @addr: The dma address of the shared memory to access. + * @size: The size of the shared memory to access. + * + * The Direct address translation and LUT base translation is initialized a + * bit differenet. Although the parameters restriction are now determined by + * the same code. + * + * Return: Zero on success, otherwise an error number. + */ +static int idt_ntb_peer_mw_set_trans(struct ntb_dev *ntb, int pidx, int widx, + u64 addr, resource_size_t size) +{ + struct idt_ntb_dev *ndev = to_ndev_ntb(ntb); + struct idt_mw_cfg *mw_cfg; + u32 data = 0, lutoff = 0; + + if (pidx < 0 || ndev->peer_cnt <= pidx) + return -EINVAL; + + if (widx < 0 || ndev->mw_cnt <= widx) + return -EINVAL; + + /* + * Retrieve the memory window config to make sure the passed arguments + * fit it restrictions + */ + mw_cfg = &ndev->mws[widx]; + if (!IS_ALIGNED(addr, mw_cfg->addr_align)) + return -EINVAL; + if (!IS_ALIGNED(size, mw_cfg->size_align) || size > mw_cfg->size_max) + return -EINVAL; + + /* DIR and LUT based translations are initialized differently */ + if (mw_cfg->type == IDT_MW_DIR) { + const struct idt_ntb_bar *bar = &ntdata_tbl.bars[mw_cfg->bar]; + u64 limit; + /* Set destination partition of translation */ + data = idt_nt_read(ndev, bar->setup); + data = SET_FIELD(BARSETUP_TPART, data, ndev->peers[pidx].part); + idt_nt_write(ndev, bar->setup, data); + /* Set translation base address */ + idt_nt_write(ndev, bar->ltbase, (u32)addr); + idt_nt_write(ndev, bar->utbase, (u32)(addr >> 32)); + /* Set the custom BAR aperture limit */ + limit = pci_bus_address(ntb->pdev, mw_cfg->bar) + size; + idt_nt_write(ndev, bar->limit, (u32)limit); + if (IS_FLD_SET(BARSETUP_TYPE, data, 64)) + idt_nt_write(ndev, (bar + 1)->limit, (limit >> 32)); + } else { + unsigned long irqflags; + /* Initialize corresponding LUT entry */ + lutoff = SET_FIELD(LUTOFFSET_INDEX, 0, mw_cfg->idx) | + SET_FIELD(LUTOFFSET_BAR, 0, mw_cfg->bar); + data = SET_FIELD(LUTUDATA_PART, 0, ndev->peers[pidx].part) | + IDT_LUTUDATA_VALID; + spin_lock_irqsave(&ndev->lut_lock, irqflags); + idt_nt_write(ndev, IDT_NT_LUTOFFSET, lutoff); + idt_nt_write(ndev, IDT_NT_LUTLDATA, (u32)addr); + idt_nt_write(ndev, IDT_NT_LUTMDATA, (u32)(addr >> 32)); + idt_nt_write(ndev, IDT_NT_LUTUDATA, data); + spin_unlock_irqrestore(&ndev->lut_lock, irqflags); + /* Limit address isn't specified since size is fixed for LUT */ + } + + return 0; +} + +/* + * idt_ntb_peer_mw_clear_trans() - clear the outbound MW translation address + * (NTB API callback) + * @ntb: NTB device context. + * @pidx: Port index of peer device. + * @widx: Memory window index. + * + * It effectively disables the translation over the specified outbound MW. + * + * Return: Zero on success, otherwise an error number. + */ +static int idt_ntb_peer_mw_clear_trans(struct ntb_dev *ntb, int pidx, + int widx) +{ + struct idt_ntb_dev *ndev = to_ndev_ntb(ntb); + struct idt_mw_cfg *mw_cfg; + + if (pidx < 0 || ndev->peer_cnt <= pidx) + return -EINVAL; + + if (widx < 0 || ndev->mw_cnt <= widx) + return -EINVAL; + + mw_cfg = &ndev->mws[widx]; + + /* DIR and LUT based translations are initialized differently */ + if (mw_cfg->type == IDT_MW_DIR) { + const struct idt_ntb_bar *bar = &ntdata_tbl.bars[mw_cfg->bar]; + u32 data; + /* Read BARSETUP to check BAR type */ + data = idt_nt_read(ndev, bar->setup); + /* Disable translation by specifying zero BAR limit */ + idt_nt_write(ndev, bar->limit, 0); + if (IS_FLD_SET(BARSETUP_TYPE, data, 64)) + idt_nt_write(ndev, (bar + 1)->limit, 0); + } else { + unsigned long irqflags; + u32 lutoff; + /* Clear the corresponding LUT entry up */ + lutoff = SET_FIELD(LUTOFFSET_INDEX, 0, mw_cfg->idx) | + SET_FIELD(LUTOFFSET_BAR, 0, mw_cfg->bar); + spin_lock_irqsave(&ndev->lut_lock, irqflags); + idt_nt_write(ndev, IDT_NT_LUTOFFSET, lutoff); + idt_nt_write(ndev, IDT_NT_LUTLDATA, 0); + idt_nt_write(ndev, IDT_NT_LUTMDATA, 0); + idt_nt_write(ndev, IDT_NT_LUTUDATA, 0); + spin_unlock_irqrestore(&ndev->lut_lock, irqflags); + } + + return 0; +} + +/*============================================================================= + * 5. Doorbell operations + * + * Doorbell functionality of IDT PCIe-switches is pretty unusual. First of + * all there is global doorbell register which state can be changed by any + * NT-function of the IDT device in accordance with global permissions. These + * permissions configs are not supported by NTB API, so it must be done by + * either BIOS or EEPROM settings. In the same way the state of the global + * doorbell is reflected to the NT-functions local inbound doorbell registers. + * It can lead to situations when client driver sets some peer doorbell bits + * and get them bounced back to local inbound doorbell if permissions are + * granted. + * Secondly there is just one IRQ vector for Doorbell, Message, Temperature + * and Switch events, so if client driver left any of Doorbell bits set and + * some other event occurred, the driver will be notified of Doorbell event + * again. + *============================================================================= + */ + +/* + * idt_db_isr() - doorbell event ISR + * @ndev: IDT NTB hardware driver descriptor + * @ntint_sts: NT-function interrupt status + * + * Doorbell event happans when DBELL bit of NTINTSTS switches from 0 to 1. + * It happens only when unmasked doorbell bits are set to ones on completely + * zeroed doorbell register. + * The method is called from PCIe ISR bottom-half routine. + */ +static void idt_db_isr(struct idt_ntb_dev *ndev, u32 ntint_sts) +{ + /* + * Doorbell IRQ status will be cleaned only when client + * driver unsets all the doorbell bits. + */ + dev_dbg(&ndev->ntb.pdev->dev, "DB IRQ detected %#08x", ntint_sts); + + /* Notify the client driver of possible doorbell state change */ + ntb_db_event(&ndev->ntb, 0); +} + +/* + * idt_ntb_db_valid_mask() - get a mask of doorbell bits supported by the ntb + * (NTB API callback) + * @ntb: NTB device context. + * + * IDT PCIe-switches expose just one Doorbell register of DWORD size. + * + * Return: A mask of doorbell bits supported by the ntb. + */ +static u64 idt_ntb_db_valid_mask(struct ntb_dev *ntb) +{ + return IDT_DBELL_MASK; +} + +/* + * idt_ntb_db_read() - read the local doorbell register (NTB API callback) + * @ntb: NTB device context. + * + * There is just on inbound doorbell register of each NT-function, so + * this method return it value. + * + * Return: The bits currently set in the local doorbell register. + */ +static u64 idt_ntb_db_read(struct ntb_dev *ntb) +{ + struct idt_ntb_dev *ndev = to_ndev_ntb(ntb); + + return idt_nt_read(ndev, IDT_NT_INDBELLSTS); +} + +/* + * idt_ntb_db_clear() - clear bits in the local doorbell register + * (NTB API callback) + * @ntb: NTB device context. + * @db_bits: Doorbell bits to clear. + * + * Clear bits of inbound doorbell register by writing ones to it. + * + * NOTE! Invalid bits are always considered cleared so it's not an error + * to clear them over. + * + * Return: always zero as success. + */ +static int idt_ntb_db_clear(struct ntb_dev *ntb, u64 db_bits) +{ + struct idt_ntb_dev *ndev = to_ndev_ntb(ntb); + + idt_nt_write(ndev, IDT_NT_INDBELLSTS, (u32)db_bits); + + return 0; +} + +/* + * idt_ntb_db_read_mask() - read the local doorbell mask (NTB API callback) + * @ntb: NTB device context. + * + * Each inbound doorbell bit can be masked from generating IRQ by setting + * the corresponding bit in inbound doorbell mask. So this method returns + * the value of the register. + * + * Return: The bits currently set in the local doorbell mask register. + */ +static u64 idt_ntb_db_read_mask(struct ntb_dev *ntb) +{ + struct idt_ntb_dev *ndev = to_ndev_ntb(ntb); + + return idt_nt_read(ndev, IDT_NT_INDBELLMSK); +} + +/* + * idt_ntb_db_set_mask() - set bits in the local doorbell mask + * (NTB API callback) + * @ntb: NTB device context. + * @db_bits: Doorbell mask bits to set. + * + * The inbound doorbell register mask value must be read, then OR'ed with + * passed field and only then set back. + * + * Return: zero on success, negative error if invalid argument passed. + */ +static int idt_ntb_db_set_mask(struct ntb_dev *ntb, u64 db_bits) +{ + struct idt_ntb_dev *ndev = to_ndev_ntb(ntb); + + return idt_reg_set_bits(ndev, IDT_NT_INDBELLMSK, &ndev->db_mask_lock, + IDT_DBELL_MASK, db_bits); +} + +/* + * idt_ntb_db_clear_mask() - clear bits in the local doorbell mask + * (NTB API callback) + * @ntb: NTB device context. + * @db_bits: Doorbell bits to clear. + * + * The method just clears the set bits up in accordance with the passed + * bitfield. IDT PCIe-switch shall generate an interrupt if there hasn't + * been any unmasked bit set before current unmasking. Otherwise IRQ won't + * be generated since there is only one IRQ vector for all doorbells. + * + * Return: always zero as success + */ +static int idt_ntb_db_clear_mask(struct ntb_dev *ntb, u64 db_bits) +{ + struct idt_ntb_dev *ndev = to_ndev_ntb(ntb); + + idt_reg_clear_bits(ndev, IDT_NT_INDBELLMSK, &ndev->db_mask_lock, + db_bits); + + return 0; +} + +/* + * idt_ntb_peer_db_set() - set bits in the peer doorbell register + * (NTB API callback) + * @ntb: NTB device context. + * @db_bits: Doorbell bits to set. + * + * IDT PCIe-switches exposes local outbound doorbell register to change peer + * inbound doorbell register state. + * + * Return: zero on success, negative error if invalid argument passed. + */ +static int idt_ntb_peer_db_set(struct ntb_dev *ntb, u64 db_bits) +{ + struct idt_ntb_dev *ndev = to_ndev_ntb(ntb); + + if (db_bits & ~(u64)IDT_DBELL_MASK) + return -EINVAL; + + idt_nt_write(ndev, IDT_NT_OUTDBELLSET, (u32)db_bits); + return 0; +} + +/*============================================================================= + * 6. Messaging operations + * + * Each NT-function of IDT PCIe-switch has four inbound and four outbound + * message registers. Each outbound message register can be connected to one or + * even more than one peer inbound message registers by setting global + * configurations. Since NTB API permits one-on-one message registers mapping + * only, the driver acts in according with that restriction. + *============================================================================= + */ + +/* + * idt_init_msg() - initialize messaging interface + * @ndev: IDT NTB hardware driver descriptor + * + * Just initialize the message registers routing tables locker. + */ +static void idt_init_msg(struct idt_ntb_dev *ndev) +{ + unsigned char midx; + + /* Init the messages routing table lockers */ + for (midx = 0; midx < IDT_MSG_CNT; midx++) + spin_lock_init(&ndev->msg_locks[midx]); + + dev_dbg(&ndev->ntb.pdev->dev, "NTB Messaging initialized"); +} + +/* + * idt_msg_isr() - message event ISR + * @ndev: IDT NTB hardware driver descriptor + * @ntint_sts: NT-function interrupt status + * + * Message event happens when MSG bit of NTINTSTS switches from 0 to 1. + * It happens only when unmasked message status bits are set to ones on + * completely zeroed message status register. + * The method is called from PCIe ISR bottom-half routine. + */ +static void idt_msg_isr(struct idt_ntb_dev *ndev, u32 ntint_sts) +{ + /* + * Message IRQ status will be cleaned only when client + * driver unsets all the message status bits. + */ + dev_dbg(&ndev->ntb.pdev->dev, "Message IRQ detected %#08x", ntint_sts); + + /* Notify the client driver of possible message status change */ + ntb_msg_event(&ndev->ntb); +} + +/* + * idt_ntb_msg_count() - get the number of message registers (NTB API callback) + * @ntb: NTB device context. + * + * IDT PCIe-switches support four message registers. + * + * Return: the number of message registers. + */ +static int idt_ntb_msg_count(struct ntb_dev *ntb) +{ + return IDT_MSG_CNT; +} + +/* + * idt_ntb_msg_inbits() - get a bitfield of inbound message registers status + * (NTB API callback) + * @ntb: NTB device context. + * + * NT message status register is shared between inbound and outbound message + * registers status + * + * Return: bitfield of inbound message registers. + */ +static u64 idt_ntb_msg_inbits(struct ntb_dev *ntb) +{ + return (u64)IDT_INMSG_MASK; +} + +/* + * idt_ntb_msg_outbits() - get a bitfield of outbound message registers status + * (NTB API callback) + * @ntb: NTB device context. + * + * NT message status register is shared between inbound and outbound message + * registers status + * + * Return: bitfield of outbound message registers. + */ +static u64 idt_ntb_msg_outbits(struct ntb_dev *ntb) +{ + return (u64)IDT_OUTMSG_MASK; +} + +/* + * idt_ntb_msg_read_sts() - read the message registers status (NTB API callback) + * @ntb: NTB device context. + * + * IDT PCIe-switches expose message status registers to notify drivers of + * incoming data and failures in case if peer message register isn't freed. + * + * Return: status bits of message registers + */ +static u64 idt_ntb_msg_read_sts(struct ntb_dev *ntb) +{ + struct idt_ntb_dev *ndev = to_ndev_ntb(ntb); + + return idt_nt_read(ndev, IDT_NT_MSGSTS); +} + +/* + * idt_ntb_msg_clear_sts() - clear status bits of message registers + * (NTB API callback) + * @ntb: NTB device context. + * @sts_bits: Status bits to clear. + * + * Clear bits in the status register by writing ones. + * + * NOTE! Invalid bits are always considered cleared so it's not an error + * to clear them over. + * + * Return: always zero as success. + */ +static int idt_ntb_msg_clear_sts(struct ntb_dev *ntb, u64 sts_bits) +{ + struct idt_ntb_dev *ndev = to_ndev_ntb(ntb); + + idt_nt_write(ndev, IDT_NT_MSGSTS, sts_bits); + + return 0; +} + +/* + * idt_ntb_msg_set_mask() - set mask of message register status bits + * (NTB API callback) + * @ntb: NTB device context. + * @mask_bits: Mask bits. + * + * Mask the message status bits from raising an IRQ. + * + * Return: zero on success, negative error if invalid argument passed. + */ +static int idt_ntb_msg_set_mask(struct ntb_dev *ntb, u64 mask_bits) +{ + struct idt_ntb_dev *ndev = to_ndev_ntb(ntb); + + return idt_reg_set_bits(ndev, IDT_NT_MSGSTSMSK, &ndev->msg_mask_lock, + IDT_MSG_MASK, mask_bits); +} + +/* + * idt_ntb_msg_clear_mask() - clear message registers mask + * (NTB API callback) + * @ntb: NTB device context. + * @mask_bits: Mask bits. + * + * Clear mask of message status bits IRQs. + * + * Return: always zero as success. + */ +static int idt_ntb_msg_clear_mask(struct ntb_dev *ntb, u64 mask_bits) +{ + struct idt_ntb_dev *ndev = to_ndev_ntb(ntb); + + idt_reg_clear_bits(ndev, IDT_NT_MSGSTSMSK, &ndev->msg_mask_lock, + mask_bits); + + return 0; +} + +/* + * idt_ntb_msg_read() - read message register with specified index + * (NTB API callback) + * @ntb: NTB device context. + * @pidx: OUT - Port index of peer device a message retrieved from + * @midx: Message register index + * + * Read data from the specified message register and source register. + * + * Return: inbound message register value. + */ +static u32 idt_ntb_msg_read(struct ntb_dev *ntb, int *pidx, int midx) +{ + struct idt_ntb_dev *ndev = to_ndev_ntb(ntb); + + if (midx < 0 || IDT_MSG_CNT <= midx) + return ~(u32)0; + + /* Retrieve source port index of the message */ + if (pidx != NULL) { + u32 srcpart; + + srcpart = idt_nt_read(ndev, ntdata_tbl.msgs[midx].src); + *pidx = ndev->part_idx_map[srcpart]; + + /* Sanity check partition index (for initial case) */ + if (*pidx == -EINVAL) + *pidx = 0; + } + + /* Retrieve data of the corresponding message register */ + return idt_nt_read(ndev, ntdata_tbl.msgs[midx].in); +} + +/* + * idt_ntb_peer_msg_write() - write data to the specified message register + * (NTB API callback) + * @ntb: NTB device context. + * @pidx: Port index of peer device a message being sent to + * @midx: Message register index + * @msg: Data to send + * + * Just try to send data to a peer. Message status register should be + * checked by client driver. + * + * Return: zero on success, negative error if invalid argument passed. + */ +static int idt_ntb_peer_msg_write(struct ntb_dev *ntb, int pidx, int midx, + u32 msg) +{ + struct idt_ntb_dev *ndev = to_ndev_ntb(ntb); + unsigned long irqflags; + u32 swpmsgctl = 0; + + if (midx < 0 || IDT_MSG_CNT <= midx) + return -EINVAL; + + if (pidx < 0 || ndev->peer_cnt <= pidx) + return -EINVAL; + + /* Collect the routing information */ + swpmsgctl = SET_FIELD(SWPxMSGCTL_REG, 0, midx) | + SET_FIELD(SWPxMSGCTL_PART, 0, ndev->peers[pidx].part); + + /* Lock the messages routing table of the specified register */ + spin_lock_irqsave(&ndev->msg_locks[midx], irqflags); + /* Set the route and send the data */ + idt_sw_write(ndev, partdata_tbl[ndev->part].msgctl[midx], swpmsgctl); + idt_nt_write(ndev, ntdata_tbl.msgs[midx].out, msg); + /* Unlock the messages routing table */ + spin_unlock_irqrestore(&ndev->msg_locks[midx], irqflags); + + /* Client driver shall check the status register */ + return 0; +} + +/*============================================================================= + * 7. Temperature sensor operations + * + * IDT PCIe-switch has an embedded temperature sensor, which can be used to + * check current chip core temperature. Since a workload environment can be + * different on different platforms, an offset and ADC/filter settings can be + * specified. Although the offset configuration is only exposed to the sysfs + * hwmon interface at the moment. The rest of the settings can be adjusted + * for instance by the BIOS/EEPROM firmware. + *============================================================================= + */ + +/* + * idt_get_deg() - convert millidegree Celsius value to just degree + * @mdegC: IN - millidegree Celsius value + * + * Return: Degree corresponding to the passed millidegree value + */ +static inline s8 idt_get_deg(long mdegC) +{ + return mdegC / 1000; +} + +/* + * idt_get_frac() - retrieve 0/0.5 fraction of the millidegree Celsius value + * @mdegC: IN - millidegree Celsius value + * + * Return: 0/0.5 degree fraction of the passed millidegree value + */ +static inline u8 idt_get_deg_frac(long mdegC) +{ + return (mdegC % 1000) >= 500 ? 5 : 0; +} + +/* + * idt_get_temp_fmt() - convert millidegree Celsius value to 0:7:1 format + * @mdegC: IN - millidegree Celsius value + * + * Return: 0:7:1 format acceptable by the IDT temperature sensor + */ +static inline u8 idt_temp_get_fmt(long mdegC) +{ + return (idt_get_deg(mdegC) << 1) | (idt_get_deg_frac(mdegC) ? 1 : 0); +} + +/* + * idt_get_temp_sval() - convert temp sample to signed millidegree Celsius + * @data: IN - shifted to LSB 8-bits temperature sample + * + * Return: signed millidegree Celsius + */ +static inline long idt_get_temp_sval(u32 data) +{ + return ((s8)data / 2) * 1000 + (data & 0x1 ? 500 : 0); +} + +/* + * idt_get_temp_sval() - convert temp sample to unsigned millidegree Celsius + * @data: IN - shifted to LSB 8-bits temperature sample + * + * Return: unsigned millidegree Celsius + */ +static inline long idt_get_temp_uval(u32 data) +{ + return (data / 2) * 1000 + (data & 0x1 ? 500 : 0); +} + +/* + * idt_read_temp() - read temperature from chip sensor + * @ntb: NTB device context. + * @type: IN - type of the temperature value to read + * @val: OUT - integer value of temperature in millidegree Celsius + */ +static void idt_read_temp(struct idt_ntb_dev *ndev, + const enum idt_temp_val type, long *val) +{ + u32 data; + + /* Alter the temperature field in accordance with the passed type */ + switch (type) { + case IDT_TEMP_CUR: + data = GET_FIELD(TMPSTS_TEMP, + idt_sw_read(ndev, IDT_SW_TMPSTS)); + break; + case IDT_TEMP_LOW: + data = GET_FIELD(TMPSTS_LTEMP, + idt_sw_read(ndev, IDT_SW_TMPSTS)); + break; + case IDT_TEMP_HIGH: + data = GET_FIELD(TMPSTS_HTEMP, + idt_sw_read(ndev, IDT_SW_TMPSTS)); + break; + case IDT_TEMP_OFFSET: + /* This is the only field with signed 0:7:1 format */ + data = GET_FIELD(TMPADJ_OFFSET, + idt_sw_read(ndev, IDT_SW_TMPADJ)); + *val = idt_get_temp_sval(data); + return; + default: + data = GET_FIELD(TMPSTS_TEMP, + idt_sw_read(ndev, IDT_SW_TMPSTS)); + break; + } + + /* The rest of the fields accept unsigned 0:7:1 format */ + *val = idt_get_temp_uval(data); +} + +/* + * idt_write_temp() - write temperature to the chip sensor register + * @ntb: NTB device context. + * @type: IN - type of the temperature value to change + * @val: IN - integer value of temperature in millidegree Celsius + */ +static void idt_write_temp(struct idt_ntb_dev *ndev, + const enum idt_temp_val type, const long val) +{ + unsigned int reg; + u32 data; + u8 fmt; + + /* Retrieve the properly formatted temperature value */ + fmt = idt_temp_get_fmt(val); + + mutex_lock(&ndev->hwmon_mtx); + switch (type) { + case IDT_TEMP_LOW: + reg = IDT_SW_TMPALARM; + data = SET_FIELD(TMPALARM_LTEMP, idt_sw_read(ndev, reg), fmt) & + ~IDT_TMPALARM_IRQ_MASK; + break; + case IDT_TEMP_HIGH: + reg = IDT_SW_TMPALARM; + data = SET_FIELD(TMPALARM_HTEMP, idt_sw_read(ndev, reg), fmt) & + ~IDT_TMPALARM_IRQ_MASK; + break; + case IDT_TEMP_OFFSET: + reg = IDT_SW_TMPADJ; + data = SET_FIELD(TMPADJ_OFFSET, idt_sw_read(ndev, reg), fmt); + break; + default: + goto inval_spin_unlock; + } + + idt_sw_write(ndev, reg, data); + +inval_spin_unlock: + mutex_unlock(&ndev->hwmon_mtx); +} + +/* + * idt_sysfs_show_temp() - printout corresponding temperature value + * @dev: Pointer to the NTB device structure + * @da: Sensor device attribute structure + * @buf: Buffer to print temperature out + * + * Return: Number of written symbols or negative error + */ +static ssize_t idt_sysfs_show_temp(struct device *dev, + struct device_attribute *da, char *buf) +{ + struct sensor_device_attribute *attr = to_sensor_dev_attr(da); + struct idt_ntb_dev *ndev = dev_get_drvdata(dev); + enum idt_temp_val type = attr->index; + long mdeg; + + idt_read_temp(ndev, type, &mdeg); + return sprintf(buf, "%ld\n", mdeg); +} + +/* + * idt_sysfs_set_temp() - set corresponding temperature value + * @dev: Pointer to the NTB device structure + * @da: Sensor device attribute structure + * @buf: Buffer to print temperature out + * @count: Size of the passed buffer + * + * Return: Number of written symbols or negative error + */ +static ssize_t idt_sysfs_set_temp(struct device *dev, + struct device_attribute *da, const char *buf, + size_t count) +{ + struct sensor_device_attribute *attr = to_sensor_dev_attr(da); + struct idt_ntb_dev *ndev = dev_get_drvdata(dev); + enum idt_temp_val type = attr->index; + long mdeg; + int ret; + + ret = kstrtol(buf, 10, &mdeg); + if (ret) + return ret; + + /* Clamp the passed value in accordance with the type */ + if (type == IDT_TEMP_OFFSET) + mdeg = clamp_val(mdeg, IDT_TEMP_MIN_OFFSET, + IDT_TEMP_MAX_OFFSET); + else + mdeg = clamp_val(mdeg, IDT_TEMP_MIN_MDEG, IDT_TEMP_MAX_MDEG); + + idt_write_temp(ndev, type, mdeg); + + return count; +} + +/* + * idt_sysfs_reset_hist() - reset temperature history + * @dev: Pointer to the NTB device structure + * @da: Sensor device attribute structure + * @buf: Buffer to print temperature out + * @count: Size of the passed buffer + * + * Return: Number of written symbols or negative error + */ +static ssize_t idt_sysfs_reset_hist(struct device *dev, + struct device_attribute *da, + const char *buf, size_t count) +{ + struct idt_ntb_dev *ndev = dev_get_drvdata(dev); + + /* Just set the maximal value to the lowest temperature field and + * minimal value to the highest temperature field + */ + idt_write_temp(ndev, IDT_TEMP_LOW, IDT_TEMP_MAX_MDEG); + idt_write_temp(ndev, IDT_TEMP_HIGH, IDT_TEMP_MIN_MDEG); + + return count; +} + +/* + * Hwmon IDT sysfs attributes + */ +static SENSOR_DEVICE_ATTR(temp1_input, 0444, idt_sysfs_show_temp, NULL, + IDT_TEMP_CUR); +static SENSOR_DEVICE_ATTR(temp1_lowest, 0444, idt_sysfs_show_temp, NULL, + IDT_TEMP_LOW); +static SENSOR_DEVICE_ATTR(temp1_highest, 0444, idt_sysfs_show_temp, NULL, + IDT_TEMP_HIGH); +static SENSOR_DEVICE_ATTR(temp1_offset, 0644, idt_sysfs_show_temp, + idt_sysfs_set_temp, IDT_TEMP_OFFSET); +static DEVICE_ATTR(temp1_reset_history, 0200, NULL, idt_sysfs_reset_hist); + +/* + * Hwmon IDT sysfs attributes group + */ +static struct attribute *idt_temp_attrs[] = { + &sensor_dev_attr_temp1_input.dev_attr.attr, + &sensor_dev_attr_temp1_lowest.dev_attr.attr, + &sensor_dev_attr_temp1_highest.dev_attr.attr, + &sensor_dev_attr_temp1_offset.dev_attr.attr, + &dev_attr_temp1_reset_history.attr, + NULL +}; +ATTRIBUTE_GROUPS(idt_temp); + +/* + * idt_init_temp() - initialize temperature sensor interface + * @ndev: IDT NTB hardware driver descriptor + * + * Simple sensor initializarion method is responsible for device switching + * on and resource management based hwmon interface registration. Note, that + * since the device is shared we won't disable it on remove, but leave it + * working until the system is powered off. + */ +static void idt_init_temp(struct idt_ntb_dev *ndev) +{ + struct device *hwmon; + + /* Enable sensor if it hasn't been already */ + idt_sw_write(ndev, IDT_SW_TMPCTL, 0x0); + + /* Initialize hwmon interface fields */ + mutex_init(&ndev->hwmon_mtx); + + hwmon = devm_hwmon_device_register_with_groups(&ndev->ntb.pdev->dev, + ndev->swcfg->name, ndev, idt_temp_groups); + if (IS_ERR(hwmon)) { + dev_err(&ndev->ntb.pdev->dev, "Couldn't create hwmon device"); + return; + } + + dev_dbg(&ndev->ntb.pdev->dev, "Temperature HWmon interface registered"); +} + +/*============================================================================= + * 8. ISRs related operations + * + * IDT PCIe-switch has strangely developed IRQ system. There is just one + * interrupt vector for doorbell and message registers. So the hardware driver + * can't determine actual source of IRQ if, for example, message event happened + * while any of unmasked doorbell is still set. The similar situation may be if + * switch or temperature sensor events pop up. The difference is that SEVENT + * and TMPSENSOR bits of NT interrupt status register can be cleaned by + * IRQ handler so a next interrupt request won't have false handling of + * corresponding events. + * The hardware driver has only bottom-half handler of the IRQ, since if any + * of events happened the device won't raise it again before the last one is + * handled by clearing of corresponding NTINTSTS bit. + *============================================================================= + */ + +static irqreturn_t idt_thread_isr(int irq, void *devid); + +/* + * idt_init_isr() - initialize PCIe interrupt handler + * @ndev: IDT NTB hardware driver descriptor + * + * Return: zero on success, otherwise a negative error number. + */ +static int idt_init_isr(struct idt_ntb_dev *ndev) +{ + struct pci_dev *pdev = ndev->ntb.pdev; + u32 ntint_mask; + int ret; + + /* Allocate just one interrupt vector for the ISR */ + ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_MSI | PCI_IRQ_LEGACY); + if (ret != 1) { + dev_err(&pdev->dev, "Failed to allocate IRQ vector"); + return ret; + } + + /* Retrieve the IRQ vector */ + ret = pci_irq_vector(pdev, 0); + if (ret < 0) { + dev_err(&pdev->dev, "Failed to get IRQ vector"); + goto err_free_vectors; + } + + /* Set the IRQ handler */ + ret = devm_request_threaded_irq(&pdev->dev, ret, NULL, idt_thread_isr, + IRQF_ONESHOT, NTB_IRQNAME, ndev); + if (ret != 0) { + dev_err(&pdev->dev, "Failed to set MSI IRQ handler, %d", ret); + goto err_free_vectors; + } + + /* Unmask Message/Doorbell/SE interrupts */ + ntint_mask = idt_nt_read(ndev, IDT_NT_NTINTMSK) & ~IDT_NTINTMSK_ALL; + idt_nt_write(ndev, IDT_NT_NTINTMSK, ntint_mask); + + /* From now on the interrupts are enabled */ + dev_dbg(&pdev->dev, "NTB interrupts initialized"); + + return 0; + +err_free_vectors: + pci_free_irq_vectors(pdev); + + return ret; +} + +/* + * idt_deinit_ist() - deinitialize PCIe interrupt handler + * @ndev: IDT NTB hardware driver descriptor + * + * Disable corresponding interrupts and free allocated IRQ vectors. + */ +static void idt_deinit_isr(struct idt_ntb_dev *ndev) +{ + struct pci_dev *pdev = ndev->ntb.pdev; + u32 ntint_mask; + + /* Mask interrupts back */ + ntint_mask = idt_nt_read(ndev, IDT_NT_NTINTMSK) | IDT_NTINTMSK_ALL; + idt_nt_write(ndev, IDT_NT_NTINTMSK, ntint_mask); + + /* Manually free IRQ otherwise PCI free irq vectors will fail */ + devm_free_irq(&pdev->dev, pci_irq_vector(pdev, 0), ndev); + + /* Free allocated IRQ vectors */ + pci_free_irq_vectors(pdev); + + dev_dbg(&pdev->dev, "NTB interrupts deinitialized"); +} + +/* + * idt_thread_isr() - NT function interrupts handler + * @irq: IRQ number + * @devid: Custom buffer + * + * It reads current NT interrupts state register and handles all the event + * it declares. + * The method is bottom-half routine of actual default PCIe IRQ handler. + */ +static irqreturn_t idt_thread_isr(int irq, void *devid) +{ + struct idt_ntb_dev *ndev = devid; + bool handled = false; + u32 ntint_sts; + + /* Read the NT interrupts status register */ + ntint_sts = idt_nt_read(ndev, IDT_NT_NTINTSTS); + + /* Handle messaging interrupts */ + if (ntint_sts & IDT_NTINTSTS_MSG) { + idt_msg_isr(ndev, ntint_sts); + handled = true; + } + + /* Handle doorbell interrupts */ + if (ntint_sts & IDT_NTINTSTS_DBELL) { + idt_db_isr(ndev, ntint_sts); + handled = true; + } + + /* Handle switch event interrupts */ + if (ntint_sts & IDT_NTINTSTS_SEVENT) { + idt_se_isr(ndev, ntint_sts); + handled = true; + } + + dev_dbg(&ndev->ntb.pdev->dev, "IDT IRQs 0x%08x handled", ntint_sts); + + return handled ? IRQ_HANDLED : IRQ_NONE; +} + +/*=========================================================================== + * 9. NTB hardware driver initialization + *=========================================================================== + */ + +/* + * NTB API operations + */ +static const struct ntb_dev_ops idt_ntb_ops = { + .port_number = idt_ntb_port_number, + .peer_port_count = idt_ntb_peer_port_count, + .peer_port_number = idt_ntb_peer_port_number, + .peer_port_idx = idt_ntb_peer_port_idx, + .link_is_up = idt_ntb_link_is_up, + .link_enable = idt_ntb_link_enable, + .link_disable = idt_ntb_link_disable, + .mw_count = idt_ntb_mw_count, + .mw_get_align = idt_ntb_mw_get_align, + .peer_mw_count = idt_ntb_peer_mw_count, + .peer_mw_get_addr = idt_ntb_peer_mw_get_addr, + .peer_mw_set_trans = idt_ntb_peer_mw_set_trans, + .peer_mw_clear_trans = idt_ntb_peer_mw_clear_trans, + .db_valid_mask = idt_ntb_db_valid_mask, + .db_read = idt_ntb_db_read, + .db_clear = idt_ntb_db_clear, + .db_read_mask = idt_ntb_db_read_mask, + .db_set_mask = idt_ntb_db_set_mask, + .db_clear_mask = idt_ntb_db_clear_mask, + .peer_db_set = idt_ntb_peer_db_set, + .msg_count = idt_ntb_msg_count, + .msg_inbits = idt_ntb_msg_inbits, + .msg_outbits = idt_ntb_msg_outbits, + .msg_read_sts = idt_ntb_msg_read_sts, + .msg_clear_sts = idt_ntb_msg_clear_sts, + .msg_set_mask = idt_ntb_msg_set_mask, + .msg_clear_mask = idt_ntb_msg_clear_mask, + .msg_read = idt_ntb_msg_read, + .peer_msg_write = idt_ntb_peer_msg_write +}; + +/* + * idt_register_device() - register IDT NTB device + * @ndev: IDT NTB hardware driver descriptor + * + * Return: zero on success, otherwise a negative error number. + */ +static int idt_register_device(struct idt_ntb_dev *ndev) +{ + int ret; + + /* Initialize the rest of NTB device structure and register it */ + ndev->ntb.ops = &idt_ntb_ops; + ndev->ntb.topo = NTB_TOPO_SWITCH; + + ret = ntb_register_device(&ndev->ntb); + if (ret != 0) { + dev_err(&ndev->ntb.pdev->dev, "Failed to register NTB device"); + return ret; + } + + dev_dbg(&ndev->ntb.pdev->dev, "NTB device successfully registered"); + + return 0; +} + +/* + * idt_unregister_device() - unregister IDT NTB device + * @ndev: IDT NTB hardware driver descriptor + */ +static void idt_unregister_device(struct idt_ntb_dev *ndev) +{ + /* Just unregister the NTB device */ + ntb_unregister_device(&ndev->ntb); + + dev_dbg(&ndev->ntb.pdev->dev, "NTB device unregistered"); +} + +/*============================================================================= + * 10. DebugFS node initialization + *============================================================================= + */ + +static ssize_t idt_dbgfs_info_read(struct file *filp, char __user *ubuf, + size_t count, loff_t *offp); + +/* + * Driver DebugFS info file operations + */ +static const struct file_operations idt_dbgfs_info_ops = { + .owner = THIS_MODULE, + .open = simple_open, + .read = idt_dbgfs_info_read +}; + +/* + * idt_dbgfs_info_read() - DebugFS read info node callback + * @file: File node descriptor. + * @ubuf: User-space buffer to put data to + * @count: Size of the buffer + * @offp: Offset within the buffer + */ +static ssize_t idt_dbgfs_info_read(struct file *filp, char __user *ubuf, + size_t count, loff_t *offp) +{ + struct idt_ntb_dev *ndev = filp->private_data; + unsigned char idx, pidx, cnt; + unsigned long irqflags, mdeg; + ssize_t ret = 0, off = 0; + enum ntb_speed speed; + enum ntb_width width; + char *strbuf; + size_t size; + u32 data; + + /* Lets limit the buffer size the way the Intel/AMD drivers do */ + size = min_t(size_t, count, 0x1000U); + + /* Allocate the memory for the buffer */ + strbuf = kmalloc(size, GFP_KERNEL); + if (strbuf == NULL) + return -ENOMEM; + + /* Put the data into the string buffer */ + off += scnprintf(strbuf + off, size - off, + "\n\t\tIDT NTB device Information:\n\n"); + + /* General local device configurations */ + off += scnprintf(strbuf + off, size - off, + "Local Port %hhu, Partition %hhu\n", ndev->port, ndev->part); + + /* Peer ports information */ + off += scnprintf(strbuf + off, size - off, "Peers:\n"); + for (idx = 0; idx < ndev->peer_cnt; idx++) { + off += scnprintf(strbuf + off, size - off, + "\t%hhu. Port %hhu, Partition %hhu\n", + idx, ndev->peers[idx].port, ndev->peers[idx].part); + } + + /* Links status */ + data = idt_ntb_link_is_up(&ndev->ntb, &speed, &width); + off += scnprintf(strbuf + off, size - off, + "NTB link status\t- 0x%08x, ", data); + off += scnprintf(strbuf + off, size - off, "PCIe Gen %d x%d lanes\n", + speed, width); + + /* Mapping table entries */ + off += scnprintf(strbuf + off, size - off, "NTB Mapping Table:\n"); + for (idx = 0; idx < IDT_MTBL_ENTRY_CNT; idx++) { + spin_lock_irqsave(&ndev->mtbl_lock, irqflags); + idt_nt_write(ndev, IDT_NT_NTMTBLADDR, idx); + data = idt_nt_read(ndev, IDT_NT_NTMTBLDATA); + spin_unlock_irqrestore(&ndev->mtbl_lock, irqflags); + + /* Print valid entries only */ + if (data & IDT_NTMTBLDATA_VALID) { + off += scnprintf(strbuf + off, size - off, + "\t%hhu. Partition %d, Requester ID 0x%04x\n", + idx, GET_FIELD(NTMTBLDATA_PART, data), + GET_FIELD(NTMTBLDATA_REQID, data)); + } + } + off += scnprintf(strbuf + off, size - off, "\n"); + + /* Outbound memory windows information */ + off += scnprintf(strbuf + off, size - off, + "Outbound Memory Windows:\n"); + for (idx = 0; idx < ndev->mw_cnt; idx += cnt) { + data = ndev->mws[idx].type; + cnt = idt_get_mw_count(data); + + /* Print Memory Window information */ + if (data == IDT_MW_DIR) + off += scnprintf(strbuf + off, size - off, + "\t%hhu.\t", idx); + else + off += scnprintf(strbuf + off, size - off, + "\t%hhu-%d.\t", idx, idx + cnt - 1); + + off += scnprintf(strbuf + off, size - off, "%s BAR%hhu, ", + idt_get_mw_name(data), ndev->mws[idx].bar); + + off += scnprintf(strbuf + off, size - off, + "Address align 0x%08llx, ", ndev->mws[idx].addr_align); + + off += scnprintf(strbuf + off, size - off, + "Size align 0x%08llx, Size max %llu\n", + ndev->mws[idx].size_align, ndev->mws[idx].size_max); + } + + /* Inbound memory windows information */ + for (pidx = 0; pidx < ndev->peer_cnt; pidx++) { + off += scnprintf(strbuf + off, size - off, + "Inbound Memory Windows for peer %hhu (Port %hhu):\n", + pidx, ndev->peers[pidx].port); + + /* Print Memory Windows information */ + for (idx = 0; idx < ndev->peers[pidx].mw_cnt; idx += cnt) { + data = ndev->peers[pidx].mws[idx].type; + cnt = idt_get_mw_count(data); + + if (data == IDT_MW_DIR) + off += scnprintf(strbuf + off, size - off, + "\t%hhu.\t", idx); + else + off += scnprintf(strbuf + off, size - off, + "\t%hhu-%d.\t", idx, idx + cnt - 1); + + off += scnprintf(strbuf + off, size - off, + "%s BAR%hhu, ", idt_get_mw_name(data), + ndev->peers[pidx].mws[idx].bar); + + off += scnprintf(strbuf + off, size - off, + "Address align 0x%08llx, ", + ndev->peers[pidx].mws[idx].addr_align); + + off += scnprintf(strbuf + off, size - off, + "Size align 0x%08llx, Size max %llu\n", + ndev->peers[pidx].mws[idx].size_align, + ndev->peers[pidx].mws[idx].size_max); + } + } + off += scnprintf(strbuf + off, size - off, "\n"); + + /* Doorbell information */ + data = idt_sw_read(ndev, IDT_SW_GDBELLSTS); + off += scnprintf(strbuf + off, size - off, + "Global Doorbell state\t- 0x%08x\n", data); + data = idt_ntb_db_read(&ndev->ntb); + off += scnprintf(strbuf + off, size - off, + "Local Doorbell state\t- 0x%08x\n", data); + data = idt_nt_read(ndev, IDT_NT_INDBELLMSK); + off += scnprintf(strbuf + off, size - off, + "Local Doorbell mask\t- 0x%08x\n", data); + off += scnprintf(strbuf + off, size - off, "\n"); + + /* Messaging information */ + off += scnprintf(strbuf + off, size - off, + "Message event valid\t- 0x%08x\n", IDT_MSG_MASK); + data = idt_ntb_msg_read_sts(&ndev->ntb); + off += scnprintf(strbuf + off, size - off, + "Message event status\t- 0x%08x\n", data); + data = idt_nt_read(ndev, IDT_NT_MSGSTSMSK); + off += scnprintf(strbuf + off, size - off, + "Message event mask\t- 0x%08x\n", data); + off += scnprintf(strbuf + off, size - off, + "Message data:\n"); + for (idx = 0; idx < IDT_MSG_CNT; idx++) { + int src; + data = idt_ntb_msg_read(&ndev->ntb, &src, idx); + off += scnprintf(strbuf + off, size - off, + "\t%hhu. 0x%08x from peer %d (Port %hhu)\n", + idx, data, src, ndev->peers[src].port); + } + off += scnprintf(strbuf + off, size - off, "\n"); + + /* Current temperature */ + idt_read_temp(ndev, IDT_TEMP_CUR, &mdeg); + off += scnprintf(strbuf + off, size - off, + "Switch temperature\t\t- %hhd.%hhuC\n", + idt_get_deg(mdeg), idt_get_deg_frac(mdeg)); + + /* Copy the buffer to the User Space */ + ret = simple_read_from_buffer(ubuf, count, offp, strbuf, off); + kfree(strbuf); + + return ret; +} + +/* + * idt_init_dbgfs() - initialize DebugFS node + * @ndev: IDT NTB hardware driver descriptor + * + * Return: zero on success, otherwise a negative error number. + */ +static int idt_init_dbgfs(struct idt_ntb_dev *ndev) +{ + char devname[64]; + + /* If the top directory is not created then do nothing */ + if (IS_ERR_OR_NULL(dbgfs_topdir)) { + dev_info(&ndev->ntb.pdev->dev, "Top DebugFS directory absent"); + return PTR_ERR_OR_ZERO(dbgfs_topdir); + } + + /* Create the info file node */ + snprintf(devname, 64, "info:%s", pci_name(ndev->ntb.pdev)); + ndev->dbgfs_info = debugfs_create_file(devname, 0400, dbgfs_topdir, + ndev, &idt_dbgfs_info_ops); + if (IS_ERR(ndev->dbgfs_info)) { + dev_dbg(&ndev->ntb.pdev->dev, "Failed to create DebugFS node"); + return PTR_ERR(ndev->dbgfs_info); + } + + dev_dbg(&ndev->ntb.pdev->dev, "NTB device DebugFS node created"); + + return 0; +} + +/* + * idt_deinit_dbgfs() - deinitialize DebugFS node + * @ndev: IDT NTB hardware driver descriptor + * + * Just discard the info node from DebugFS + */ +static void idt_deinit_dbgfs(struct idt_ntb_dev *ndev) +{ + debugfs_remove(ndev->dbgfs_info); + + dev_dbg(&ndev->ntb.pdev->dev, "NTB device DebugFS node discarded"); +} + +/*============================================================================= + * 11. Basic PCIe device initialization + *============================================================================= + */ + +/* + * idt_check_setup() - Check whether the IDT PCIe-swtich is properly + * pre-initialized + * @pdev: Pointer to the PCI device descriptor + * + * Return: zero on success, otherwise a negative error number. + */ +static int idt_check_setup(struct pci_dev *pdev) +{ + u32 data; + int ret; + + /* Read the BARSETUP0 */ + ret = pci_read_config_dword(pdev, IDT_NT_BARSETUP0, &data); + if (ret != 0) { + dev_err(&pdev->dev, + "Failed to read BARSETUP0 config register"); + return ret; + } + + /* Check whether the BAR0 register is enabled to be of config space */ + if (!(data & IDT_BARSETUP_EN) || !(data & IDT_BARSETUP_MODE_CFG)) { + dev_err(&pdev->dev, "BAR0 doesn't map config space"); + return -EINVAL; + } + + /* Configuration space BAR0 must have certain size */ + if ((data & IDT_BARSETUP_SIZE_MASK) != IDT_BARSETUP_SIZE_CFG) { + dev_err(&pdev->dev, "Invalid size of config space"); + return -EINVAL; + } + + dev_dbg(&pdev->dev, "NTB device pre-initialized correctly"); + + return 0; +} + +/* + * Create the IDT PCIe-switch driver descriptor + * @pdev: Pointer to the PCI device descriptor + * @id: IDT PCIe-device configuration + * + * It just allocates a memory for IDT PCIe-switch device structure and + * initializes some commonly used fields. + * + * No need of release method, since managed device resource is used for + * memory allocation. + * + * Return: pointer to the descriptor, otherwise a negative error number. + */ +static struct idt_ntb_dev *idt_create_dev(struct pci_dev *pdev, + const struct pci_device_id *id) +{ + struct idt_ntb_dev *ndev; + + /* Allocate memory for the IDT PCIe-device descriptor */ + ndev = devm_kzalloc(&pdev->dev, sizeof(*ndev), GFP_KERNEL); + if (!ndev) { + dev_err(&pdev->dev, "Memory allocation failed for descriptor"); + return ERR_PTR(-ENOMEM); + } + + /* Save the IDT PCIe-switch ports configuration */ + ndev->swcfg = (struct idt_89hpes_cfg *)id->driver_data; + /* Save the PCI-device pointer inside the NTB device structure */ + ndev->ntb.pdev = pdev; + + /* Initialize spin locker of Doorbell, Message and GASA registers */ + spin_lock_init(&ndev->db_mask_lock); + spin_lock_init(&ndev->msg_mask_lock); + spin_lock_init(&ndev->gasa_lock); + + dev_info(&pdev->dev, "IDT %s discovered", ndev->swcfg->name); + + dev_dbg(&pdev->dev, "NTB device descriptor created"); + + return ndev; +} + +/* + * idt_init_pci() - initialize the basic PCI-related subsystem + * @ndev: Pointer to the IDT PCIe-switch driver descriptor + * + * Managed device resources will be freed automatically in case of failure or + * driver detachment. + * + * Return: zero on success, otherwise negative error number. + */ +static int idt_init_pci(struct idt_ntb_dev *ndev) +{ + struct pci_dev *pdev = ndev->ntb.pdev; + int ret; + + /* Initialize the bit mask of PCI/NTB DMA */ + ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64)); + if (ret != 0) { + ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32)); + if (ret != 0) { + dev_err(&pdev->dev, "Failed to set DMA bit mask\n"); + return ret; + } + dev_warn(&pdev->dev, "Cannot set DMA highmem bit mask\n"); + } + + /* + * Enable the device advanced error reporting. It's not critical to + * have AER disabled in the kernel. + */ + ret = pci_enable_pcie_error_reporting(pdev); + if (ret != 0) + dev_warn(&pdev->dev, "PCIe AER capability disabled\n"); + else /* Cleanup nonfatal error status before getting to init */ + pci_aer_clear_nonfatal_status(pdev); + + /* First enable the PCI device */ + ret = pcim_enable_device(pdev); + if (ret != 0) { + dev_err(&pdev->dev, "Failed to enable PCIe device\n"); + goto err_disable_aer; + } + + /* + * Enable the bus mastering, which effectively enables MSI IRQs and + * Request TLPs translation + */ + pci_set_master(pdev); + + /* Request all BARs resources and map BAR0 only */ + ret = pcim_iomap_regions_request_all(pdev, 1, NTB_NAME); + if (ret != 0) { + dev_err(&pdev->dev, "Failed to request resources\n"); + goto err_clear_master; + } + + /* Retrieve virtual address of BAR0 - PCI configuration space */ + ndev->cfgspc = pcim_iomap_table(pdev)[0]; + + /* Put the IDT driver data pointer to the PCI-device private pointer */ + pci_set_drvdata(pdev, ndev); + + dev_dbg(&pdev->dev, "NT-function PCIe interface initialized"); + + return 0; + +err_clear_master: + pci_clear_master(pdev); +err_disable_aer: + (void)pci_disable_pcie_error_reporting(pdev); + + return ret; +} + +/* + * idt_deinit_pci() - deinitialize the basic PCI-related subsystem + * @ndev: Pointer to the IDT PCIe-switch driver descriptor + * + * Managed resources will be freed on the driver detachment + */ +static void idt_deinit_pci(struct idt_ntb_dev *ndev) +{ + struct pci_dev *pdev = ndev->ntb.pdev; + + /* Clean up the PCI-device private data pointer */ + pci_set_drvdata(pdev, NULL); + + /* Clear the bus master disabling the Request TLPs translation */ + pci_clear_master(pdev); + + /* Disable the AER capability */ + (void)pci_disable_pcie_error_reporting(pdev); + + dev_dbg(&pdev->dev, "NT-function PCIe interface cleared"); +} + +/*=========================================================================== + * 12. PCI bus callback functions + *=========================================================================== + */ + +/* + * idt_pci_probe() - PCI device probe callback + * @pdev: Pointer to PCI device structure + * @id: PCIe device custom descriptor + * + * Return: zero on success, otherwise negative error number + */ +static int idt_pci_probe(struct pci_dev *pdev, + const struct pci_device_id *id) +{ + struct idt_ntb_dev *ndev; + int ret; + + /* Check whether IDT PCIe-switch is properly pre-initialized */ + ret = idt_check_setup(pdev); + if (ret != 0) + return ret; + + /* Allocate the memory for IDT NTB device data */ + ndev = idt_create_dev(pdev, id); + if (IS_ERR(ndev)) + return PTR_ERR(ndev); + + /* Initialize the basic PCI subsystem of the device */ + ret = idt_init_pci(ndev); + if (ret != 0) + return ret; + + /* Scan ports of the IDT PCIe-switch */ + (void)idt_scan_ports(ndev); + + /* Initialize NTB link events subsystem */ + idt_init_link(ndev); + + /* Initialize MWs subsystem */ + ret = idt_init_mws(ndev); + if (ret != 0) + goto err_deinit_link; + + /* Initialize Messaging subsystem */ + idt_init_msg(ndev); + + /* Initialize hwmon interface */ + idt_init_temp(ndev); + + /* Initialize IDT interrupts handler */ + ret = idt_init_isr(ndev); + if (ret != 0) + goto err_deinit_link; + + /* Register IDT NTB devices on the NTB bus */ + ret = idt_register_device(ndev); + if (ret != 0) + goto err_deinit_isr; + + /* Initialize DebugFS info node */ + (void)idt_init_dbgfs(ndev); + + /* IDT PCIe-switch NTB driver is finally initialized */ + dev_info(&pdev->dev, "IDT NTB device is ready"); + + /* May the force be with us... */ + return 0; + +err_deinit_isr: + idt_deinit_isr(ndev); +err_deinit_link: + idt_deinit_link(ndev); + idt_deinit_pci(ndev); + + return ret; +} + +/* + * idt_pci_probe() - PCI device remove callback + * @pdev: Pointer to PCI device structure + */ +static void idt_pci_remove(struct pci_dev *pdev) +{ + struct idt_ntb_dev *ndev = pci_get_drvdata(pdev); + + /* Deinit the DebugFS node */ + idt_deinit_dbgfs(ndev); + + /* Unregister NTB device */ + idt_unregister_device(ndev); + + /* Stop the interrupts handling */ + idt_deinit_isr(ndev); + + /* Deinitialize link event subsystem */ + idt_deinit_link(ndev); + + /* Deinit basic PCI subsystem */ + idt_deinit_pci(ndev); + + /* IDT PCIe-switch NTB driver is finally initialized */ + dev_info(&pdev->dev, "IDT NTB device is removed"); + + /* Sayonara... */ +} + +/* + * IDT PCIe-switch models ports configuration structures + */ +static const struct idt_89hpes_cfg idt_89hpes24nt6ag2_config = { + .name = "89HPES24NT6AG2", + .port_cnt = 6, .ports = {0, 2, 4, 6, 8, 12} +}; +static const struct idt_89hpes_cfg idt_89hpes32nt8ag2_config = { + .name = "89HPES32NT8AG2", + .port_cnt = 8, .ports = {0, 2, 4, 6, 8, 12, 16, 20} +}; +static const struct idt_89hpes_cfg idt_89hpes32nt8bg2_config = { + .name = "89HPES32NT8BG2", + .port_cnt = 8, .ports = {0, 2, 4, 6, 8, 12, 16, 20} +}; +static const struct idt_89hpes_cfg idt_89hpes12nt12g2_config = { + .name = "89HPES12NT12G2", + .port_cnt = 3, .ports = {0, 8, 16} +}; +static const struct idt_89hpes_cfg idt_89hpes16nt16g2_config = { + .name = "89HPES16NT16G2", + .port_cnt = 4, .ports = {0, 8, 12, 16} +}; +static const struct idt_89hpes_cfg idt_89hpes24nt24g2_config = { + .name = "89HPES24NT24G2", + .port_cnt = 8, .ports = {0, 2, 4, 6, 8, 12, 16, 20} +}; +static const struct idt_89hpes_cfg idt_89hpes32nt24ag2_config = { + .name = "89HPES32NT24AG2", + .port_cnt = 8, .ports = {0, 2, 4, 6, 8, 12, 16, 20} +}; +static const struct idt_89hpes_cfg idt_89hpes32nt24bg2_config = { + .name = "89HPES32NT24BG2", + .port_cnt = 8, .ports = {0, 2, 4, 6, 8, 12, 16, 20} +}; + +/* + * PCI-ids table of the supported IDT PCIe-switch devices + */ +static const struct pci_device_id idt_pci_tbl[] = { + {IDT_PCI_DEVICE_IDS(89HPES24NT6AG2, idt_89hpes24nt6ag2_config)}, + {IDT_PCI_DEVICE_IDS(89HPES32NT8AG2, idt_89hpes32nt8ag2_config)}, + {IDT_PCI_DEVICE_IDS(89HPES32NT8BG2, idt_89hpes32nt8bg2_config)}, + {IDT_PCI_DEVICE_IDS(89HPES12NT12G2, idt_89hpes12nt12g2_config)}, + {IDT_PCI_DEVICE_IDS(89HPES16NT16G2, idt_89hpes16nt16g2_config)}, + {IDT_PCI_DEVICE_IDS(89HPES24NT24G2, idt_89hpes24nt24g2_config)}, + {IDT_PCI_DEVICE_IDS(89HPES32NT24AG2, idt_89hpes32nt24ag2_config)}, + {IDT_PCI_DEVICE_IDS(89HPES32NT24BG2, idt_89hpes32nt24bg2_config)}, + {0} +}; +MODULE_DEVICE_TABLE(pci, idt_pci_tbl); + +/* + * IDT PCIe-switch NT-function device driver structure definition + */ +static struct pci_driver idt_pci_driver = { + .name = KBUILD_MODNAME, + .probe = idt_pci_probe, + .remove = idt_pci_remove, + .id_table = idt_pci_tbl, +}; + +static int __init idt_pci_driver_init(void) +{ + int ret; + pr_info("%s %s\n", NTB_DESC, NTB_VER); + + /* Create the top DebugFS directory if the FS is initialized */ + if (debugfs_initialized()) + dbgfs_topdir = debugfs_create_dir(KBUILD_MODNAME, NULL); + + /* Register the NTB hardware driver to handle the PCI device */ + ret = pci_register_driver(&idt_pci_driver); + if (ret) + debugfs_remove_recursive(dbgfs_topdir); + + return ret; +} +module_init(idt_pci_driver_init); + +static void __exit idt_pci_driver_exit(void) +{ + /* Unregister the NTB hardware driver */ + pci_unregister_driver(&idt_pci_driver); + + /* Discard the top DebugFS directory */ + debugfs_remove_recursive(dbgfs_topdir); +} +module_exit(idt_pci_driver_exit); + |