linux/drivers/spi/spi-pci1xxxx.c
Kees Cook c40897f473
spi: mchp-pci1xxxx: Annotate struct pci1xxxx_spi with __counted_by
Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).

As found with Coccinelle[1], add __counted_by for struct pci1xxxx_spi.

[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci

Cc: Mark Brown <broonie@kernel.org>
Cc: linux-spi@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20230922175322.work.170-kees@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>
2023-09-22 19:01:40 +01:00

470 lines
14 KiB
C

// SPDX-License-Identifier: GPL-2.0
// PCI1xxxx SPI driver
// Copyright (C) 2022 Microchip Technology Inc.
// Authors: Tharun Kumar P <tharunkumar.pasumarthi@microchip.com>
// Kumaravel Thiagarajan <Kumaravel.Thiagarajan@microchip.com>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/spi/spi.h>
#include <linux/delay.h>
#define DRV_NAME "spi-pci1xxxx"
#define SYS_FREQ_DEFAULT (62500000)
#define PCI1XXXX_SPI_MAX_CLOCK_HZ (30000000)
#define PCI1XXXX_SPI_CLK_20MHZ (20000000)
#define PCI1XXXX_SPI_CLK_15MHZ (15000000)
#define PCI1XXXX_SPI_CLK_12MHZ (12000000)
#define PCI1XXXX_SPI_CLK_10MHZ (10000000)
#define PCI1XXXX_SPI_MIN_CLOCK_HZ (2000000)
#define PCI1XXXX_SPI_BUFFER_SIZE (320)
#define SPI_MST_CTL_DEVSEL_MASK (GENMASK(27, 25))
#define SPI_MST_CTL_CMD_LEN_MASK (GENMASK(16, 8))
#define SPI_MST_CTL_SPEED_MASK (GENMASK(7, 5))
#define SPI_MSI_VECTOR_SEL_MASK (GENMASK(4, 4))
#define SPI_MST_CTL_FORCE_CE (BIT(4))
#define SPI_MST_CTL_MODE_SEL (BIT(2))
#define SPI_MST_CTL_GO (BIT(0))
#define SPI_MST1_ADDR_BASE (0x800)
/* x refers to SPI Host Controller HW instance id in the below macros - 0 or 1 */
#define SPI_MST_CMD_BUF_OFFSET(x) (((x) * SPI_MST1_ADDR_BASE) + 0x00)
#define SPI_MST_RSP_BUF_OFFSET(x) (((x) * SPI_MST1_ADDR_BASE) + 0x200)
#define SPI_MST_CTL_REG_OFFSET(x) (((x) * SPI_MST1_ADDR_BASE) + 0x400)
#define SPI_MST_EVENT_REG_OFFSET(x) (((x) * SPI_MST1_ADDR_BASE) + 0x420)
#define SPI_MST_EVENT_MASK_REG_OFFSET(x) (((x) * SPI_MST1_ADDR_BASE) + 0x424)
#define SPI_MST_PAD_CTL_REG_OFFSET(x) (((x) * SPI_MST1_ADDR_BASE) + 0x460)
#define SPIALERT_MST_DB_REG_OFFSET(x) (((x) * SPI_MST1_ADDR_BASE) + 0x464)
#define SPIALERT_MST_VAL_REG_OFFSET(x) (((x) * SPI_MST1_ADDR_BASE) + 0x468)
#define SPI_PCI_CTRL_REG_OFFSET(x) (((x) * SPI_MST1_ADDR_BASE) + 0x480)
#define PCI1XXXX_IRQ_FLAGS (IRQF_NO_SUSPEND | IRQF_TRIGGER_NONE)
#define SPI_MAX_DATA_LEN 320
#define PCI1XXXX_SPI_TIMEOUT (msecs_to_jiffies(100))
#define SPI_INTR BIT(8)
#define SPI_FORCE_CE BIT(4)
#define SPI_CHIP_SEL_COUNT 7
#define VENDOR_ID_MCHP 0x1055
#define SPI_SUSPEND_CONFIG 0x101
#define SPI_RESUME_CONFIG 0x203
struct pci1xxxx_spi_internal {
u8 hw_inst;
bool spi_xfer_in_progress;
int irq;
struct completion spi_xfer_done;
struct spi_controller *spi_host;
struct pci1xxxx_spi *parent;
struct {
unsigned int dev_sel : 3;
unsigned int msi_vector_sel : 1;
} prev_val;
};
struct pci1xxxx_spi {
struct pci_dev *dev;
u8 total_hw_instances;
void __iomem *reg_base;
struct pci1xxxx_spi_internal *spi_int[] __counted_by(total_hw_instances);
};
static const struct pci_device_id pci1xxxx_spi_pci_id_table[] = {
{ PCI_DEVICE_SUB(VENDOR_ID_MCHP, 0xa004, PCI_ANY_ID, 0x0001), 0, 0, 0x02},
{ PCI_DEVICE_SUB(VENDOR_ID_MCHP, 0xa004, PCI_ANY_ID, 0x0002), 0, 0, 0x01},
{ PCI_DEVICE_SUB(VENDOR_ID_MCHP, 0xa004, PCI_ANY_ID, 0x0003), 0, 0, 0x11},
{ PCI_DEVICE_SUB(VENDOR_ID_MCHP, 0xa004, PCI_ANY_ID, PCI_ANY_ID), 0, 0, 0x01},
{ PCI_DEVICE_SUB(VENDOR_ID_MCHP, 0xa014, PCI_ANY_ID, 0x0001), 0, 0, 0x02},
{ PCI_DEVICE_SUB(VENDOR_ID_MCHP, 0xa014, PCI_ANY_ID, 0x0002), 0, 0, 0x01},
{ PCI_DEVICE_SUB(VENDOR_ID_MCHP, 0xa014, PCI_ANY_ID, 0x0003), 0, 0, 0x11},
{ PCI_DEVICE_SUB(VENDOR_ID_MCHP, 0xa014, PCI_ANY_ID, PCI_ANY_ID), 0, 0, 0x01},
{ PCI_DEVICE_SUB(VENDOR_ID_MCHP, 0xa024, PCI_ANY_ID, 0x0001), 0, 0, 0x02},
{ PCI_DEVICE_SUB(VENDOR_ID_MCHP, 0xa024, PCI_ANY_ID, 0x0002), 0, 0, 0x01},
{ PCI_DEVICE_SUB(VENDOR_ID_MCHP, 0xa024, PCI_ANY_ID, 0x0003), 0, 0, 0x11},
{ PCI_DEVICE_SUB(VENDOR_ID_MCHP, 0xa024, PCI_ANY_ID, PCI_ANY_ID), 0, 0, 0x01},
{ PCI_DEVICE_SUB(VENDOR_ID_MCHP, 0xa034, PCI_ANY_ID, 0x0001), 0, 0, 0x02},
{ PCI_DEVICE_SUB(VENDOR_ID_MCHP, 0xa034, PCI_ANY_ID, 0x0002), 0, 0, 0x01},
{ PCI_DEVICE_SUB(VENDOR_ID_MCHP, 0xa034, PCI_ANY_ID, 0x0003), 0, 0, 0x11},
{ PCI_DEVICE_SUB(VENDOR_ID_MCHP, 0xa034, PCI_ANY_ID, PCI_ANY_ID), 0, 0, 0x01},
{ PCI_DEVICE_SUB(VENDOR_ID_MCHP, 0xa044, PCI_ANY_ID, 0x0001), 0, 0, 0x02},
{ PCI_DEVICE_SUB(VENDOR_ID_MCHP, 0xa044, PCI_ANY_ID, 0x0002), 0, 0, 0x01},
{ PCI_DEVICE_SUB(VENDOR_ID_MCHP, 0xa044, PCI_ANY_ID, 0x0003), 0, 0, 0x11},
{ PCI_DEVICE_SUB(VENDOR_ID_MCHP, 0xa044, PCI_ANY_ID, PCI_ANY_ID), 0, 0, 0x01},
{ 0, }
};
MODULE_DEVICE_TABLE(pci, pci1xxxx_spi_pci_id_table);
static void pci1xxxx_spi_set_cs(struct spi_device *spi, bool enable)
{
struct pci1xxxx_spi_internal *p = spi_controller_get_devdata(spi->controller);
struct pci1xxxx_spi *par = p->parent;
u32 regval;
/* Set the DEV_SEL bits of the SPI_MST_CTL_REG */
regval = readl(par->reg_base + SPI_MST_CTL_REG_OFFSET(p->hw_inst));
if (!enable) {
regval |= SPI_FORCE_CE;
regval &= ~SPI_MST_CTL_DEVSEL_MASK;
regval |= (spi_get_chipselect(spi, 0) << 25);
} else {
regval &= ~SPI_FORCE_CE;
}
writel(regval, par->reg_base + SPI_MST_CTL_REG_OFFSET(p->hw_inst));
}
static u8 pci1xxxx_get_clock_div(u32 hz)
{
u8 val = 0;
if (hz >= PCI1XXXX_SPI_MAX_CLOCK_HZ)
val = 2;
else if ((hz < PCI1XXXX_SPI_MAX_CLOCK_HZ) && (hz >= PCI1XXXX_SPI_CLK_20MHZ))
val = 3;
else if ((hz < PCI1XXXX_SPI_CLK_20MHZ) && (hz >= PCI1XXXX_SPI_CLK_15MHZ))
val = 4;
else if ((hz < PCI1XXXX_SPI_CLK_15MHZ) && (hz >= PCI1XXXX_SPI_CLK_12MHZ))
val = 5;
else if ((hz < PCI1XXXX_SPI_CLK_12MHZ) && (hz >= PCI1XXXX_SPI_CLK_10MHZ))
val = 6;
else if ((hz < PCI1XXXX_SPI_CLK_10MHZ) && (hz >= PCI1XXXX_SPI_MIN_CLOCK_HZ))
val = 7;
else
val = 2;
return val;
}
static int pci1xxxx_spi_transfer_one(struct spi_controller *spi_ctlr,
struct spi_device *spi, struct spi_transfer *xfer)
{
struct pci1xxxx_spi_internal *p = spi_controller_get_devdata(spi_ctlr);
int mode, len, loop_iter, transfer_len;
struct pci1xxxx_spi *par = p->parent;
unsigned long bytes_transfered;
unsigned long bytes_recvd;
unsigned long loop_count;
u8 *rx_buf, result;
const u8 *tx_buf;
u32 regval;
u8 clkdiv;
p->spi_xfer_in_progress = true;
mode = spi->mode;
clkdiv = pci1xxxx_get_clock_div(xfer->speed_hz);
tx_buf = xfer->tx_buf;
rx_buf = xfer->rx_buf;
transfer_len = xfer->len;
regval = readl(par->reg_base + SPI_MST_EVENT_REG_OFFSET(p->hw_inst));
writel(regval, par->reg_base + SPI_MST_EVENT_REG_OFFSET(p->hw_inst));
if (tx_buf) {
bytes_transfered = 0;
bytes_recvd = 0;
loop_count = transfer_len / SPI_MAX_DATA_LEN;
if (transfer_len % SPI_MAX_DATA_LEN != 0)
loop_count += 1;
for (loop_iter = 0; loop_iter < loop_count; loop_iter++) {
len = SPI_MAX_DATA_LEN;
if ((transfer_len % SPI_MAX_DATA_LEN != 0) &&
(loop_iter == loop_count - 1))
len = transfer_len % SPI_MAX_DATA_LEN;
reinit_completion(&p->spi_xfer_done);
memcpy_toio(par->reg_base + SPI_MST_CMD_BUF_OFFSET(p->hw_inst),
&tx_buf[bytes_transfered], len);
bytes_transfered += len;
regval = readl(par->reg_base +
SPI_MST_CTL_REG_OFFSET(p->hw_inst));
regval &= ~(SPI_MST_CTL_MODE_SEL | SPI_MST_CTL_CMD_LEN_MASK |
SPI_MST_CTL_SPEED_MASK);
if (mode == SPI_MODE_3)
regval |= SPI_MST_CTL_MODE_SEL;
else
regval &= ~SPI_MST_CTL_MODE_SEL;
regval |= (clkdiv << 5);
regval &= ~SPI_MST_CTL_CMD_LEN_MASK;
regval |= (len << 8);
writel(regval, par->reg_base +
SPI_MST_CTL_REG_OFFSET(p->hw_inst));
regval = readl(par->reg_base +
SPI_MST_CTL_REG_OFFSET(p->hw_inst));
regval |= SPI_MST_CTL_GO;
writel(regval, par->reg_base +
SPI_MST_CTL_REG_OFFSET(p->hw_inst));
/* Wait for DMA_TERM interrupt */
result = wait_for_completion_timeout(&p->spi_xfer_done,
PCI1XXXX_SPI_TIMEOUT);
if (!result)
return -ETIMEDOUT;
if (rx_buf) {
memcpy_fromio(&rx_buf[bytes_recvd], par->reg_base +
SPI_MST_RSP_BUF_OFFSET(p->hw_inst), len);
bytes_recvd += len;
}
}
}
p->spi_xfer_in_progress = false;
return 0;
}
static irqreturn_t pci1xxxx_spi_isr(int irq, void *dev)
{
struct pci1xxxx_spi_internal *p = dev;
irqreturn_t spi_int_fired = IRQ_NONE;
u32 regval;
/* Clear the SPI GO_BIT Interrupt */
regval = readl(p->parent->reg_base + SPI_MST_EVENT_REG_OFFSET(p->hw_inst));
if (regval & SPI_INTR) {
/* Clear xfer_done */
complete(&p->spi_xfer_done);
spi_int_fired = IRQ_HANDLED;
}
writel(regval, p->parent->reg_base + SPI_MST_EVENT_REG_OFFSET(p->hw_inst));
return spi_int_fired;
}
static int pci1xxxx_spi_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
{
u8 hw_inst_cnt, iter, start, only_sec_inst;
struct pci1xxxx_spi_internal *spi_sub_ptr;
struct device *dev = &pdev->dev;
struct pci1xxxx_spi *spi_bus;
struct spi_controller *spi_host;
u32 regval;
int ret;
hw_inst_cnt = ent->driver_data & 0x0f;
start = (ent->driver_data & 0xf0) >> 4;
if (start == 1)
only_sec_inst = 1;
else
only_sec_inst = 0;
spi_bus = devm_kzalloc(&pdev->dev,
struct_size(spi_bus, spi_int, hw_inst_cnt),
GFP_KERNEL);
if (!spi_bus)
return -ENOMEM;
spi_bus->dev = pdev;
spi_bus->total_hw_instances = hw_inst_cnt;
pci_set_master(pdev);
for (iter = 0; iter < hw_inst_cnt; iter++) {
spi_bus->spi_int[iter] = devm_kzalloc(&pdev->dev,
sizeof(struct pci1xxxx_spi_internal),
GFP_KERNEL);
spi_sub_ptr = spi_bus->spi_int[iter];
spi_sub_ptr->spi_host = devm_spi_alloc_host(dev, sizeof(struct spi_controller));
if (!spi_sub_ptr->spi_host)
return -ENOMEM;
spi_sub_ptr->parent = spi_bus;
spi_sub_ptr->spi_xfer_in_progress = false;
if (!iter) {
ret = pcim_enable_device(pdev);
if (ret)
return -ENOMEM;
ret = pci_request_regions(pdev, DRV_NAME);
if (ret)
return -ENOMEM;
spi_bus->reg_base = pcim_iomap(pdev, 0, pci_resource_len(pdev, 0));
if (!spi_bus->reg_base) {
ret = -EINVAL;
goto error;
}
ret = pci_alloc_irq_vectors(pdev, hw_inst_cnt, hw_inst_cnt,
PCI_IRQ_ALL_TYPES);
if (ret < 0) {
dev_err(&pdev->dev, "Error allocating MSI vectors\n");
goto error;
}
init_completion(&spi_sub_ptr->spi_xfer_done);
/* Initialize Interrupts - SPI_INT */
regval = readl(spi_bus->reg_base +
SPI_MST_EVENT_MASK_REG_OFFSET(spi_sub_ptr->hw_inst));
regval &= ~SPI_INTR;
writel(regval, spi_bus->reg_base +
SPI_MST_EVENT_MASK_REG_OFFSET(spi_sub_ptr->hw_inst));
spi_sub_ptr->irq = pci_irq_vector(pdev, 0);
ret = devm_request_irq(&pdev->dev, spi_sub_ptr->irq,
pci1xxxx_spi_isr, PCI1XXXX_IRQ_FLAGS,
pci_name(pdev), spi_sub_ptr);
if (ret < 0) {
dev_err(&pdev->dev, "Unable to request irq : %d",
spi_sub_ptr->irq);
ret = -ENODEV;
goto error;
}
/* This register is only applicable for 1st instance */
regval = readl(spi_bus->reg_base + SPI_PCI_CTRL_REG_OFFSET(0));
if (!only_sec_inst)
regval |= (BIT(4));
else
regval &= ~(BIT(4));
writel(regval, spi_bus->reg_base + SPI_PCI_CTRL_REG_OFFSET(0));
}
spi_sub_ptr->hw_inst = start++;
if (iter == 1) {
init_completion(&spi_sub_ptr->spi_xfer_done);
/* Initialize Interrupts - SPI_INT */
regval = readl(spi_bus->reg_base +
SPI_MST_EVENT_MASK_REG_OFFSET(spi_sub_ptr->hw_inst));
regval &= ~SPI_INTR;
writel(regval, spi_bus->reg_base +
SPI_MST_EVENT_MASK_REG_OFFSET(spi_sub_ptr->hw_inst));
spi_sub_ptr->irq = pci_irq_vector(pdev, iter);
ret = devm_request_irq(&pdev->dev, spi_sub_ptr->irq,
pci1xxxx_spi_isr, PCI1XXXX_IRQ_FLAGS,
pci_name(pdev), spi_sub_ptr);
if (ret < 0) {
dev_err(&pdev->dev, "Unable to request irq : %d",
spi_sub_ptr->irq);
ret = -ENODEV;
goto error;
}
}
spi_host = spi_sub_ptr->spi_host;
spi_host->num_chipselect = SPI_CHIP_SEL_COUNT;
spi_host->mode_bits = SPI_MODE_0 | SPI_MODE_3 | SPI_RX_DUAL |
SPI_TX_DUAL | SPI_LOOP;
spi_host->transfer_one = pci1xxxx_spi_transfer_one;
spi_host->set_cs = pci1xxxx_spi_set_cs;
spi_host->bits_per_word_mask = SPI_BPW_MASK(8);
spi_host->max_speed_hz = PCI1XXXX_SPI_MAX_CLOCK_HZ;
spi_host->min_speed_hz = PCI1XXXX_SPI_MIN_CLOCK_HZ;
spi_host->flags = SPI_CONTROLLER_MUST_TX;
spi_controller_set_devdata(spi_host, spi_sub_ptr);
ret = devm_spi_register_controller(dev, spi_host);
if (ret)
goto error;
}
pci_set_drvdata(pdev, spi_bus);
return 0;
error:
pci_release_regions(pdev);
return ret;
}
static void store_restore_config(struct pci1xxxx_spi *spi_ptr,
struct pci1xxxx_spi_internal *spi_sub_ptr,
u8 inst, bool store)
{
u32 regval;
if (store) {
regval = readl(spi_ptr->reg_base +
SPI_MST_CTL_REG_OFFSET(spi_sub_ptr->hw_inst));
regval &= SPI_MST_CTL_DEVSEL_MASK;
spi_sub_ptr->prev_val.dev_sel = (regval >> 25) & 7;
regval = readl(spi_ptr->reg_base +
SPI_PCI_CTRL_REG_OFFSET(spi_sub_ptr->hw_inst));
regval &= SPI_MSI_VECTOR_SEL_MASK;
spi_sub_ptr->prev_val.msi_vector_sel = (regval >> 4) & 1;
} else {
regval = readl(spi_ptr->reg_base + SPI_MST_CTL_REG_OFFSET(inst));
regval &= ~SPI_MST_CTL_DEVSEL_MASK;
regval |= (spi_sub_ptr->prev_val.dev_sel << 25);
writel(regval,
spi_ptr->reg_base + SPI_MST_CTL_REG_OFFSET(inst));
writel((spi_sub_ptr->prev_val.msi_vector_sel << 4),
spi_ptr->reg_base + SPI_PCI_CTRL_REG_OFFSET(inst));
}
}
static int pci1xxxx_spi_resume(struct device *dev)
{
struct pci1xxxx_spi *spi_ptr = dev_get_drvdata(dev);
struct pci1xxxx_spi_internal *spi_sub_ptr;
u32 regval = SPI_RESUME_CONFIG;
u8 iter;
for (iter = 0; iter < spi_ptr->total_hw_instances; iter++) {
spi_sub_ptr = spi_ptr->spi_int[iter];
spi_controller_resume(spi_sub_ptr->spi_host);
writel(regval, spi_ptr->reg_base +
SPI_MST_EVENT_MASK_REG_OFFSET(iter));
/* Restore config at resume */
store_restore_config(spi_ptr, spi_sub_ptr, iter, 0);
}
return 0;
}
static int pci1xxxx_spi_suspend(struct device *dev)
{
struct pci1xxxx_spi *spi_ptr = dev_get_drvdata(dev);
struct pci1xxxx_spi_internal *spi_sub_ptr;
u32 reg1 = SPI_SUSPEND_CONFIG;
u8 iter;
for (iter = 0; iter < spi_ptr->total_hw_instances; iter++) {
spi_sub_ptr = spi_ptr->spi_int[iter];
while (spi_sub_ptr->spi_xfer_in_progress)
msleep(20);
/* Store existing config before suspend */
store_restore_config(spi_ptr, spi_sub_ptr, iter, 1);
spi_controller_suspend(spi_sub_ptr->spi_host);
writel(reg1, spi_ptr->reg_base +
SPI_MST_EVENT_MASK_REG_OFFSET(iter));
}
return 0;
}
static DEFINE_SIMPLE_DEV_PM_OPS(spi_pm_ops, pci1xxxx_spi_suspend,
pci1xxxx_spi_resume);
static struct pci_driver pci1xxxx_spi_driver = {
.name = DRV_NAME,
.id_table = pci1xxxx_spi_pci_id_table,
.probe = pci1xxxx_spi_probe,
.driver = {
.pm = pm_sleep_ptr(&spi_pm_ops),
},
};
module_pci_driver(pci1xxxx_spi_driver);
MODULE_DESCRIPTION("Microchip Technology Inc. pci1xxxx SPI bus driver");
MODULE_AUTHOR("Tharun Kumar P<tharunkumar.pasumarthi@microchip.com>");
MODULE_AUTHOR("Kumaravel Thiagarajan<kumaravel.thiagarajan@microchip.com>");
MODULE_LICENSE("GPL v2");