On Mon, Jul 27, 2020 at 12:13:44PM +0900, Masahisa Kojima wrote:
> Hi Jarkko,
>
> Thank you for your comments.
>
> On Thu, 23 Jul 2020 at 11:36, Jarkko Sakkinen
> <jarkko.sakkinen@xxxxxxxxxxxxxxx> wrote:
> >
> > On Fri, Jul 17, 2020 at 05:49:31PM +0900, Masahisa Kojima wrote:
> > > When fitted, the SynQuacer platform exposes its SPI TPM via a MMIO
> > > window that is backed by the SPI command sequencer in the SPI bus
> > > controller. This arrangement has the limitation that only byte size
> > > accesses are supported, and so we'll need to provide a separate module
> > > that take this into account.
> > >
> > > Signed-off-by: Ard Biesheuvel <ardb@xxxxxxxxxx>
> > > Signed-off-by: Masahisa Kojima <masahisa.kojima@xxxxxxxxxx>
> > > ---
> > > drivers/char/tpm/Kconfig | 12 ++
> > > drivers/char/tpm/Makefile | 1 +
> > > drivers/char/tpm/tpm_tis_synquacer.c | 209 +++++++++++++++++++++++++++
> > > 3 files changed, 222 insertions(+)
> > > create mode 100644 drivers/char/tpm/tpm_tis_synquacer.c
> > >
> > > diff --git a/drivers/char/tpm/Kconfig b/drivers/char/tpm/Kconfig
> > > index 58b4c573d176..a18c314da211 100644
> > > --- a/drivers/char/tpm/Kconfig
> > > +++ b/drivers/char/tpm/Kconfig
> > > @@ -74,6 +74,18 @@ config TCG_TIS_SPI_CR50
> > > If you have a H1 secure module running Cr50 firmware on SPI bus,
> > > say Yes and it will be accessible from within Linux.
> > >
> > > +config TCG_TIS_SYNQUACER
> > > + tristate "TPM Interface Specification 1.2 Interface / TPM 2.0 FIFO Interface (MMIO - SynQuacer)"
> > > + depends on ARCH_SYNQUACER
> > > + select TCG_TIS_CORE
> > > + help
> > > + If you have a TPM security chip that is compliant with the
> > > + TCG TIS 1.2 TPM specification (TPM1.2) or the TCG PTP FIFO
> > > + specification (TPM2.0) say Yes and it will be accessible from
> > > + within Linux on Socionext SynQuacer platform.
> > > + To compile this driver as a module, choose M here;
> > > + the module will be called tpm_tis_synquacer.
> > > +
> > > config TCG_TIS_I2C_ATMEL
> > > tristate "TPM Interface Specification 1.2 Interface (I2C - Atmel)"
> > > depends on I2C
> > > diff --git a/drivers/char/tpm/Makefile b/drivers/char/tpm/Makefile
> > > index 9567e5197f74..84db4fb3a9c9 100644
> > > --- a/drivers/char/tpm/Makefile
> > > +++ b/drivers/char/tpm/Makefile
> > > @@ -21,6 +21,7 @@ tpm-$(CONFIG_EFI) += eventlog/efi.o
> > > tpm-$(CONFIG_OF) += eventlog/of.o
> > > obj-$(CONFIG_TCG_TIS_CORE) += tpm_tis_core.o
> > > obj-$(CONFIG_TCG_TIS) += tpm_tis.o
> > > +obj-$(CONFIG_TCG_TIS_SYNQUACER) += tpm_tis_synquacer.o
> > >
> > > obj-$(CONFIG_TCG_TIS_SPI) += tpm_tis_spi.o
> > > tpm_tis_spi-y := tpm_tis_spi_main.o
> > > diff --git a/drivers/char/tpm/tpm_tis_synquacer.c b/drivers/char/tpm/tpm_tis_synquacer.c
> > > new file mode 100644
> > > index 000000000000..ac2a1d2a5001
> > > --- /dev/null
> > > +++ b/drivers/char/tpm/tpm_tis_synquacer.c
> > > @@ -0,0 +1,209 @@
> > > +// SPDX-License-Identifier: GPL-2.0
> > > +/*
> > > + * Copyright (C) 2020 Linaro Ltd.
> > > + *
> > > + * This device driver implements MMIO TPM on SynQuacer Platform.
> > > + */
> > > +#include <linux/acpi.h>
> > > +#include <linux/init.h>
> > > +#include <linux/module.h>
> > > +#include <linux/slab.h>
> > > +#include <linux/of.h>
> > > +#include <linux/of_device.h>
> > > +#include <linux/kernel.h>
> > > +#include "tpm.h"
> > > +#include "tpm_tis_core.h"
> > > +
> > > +struct tpm_tis_synquacer_info {
> > > + struct resource res;
> > > + /* irq > 0 means: use irq $irq;
> > > + * irq = 0 means: autoprobe for an irq;
> > > + * irq = -1 means: no irq support
> > > + */
> > > + int irq;
> > > +};
> >
> > According to the coding style, multi-line comments must begin with an
> > empty line.
> >
> > Also it would be preferable to have the comment prepending the struct
> > for easier read:
> >
> > /*
> > * irq > 0 means: use irq $irq;
> > * irq = 0 means: autoprobe for an irq;
> > * irq = -1 means: no irq support
> > */
> > struct tpm_tis_synquacer_info {
>
> I will modify.
>
> >
> > > +
> > > +struct tpm_tis_synquacer_phy {
> > > + struct tpm_tis_data priv;
> > > + void __iomem *iobase;
> > > +};
> > > +
> > > +static inline struct tpm_tis_synquacer_phy *to_tpm_tis_tcg_phy(struct tpm_tis_data *data)
> > > +{
> > > + return container_of(data, struct tpm_tis_synquacer_phy, priv);
> > > +}
> > > +
> > > +static int tpm_tis_synquacer_read_bytes(struct tpm_tis_data *data, u32 addr,
> > > + u16 len, u8 *result)
> > > +{
> > > + struct tpm_tis_synquacer_phy *phy = to_tpm_tis_tcg_phy(data);
> > > +
> > > + while (len--)
> > > + *result++ = ioread8(phy->iobase + addr);
> > > +
> > > + return 0;
> > > +}
> > > +
> > > +static int tpm_tis_synquacer_write_bytes(struct tpm_tis_data *data, u32 addr,
> > > + u16 len, const u8 *value)
> > > +{
> > > + struct tpm_tis_synquacer_phy *phy = to_tpm_tis_tcg_phy(data);
> > > +
> > > + while (len--)
> > > + iowrite8(*value++, phy->iobase + addr);
> > > +
> > > + return 0;
> > > +}
> > > +
> > > +static int tpm_tis_synquacer_read16_bw(struct tpm_tis_data *data,
> > > + u32 addr, u16 *result)
> > > +{
> > > + struct tpm_tis_synquacer_phy *phy = to_tpm_tis_tcg_phy(data);
> > > +
> > > + /*
> > > + * Due to the limitation of SPI controller on SynQuacer,
> > > + * 16/32 bits access must be done in byte-wise and descending order.
> > > + */
> > > + *result = (ioread8(phy->iobase + addr + 1) << 8) |
> > > + (ioread8(phy->iobase + addr));
> > > +
> > > + return 0;
> > > +}
> > > +
> > > +static int tpm_tis_synquacer_read32_bw(struct tpm_tis_data *data,
> > > + u32 addr, u32 *result)
> > > +{
> > > + struct tpm_tis_synquacer_phy *phy = to_tpm_tis_tcg_phy(data);
> > > +
> > > + /*
> > > + * Due to the limitation of SPI controller on SynQuacer,
> > > + * 16/32 bits access must be done in byte-wise and descending order.
> > > + */
> > > + *result = (ioread8(phy->iobase + addr + 3) << 24) |
> > > + (ioread8(phy->iobase + addr + 2) << 16) |
> > > + (ioread8(phy->iobase + addr + 1) << 8) |
> > > + (ioread8(phy->iobase + addr));
> > > +
> > > + return 0;
> > > +}
> > > +
> > > +static int tpm_tis_synquacer_write32_bw(struct tpm_tis_data *data,
> > > + u32 addr, u32 value)
> > > +{
> > > + struct tpm_tis_synquacer_phy *phy = to_tpm_tis_tcg_phy(data);
> > > +
> > > + /*
> > > + * Due to the limitation of SPI controller on SynQuacer,
> > > + * 16/32 bits access must be done in byte-wise and descending order.
> > > + */
> > > + iowrite8(value >> 24, phy->iobase + addr + 3);
> > > + iowrite8(value >> 16, phy->iobase + addr + 2);
> > > + iowrite8(value >> 8, phy->iobase + addr + 1);
> > > + iowrite8(value, phy->iobase + addr);
> > > +
> > > + return 0;
> > > +}
> > > +
> > > +static const struct tpm_tis_phy_ops tpm_tcg_bw = {
> > > + .read_bytes = tpm_tis_synquacer_read_bytes,
> > > + .write_bytes = tpm_tis_synquacer_write_bytes,
> > > + .read16 = tpm_tis_synquacer_read16_bw,
> > > + .read32 = tpm_tis_synquacer_read32_bw,
> > > + .write32 = tpm_tis_synquacer_write32_bw,
> > > +};
> > > +
> > > +static int tpm_tis_synquacer_init(struct device *dev,
> > > + struct tpm_tis_synquacer_info *tpm_info)
> > > +{
> > > + struct tpm_tis_synquacer_phy *phy;
> > > +
> > > + phy = devm_kzalloc(dev, sizeof(struct tpm_tis_synquacer_phy), GFP_KERNEL);
> > > + if (phy == NULL)
> > > + return -ENOMEM;
> > > +
> > > + phy->iobase = devm_ioremap_resource(dev, &tpm_info->res);
> > > + if (IS_ERR(phy->iobase))
> > > + return PTR_ERR(phy->iobase);
> > > +
> > > + return tpm_tis_core_init(dev, &phy->priv, tpm_info->irq, &tpm_tcg_bw,
> > > + ACPI_HANDLE(dev));
> > > +}
> > > +
> > > +static SIMPLE_DEV_PM_OPS(tpm_tis_synquacer_pm, tpm_pm_suspend, tpm_tis_resume);
> > > +
> > > +static int tpm_tis_synquacer_probe(struct platform_device *pdev)
> > > +{
> > > + struct tpm_tis_synquacer_info tpm_info = {};
> > > + struct resource *res;
> > > +
> > > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > > + if (res == NULL) {
> > > + dev_err(&pdev->dev, "no memory resource defined\n");
> > > + return -ENODEV;
> > > + }
> > > + tpm_info.res = *res;
> > > +
> > > + tpm_info.irq = -1;
> > > +
> > > + return tpm_tis_synquacer_init(&pdev->dev, &tpm_info);
> > > +}
> > > +
> > > +static int tpm_tis_synquacer_remove(struct platform_device *pdev)
> > > +{
> > > + struct tpm_chip *chip = dev_get_drvdata(&pdev->dev);
> > > +
> > > + tpm_chip_unregister(chip);
> > > + tpm_tis_remove(chip);
> > > +
> > > + return 0;
> > > +}
> > > +
> > > +#ifdef CONFIG_OF
> > > +static const struct of_device_id tis_synquacer_of_platform_match[] = {
> > > + {.compatible = "socionext,synquacer-tpm-mmio"},
> > > + {},
> > > +};
> > > +MODULE_DEVICE_TABLE(of, tis_synquacer_of_platform_match);
> > > +#endif
> > > +
> > > +#ifdef CONFIG_ACPI
> > > +static const struct acpi_device_id tpm_synquacer_acpi_tbl[] = {
> > > + { "SCX0009" },
> > > + {},
> > > +};
> > > +MODULE_DEVICE_TABLE(acpi, tpm_synquacer_acpi_tbl);
> > > +#endif
> > > +
> > > +static struct platform_driver tis_synquacer_drv = {
> > > + .probe = tpm_tis_synquacer_probe,
> > > + .remove = tpm_tis_synquacer_remove,
> > > + .driver = {
> > > + .name = "tpm_tis_synquacer",
> > > + .pm = &tpm_tis_synquacer_pm,
> > > + .of_match_table = of_match_ptr(tis_synquacer_of_platform_match),
> > > + .acpi_match_table = ACPI_PTR(tpm_synquacer_acpi_tbl),
> > > + },
> > > +};
> > > +
> > > +static int __init tpm_tis_synquacer_module_init(void)
> > > +{
> > > + int rc;
> > > +
> > > + rc = platform_driver_register(&tis_synquacer_drv);
> > > + if (rc)
> > > + return rc;
> > > +
> > > + return 0;
> > > +}
> > > +
> > > +static void __exit tpm_tis_synquacer_module_exit(void)
> > > +{
> > > + platform_driver_unregister(&tis_synquacer_drv);
> > > +}
> > > +
> > > +module_init(tpm_tis_synquacer_module_init);
> > > +module_exit(tpm_tis_synquacer_module_exit);
> > > +MODULE_AUTHOR("Masahisa Kojima (masahisa.kojima@xxxxxxxxxx)");
> >
> > It is completely redundant field because authorship is part of the
> > commit object itself. And it does not tell the truth after a while
> > anyway. MODULE_AUTHOR() made more sense before there was any sort of
> > legit versio control in place.
> >
> > I think it would be better not to have it as we don't have any use
> > for this data. It is just cruft hanging there.
>
> OK, I will remove MODULE_AUTHOR() line.
> I will also plan to remove MODULE_VERSION("2.0").
> tpm_tis_spi_main.c only has MODULE_DESCRIPTION() and MODULE_LICENSE(),
> I plan to follow this example.
>
> Regards,
> Masahisa
Yeah, I mean in GIT log your authority will be already sealed :-)
/Jarkko
