Re: [PATCH v1 6/8] crypto: ccp - Add vdata for platform device

Tom Lendacky
2023-01-31T20:36:15Z

On 1/23/23 09:22, Jeremi Piotrowski wrote:
> When matching the "psp" platform_device, determine the register offsets
> at runtime from the ASP ACPI table. Pass the parsed register offsets
> from the ASPT through platdata.
>
> To support this scenario, mark the members of 'struct sev_vdata' and
> 'struct psp_vdata' non-const so that the probe function can write the
> values. This does not affect the other users of sev_vdata/psp_vdata as
> they define the whole struct const and the pointer in struct
> sp_dev_vdata stays const too.
>
> Signed-off-by: Jeremi Piotrowski <jpiotrowski@linux.microsoft.com>
> ---
> arch/x86/kernel/psp.c | 3 ++
> drivers/crypto/ccp/sp-dev.h | 12 +++----
> drivers/crypto/ccp/sp-platform.c | 57 +++++++++++++++++++++++++++++++-
> 3 files changed, 65 insertions(+), 7 deletions(-)
>
> diff --git a/arch/x86/kernel/psp.c b/arch/x86/kernel/psp.c
> index 24181d132bae..68511a14df63 100644
> --- a/arch/x86/kernel/psp.c
> +++ b/arch/x86/kernel/psp.c
> @@ -199,6 +199,9 @@ static int __init psp_init_platform_device(void)
> if (err)
> return err;
> err = platform_device_add_resources(&psp_device, res, 2);
> + if (err)
> + return err;
> + err = platform_device_add_data(&psp_device, &pdata, sizeof(pdata));
> if (err)
> return err;
>
> diff --git a/drivers/crypto/ccp/sp-dev.h b/drivers/crypto/ccp/sp-dev.h
> index 20377e67f65d..aaa651364425 100644
> --- a/drivers/crypto/ccp/sp-dev.h
> +++ b/drivers/crypto/ccp/sp-dev.h
> @@ -40,9 +40,9 @@ struct ccp_vdata {
> };
>
> struct sev_vdata {
> - const unsigned int cmdresp_reg;
> - const unsigned int cmdbuff_addr_lo_reg;
> - const unsigned int cmdbuff_addr_hi_reg;
> + unsigned int cmdresp_reg;
> + unsigned int cmdbuff_addr_lo_reg;
> + unsigned int cmdbuff_addr_hi_reg;
> };
>
> struct tee_vdata {
> @@ -56,9 +56,9 @@ struct tee_vdata {
> struct psp_vdata {
> const struct sev_vdata *sev;
> const struct tee_vdata *tee;
> - const unsigned int feature_reg;
> - const unsigned int inten_reg;
> - const unsigned int intsts_reg;
> + unsigned int feature_reg;
> + unsigned int inten_reg;
> + unsigned int intsts_reg;
> };
>
> /* Structure to hold SP device data */
> diff --git a/drivers/crypto/ccp/sp-platform.c b/drivers/crypto/ccp/sp-platform.c
> index ea8926e87981..281dbf6b150c 100644
> --- a/drivers/crypto/ccp/sp-platform.c
> +++ b/drivers/crypto/ccp/sp-platform.c
> @@ -22,6 +22,7 @@
> #include <linux/of.h>
> #include <linux/of_address.h>
> #include <linux/acpi.h>
> +#include <linux/platform_data/psp.h>
>
> #include "ccp-dev.h"
>
> @@ -30,11 +31,31 @@ struct sp_platform {
> unsigned int irq_count;
> };
>
> +#ifdef CONFIG_CRYPTO_DEV_SP_PSP
> +static struct sev_vdata sev_platform = {
> + .cmdresp_reg = -1,
> + .cmdbuff_addr_lo_reg = -1,
> + .cmdbuff_addr_hi_reg = -1,
> +};
> +static struct psp_vdata psp_platform = {
> + .sev = &sev_platform,
> + .feature_reg = -1,
> + .inten_reg = -1,
> + .intsts_reg = -1,
> +};
> +#endif
> +
> static const struct sp_dev_vdata dev_vdata[] = {
> {
> .bar = 0,
> #ifdef CONFIG_CRYPTO_DEV_SP_CCP
> .ccp_vdata = &ccpv3_platform,
> +#endif
> + },
> + {
> + .bar = 0,
> +#ifdef CONFIG_CRYPTO_DEV_SP_PSP
> + .psp_vdata = &psp_platform,
> #endif
> },
> };
> @@ -57,7 +78,7 @@ MODULE_DEVICE_TABLE(of, sp_of_match);
> #endif
>
> static const struct platform_device_id sp_plat_match[] = {
> - { "psp" },
> + { "psp", (kernel_ulong_t)&dev_vdata[1] },
> { },
> };
> MODULE_DEVICE_TABLE(platform, sp_plat_match);
> @@ -86,6 +107,38 @@ static struct sp_dev_vdata *sp_get_acpi_version(struct platform_device *pdev)
> return NULL;
> }
>
> +static struct sp_dev_vdata *sp_get_plat_version(struct platform_device *pdev)
> +{
> + struct sp_dev_vdata *drvdata = (struct sp_dev_vdata *)pdev->id_entry->driver_data;

s/drvdata/vdata/

> + struct device *dev = &pdev->dev;
> +

Should check for null vdata and return NULL, e.g.:

if (!vdata)
return NULL;

> + if (drvdata == &dev_vdata[1]) {

This should be a check for vdata->psp_vdata being non-NULL and
vdata->psp_vdata->sev being non-NULL, e.g.:

if (vdata->psp_vdata && vdata->psp_vdata->sev) {

> + struct psp_platform_data *pdata = dev_get_platdata(dev);
> +
> + if (!pdata) {
> + dev_err(dev, "missing platform data\n");
> + return NULL;
> + }
> +#ifdef CONFIG_CRYPTO_DEV_SP_PSP

No need for this with the above checks

> + psp_platform.feature_reg = pdata->feature_reg;

These should then be:

vdata->psp_vdata->inten_reg = pdata->feature_reg;
...

> + psp_platform.inten_reg = pdata->irq_en_reg;
> + psp_platform.intsts_reg = pdata->irq_st_reg;
> + sev_platform.cmdresp_reg = pdata->sev_cmd_resp_reg;

And this should be:

vdata->psp_vdata->sev->cmdbuff_addr_lo = ...

> + sev_platform.cmdbuff_addr_lo_reg = pdata->sev_cmd_buf_lo_reg;
> + sev_platform.cmdbuff_addr_hi_reg = pdata->sev_cmd_buf_hi_reg;
> + dev_dbg(dev, "GLBL feature:\t%x\n", pdata->feature_reg);

s/GLBL feature/PSP feature register/

> + dev_dbg(dev, "GLBL irq en:\t%x\n", pdata->irq_en_reg);

s/GLBL irq en/PSP IRQ enable register/

> + dev_dbg(dev, "GLBL irq st:\t%x\n", pdata->irq_st_reg);

s/GLBL irq st/PSP IRQ status register/

> + dev_dbg(dev, "SEV cmdresp:\t%x\n", pdata->sev_cmd_resp_reg);

s/SEV cmdresp/SEV cmdresp register/

> + dev_dbg(dev, "SEV cmdbuf lo:\t%x\n", pdata->sev_cmd_buf_lo_reg);

s/SEV cmdbuf lo/SEV cmdbuf lo register/

> + dev_dbg(dev, "SEV cmdbuf hi:\t%x\n", pdata->sev_cmd_buf_hi_reg);

s/SEV cmdbuf hi/SEV cmdbuf hi register/

> + dev_dbg(dev, "SEV mbox:\t%x\n", pdata->mbox_irq_id);

s/SEV mbox/SEV cmdresp IRQ/

> + dev_dbg(dev, "ACPI cmdresp:\t%x\n", pdata->acpi_cmd_resp_reg);

Duplicate entry

> +#endif
> + }
> + return drvdata;
> +}
> +
> static int sp_get_irqs(struct sp_device *sp)
> {
> struct sp_platform *sp_platform = sp->dev_specific;
> @@ -137,6 +190,8 @@ static int sp_platform_probe(struct platform_device *pdev)
> sp->dev_specific = sp_platform;
> sp->dev_vdata = pdev->dev.of_node ? sp_get_of_version(pdev)
> : sp_get_acpi_version(pdev);
> + if (!sp->dev_vdata && pdev->id_entry)

Move this pdev->id_entry check into sp_get_plat_version(), returning NULL
if not set.

Thanks,
Tom

> + sp->dev_vdata = sp_get_plat_version(pdev);
> if (!sp->dev_vdata) {
> ret = -ENODEV;
> dev_err(dev, "missing driver data\n");