Re: [PATCH V6 1/3] platform/x86: Add Intel Software Defined Silicon driver

From: Joe Perches
Date: Mon Feb 07 2022 - 20:50:45 EST


On Mon, 2022-02-07 at 16:54 -0800, David E. Box wrote:
> Intel Software Defined Silicon (SDSi) is a post manufacturing mechanism for
> activating additional silicon features. Features are enabled through a
> license activation process. The SDSi driver provides a per socket, sysfs
> attribute interface for applications to perform 3 main provisioning
> functions:
[]
> ---
> V6
> - Replace,
> return (ret < 0) ? ret : size;
> with,
> if (ret)
> return ret;
> return size
>
> Besides the style change (suggested by GKH) this fixes a klocwork
> warning.

thanks.

> diff --git a/drivers/platform/x86/intel/sdsi.c b/drivers/platform/x86/intel/sdsi.c

[]

> +/* SDSi mailbox operations must be performed using 64bit mov instructions */
> +static __always_inline void
> +sdsi_memcpy64_toio(u64 __iomem *to, const u64 *from, size_t count_bytes)
> +{
> + size_t count = count_bytes / sizeof(*to);
> + int i;
> +
> + for (i = 0; i < count; i++)
> + writeq(from[i], &to[i]);

Any chance the byte count is not a multiple of sizeof(u64) ?

> +static __always_inline void
> +sdsi_memcpy64_fromio(u64 *to, const u64 __iomem *from, size_t count_bytes)
> +{
> + size_t count = count_bytes / sizeof(*to);
> + int i;
> +
> + for (i = 0; i < count; i++)
> + to[i] = readq(&from[i]);
> +}

here too.

[]

> +static int sdsi_mbox_cmd_read(struct sdsi_priv *priv, struct sdsi_mbox_info *info,
> + size_t *data_size)
> +{
> + struct device *dev = priv->dev;
> + u32 total, loop, eom, status, message_size;
[]
> + if (packet_size > SDSI_SIZE_MAILBOX) {
> + dev_err(dev, "Packet size to large\n");

too

[]
> + /* Message size check is only valid for multi-packet transfers */
> + if (loop && total != message_size)
> + dev_warn(dev, "Read count %d differs from expected count %d\n",

%u

> + total, message_size);


> +static int sdsi_map_mbox_registers(struct sdsi_priv *priv, struct pci_dev *parent,
> + struct disc_table *disc_table, struct resource *disc_res)
> +{
> + u32 access_type = FIELD_GET(DT_ACCESS_TYPE, disc_table->access_info);
> + u32 size = FIELD_GET(DT_SIZE, disc_table->access_info);
> + u32 tbir = FIELD_GET(DT_TBIR, disc_table->offset);
> + u32 offset = DT_OFFSET(disc_table->offset);
> + u32 features_offset;
> + struct resource res = {};
> +
> + /* Starting location of SDSi MMIO region based on access type */
> + switch (access_type) {
> + case ACCESS_TYPE_LOCAL:
> + if (tbir) {
> + dev_err(priv->dev, "Unsupported BAR index %d for access type %d\n",
> + tbir, access_type);

%u here too

[]
> + dev_err(priv->dev, "Unrecognized access_type %d\n", access_type);

and here