kernel/drivers/crypto/ccp/psp-dev.c, branch linux-6.9.y

crypto: ccp - State in dmesg that TSME is enabled

2024-02-17T01:09:16Z

In the case when only TSME is enabled, it is useful to state that fact too, so that users are aware that memory encryption is still enabled even when the corresponding software variant of memory encryption is not enabled. Signed-off-by: Borislav Petkov (AMD) Acked-by: Tom Lendacky Signed-off-by: Herbert Xu

crypto: ccp - Add support for DBC over PSP mailbox

2023-09-15T10:29:46Z

On some SOCs DBC is supported through the PSP mailbox instead of the platform mailbox. This capability is advertised in the PSP capabilities register. Allow using this communication path if supported. Signed-off-by: Mario Limonciello Signed-off-by: Herbert Xu

crypto: ccp - Add a macro to check capabilities register

2023-09-15T10:29:46Z

Offsets are checked by the capabilities register in multiple places. To make the code more readable add a macro. Signed-off-by: Mario Limonciello Signed-off-by: Herbert Xu

crypto: ccp - Add support for extended PSP mailbox commands

2023-09-15T10:29:45Z

The PSP mailbox supports a number of extended sub-commands. These subcommands are placed in the header of the buffer sent to the mailbox. Signed-off-by: Mario Limonciello Signed-off-by: Herbert Xu

crypto: ccp - Move direct access to some PSP registers out of TEE

2023-09-15T10:29:45Z

With the PSP mailbox registers supporting more than just TEE, access to them must be maintained and serialized by the PSP device support. Remove TEE support direct access and create an interface in the PSP support where the register access can be controlled/serialized. Signed-off-by: Tom Lendacky Signed-off-by: Mario Limonciello Reviewed-by: Rijo Thomas Tested-by: Rijo Thomas Signed-off-by: Herbert Xu

crypto: ccp - Add support for fetching a nonce for dynamic boost control

2023-07-20T10:14:21Z

Dynamic Boost Control is a feature offered on AMD client platforms that allows software to request and set power or frequency limits. Only software that has authenticated with the PSP can retrieve or set these limits. Create a character device and ioctl for fetching the nonce. This ioctl supports optionally passing authentication information which will influence how many calls the nonce is valid for. Acked-by: Tom Lendacky Signed-off-by: Mario Limonciello Signed-off-by: Herbert Xu

crypto: ccp - move setting PSP master to earlier in the init

2023-07-20T10:13:16Z

Dynamic boost control needs to use platform access symbols that look for the PSP master as part of initialization. So move the PSP master before psp_init() so that dynamic boost control can be initialized properly. Acked-by: Tom Lendacky Signed-off-by: Mario Limonciello Signed-off-by: Herbert Xu

crypto: ccp - Clear PSP interrupt status register before calling handler

2023-04-06T08:19:45Z

The PSP IRQ is edge-triggered (MSI or MSI-X) in all cases supported by the psp module so clear the interrupt status register early in the handler to prevent missed interrupts. sev_irq_handler() calls wake_up() on a wait queue, which can result in a new command being submitted from a different CPU. This then races with the clearing of isr and can result in missed interrupts. A missed interrupt results in a command waiting until it times out, which results in the psp being declared dead. This is unlikely on bare metal, but has been observed when running virtualized. In the cases where this is observed, sev->cmdresp_reg has PSP_CMDRESP_RESP set which indicates that the command was processed correctly but no interrupt was asserted. The full sequence of events looks like this: CPU 1: submits SEV cmd #1 CPU 1: calls wait_event_timeout() CPU 0: enters psp_irq_handler() CPU 0: calls sev_handler()->wake_up() CPU 1: wakes up; finishes processing cmd #1 CPU 1: submits SEV cmd #2 CPU 1: calls wait_event_timeout() PSP: finishes processing cmd #2; interrupt status is still set; no interrupt CPU 0: clears intsts CPU 0: exits psp_irq_handler() CPU 1: wait_event_timeout() times out; psp_dead=true Fixes: 200664d5237f ("crypto: ccp: Add Secure Encrypted Virtualization (SEV) command support") Cc: stable@vger.kernel.org Signed-off-by: Jeremi Piotrowski Acked-by: Tom Lendacky Signed-off-by: Herbert Xu

crypto: ccp - Add support for an interface for platform features

2023-03-17T03:16:43Z

Some platforms with a PSP support an interface for features that interact directly with the PSP instead of through a SEV or TEE environment. Initialize this interface so that other drivers can consume it. These drivers may either be subdrivers for the ccp module or external modules. For external modules, export a symbol for them to utilize. Acked-by: Tom Lendacky Signed-off-by: Mario Limonciello Signed-off-by: Herbert Xu

crypto: ccp - Drop TEE support for IRQ handler

2023-03-17T03:16:43Z

The only PSP mailbox that currently supports interrupt on completion is the SEV mailbox. Drop the dead code for the TEE subdriver to potentially call it. Acked-by: Rijo Thomas Acked-by: Tom Lendacky Signed-off-by: Mario Limonciello Signed-off-by: Herbert Xu