diff options
Diffstat (limited to 'drivers/crypto/ccp/psp-dev.c')
| -rw-r--r-- | drivers/crypto/ccp/psp-dev.c | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/drivers/crypto/ccp/psp-dev.c b/drivers/crypto/ccp/psp-dev.c index d42d7bc62352..3258c4612e14 100644 --- a/drivers/crypto/ccp/psp-dev.c +++ b/drivers/crypto/ccp/psp-dev.c @@ -9,6 +9,9 @@ #include <linux/kernel.h> #include <linux/irqreturn.h> +#include <linux/mutex.h> +#include <linux/bitfield.h> +#include <linux/delay.h> #include "sp-dev.h" #include "psp-dev.h" @@ -19,6 +22,62 @@ struct psp_device *psp_master; +#define PSP_C2PMSG_17_CMDRESP_CMD GENMASK(19, 16) + +static int psp_mailbox_poll(const void __iomem *cmdresp_reg, unsigned int *cmdresp, + unsigned int timeout_msecs) +{ + while (true) { + *cmdresp = ioread32(cmdresp_reg); + if (FIELD_GET(PSP_CMDRESP_RESP, *cmdresp)) + return 0; + + if (!timeout_msecs--) + break; + + usleep_range(1000, 1100); + } + + return -ETIMEDOUT; +} + +int psp_mailbox_command(struct psp_device *psp, enum psp_cmd cmd, void *cmdbuff, + unsigned int timeout_msecs, unsigned int *cmdresp) +{ + void __iomem *cmdresp_reg, *cmdbuff_lo_reg, *cmdbuff_hi_reg; + int ret; + + if (!psp || !psp->vdata || !psp->vdata->cmdresp_reg || + !psp->vdata->cmdbuff_addr_lo_reg || !psp->vdata->cmdbuff_addr_hi_reg) + return -ENODEV; + + cmdresp_reg = psp->io_regs + psp->vdata->cmdresp_reg; + cmdbuff_lo_reg = psp->io_regs + psp->vdata->cmdbuff_addr_lo_reg; + cmdbuff_hi_reg = psp->io_regs + psp->vdata->cmdbuff_addr_hi_reg; + + mutex_lock(&psp->mailbox_mutex); + + /* Ensure mailbox is ready for a command */ + ret = -EBUSY; + if (psp_mailbox_poll(cmdresp_reg, cmdresp, 0)) + goto unlock; + + if (cmdbuff) { + iowrite32(lower_32_bits(__psp_pa(cmdbuff)), cmdbuff_lo_reg); + iowrite32(upper_32_bits(__psp_pa(cmdbuff)), cmdbuff_hi_reg); + } + + *cmdresp = FIELD_PREP(PSP_C2PMSG_17_CMDRESP_CMD, cmd); + iowrite32(*cmdresp, cmdresp_reg); + + ret = psp_mailbox_poll(cmdresp_reg, cmdresp, timeout_msecs); + +unlock: + mutex_unlock(&psp->mailbox_mutex); + + return ret; +} + static struct psp_device *psp_alloc_struct(struct sp_device *sp) { struct device *dev = sp->dev; @@ -164,6 +223,7 @@ int psp_dev_init(struct sp_device *sp) } psp->io_regs = sp->io_map; + mutex_init(&psp->mailbox_mutex); ret = psp_get_capability(psp); if (ret) |