diff options
Diffstat (limited to 'drivers/soc/tegra/pmc.c')
| -rw-r--r-- | drivers/soc/tegra/pmc.c | 100 |
1 files changed, 97 insertions, 3 deletions
diff --git a/drivers/soc/tegra/pmc.c b/drivers/soc/tegra/pmc.c index dba89fc81a04..0df258518693 100644 --- a/drivers/soc/tegra/pmc.c +++ b/drivers/soc/tegra/pmc.c @@ -20,6 +20,7 @@ #define pr_fmt(fmt) "tegra-pmc: " fmt +#include <linux/arm-smccc.h> #include <linux/clk.h> #include <linux/clk/tegra.h> #include <linux/debugfs.h> @@ -145,6 +146,11 @@ #define WAKE_AOWAKE_CTRL 0x4f4 #define WAKE_AOWAKE_CTRL_INTR_POLARITY BIT(0) +/* for secure PMC */ +#define TEGRA_SMC_PMC 0xc2fffe00 +#define TEGRA_SMC_PMC_READ 0xaa +#define TEGRA_SMC_PMC_WRITE 0xbb + struct tegra_powergate { struct generic_pm_domain genpd; struct tegra_pmc *pmc; @@ -216,6 +222,7 @@ struct tegra_pmc_soc { bool has_gpu_clamps; bool needs_mbist_war; bool has_impl_33v_pwr; + bool maybe_tz_only; const struct tegra_io_pad_soc *io_pads; unsigned int num_io_pads; @@ -278,6 +285,7 @@ static const char * const tegra30_reset_sources[] = { * @scratch: pointer to I/O remapped region for scratch registers * @clk: pointer to pclk clock * @soc: pointer to SoC data structure + * @tz_only: flag specifying if the PMC can only be accessed via TrustZone * @debugfs: pointer to debugfs entry * @rate: currently configured rate of pclk * @suspend_mode: lowest suspend mode available @@ -308,6 +316,7 @@ struct tegra_pmc { struct dentry *debugfs; const struct tegra_pmc_soc *soc; + bool tz_only; unsigned long rate; @@ -346,13 +355,62 @@ to_powergate(struct generic_pm_domain *domain) static u32 tegra_pmc_readl(struct tegra_pmc *pmc, unsigned long offset) { + struct arm_smccc_res res; + + if (pmc->tz_only) { + arm_smccc_smc(TEGRA_SMC_PMC, TEGRA_SMC_PMC_READ, offset, 0, 0, + 0, 0, 0, &res); + if (res.a0) { + if (pmc->dev) + dev_warn(pmc->dev, "%s(): SMC failed: %lu\n", + __func__, res.a0); + else + pr_warn("%s(): SMC failed: %lu\n", __func__, + res.a0); + } + + return res.a1; + } + return readl(pmc->base + offset); } static void tegra_pmc_writel(struct tegra_pmc *pmc, u32 value, unsigned long offset) { - writel(value, pmc->base + offset); + struct arm_smccc_res res; + + if (pmc->tz_only) { + arm_smccc_smc(TEGRA_SMC_PMC, TEGRA_SMC_PMC_WRITE, offset, + value, 0, 0, 0, 0, &res); + if (res.a0) { + if (pmc->dev) + dev_warn(pmc->dev, "%s(): SMC failed: %lu\n", + __func__, res.a0); + else + pr_warn("%s(): SMC failed: %lu\n", __func__, + res.a0); + } + } else { + writel(value, pmc->base + offset); + } +} + +static u32 tegra_pmc_scratch_readl(struct tegra_pmc *pmc, unsigned long offset) +{ + if (pmc->tz_only) + return tegra_pmc_readl(pmc, offset); + + return readl(pmc->scratch + offset); +} + +static void tegra_pmc_scratch_writel(struct tegra_pmc *pmc, u32 value, + unsigned long offset) +{ + if (pmc->tz_only) + tegra_pmc_writel(pmc, value, offset); + else + writel(value, pmc->scratch + offset); } /* @@ -776,7 +834,7 @@ static int tegra_pmc_restart_notify(struct notifier_block *this, const char *cmd = data; u32 value; - value = readl(pmc->scratch + pmc->soc->regs->scratch0); + value = tegra_pmc_scratch_readl(pmc, pmc->soc->regs->scratch0); value &= ~PMC_SCRATCH0_MODE_MASK; if (cmd) { @@ -790,7 +848,7 @@ static int tegra_pmc_restart_notify(struct notifier_block *this, value |= PMC_SCRATCH0_MODE_RCM; } - writel(value, pmc->scratch + pmc->soc->regs->scratch0); + tegra_pmc_scratch_writel(pmc, value, pmc->soc->regs->scratch0); /* reset everything but PMC_SCRATCH0 and PMC_RST_STATUS */ value = tegra_pmc_readl(pmc, PMC_CNTRL); @@ -2071,6 +2129,7 @@ static const struct tegra_pmc_soc tegra20_pmc_soc = { .has_gpu_clamps = false, .needs_mbist_war = false, .has_impl_33v_pwr = false, + .maybe_tz_only = false, .num_io_pads = 0, .io_pads = NULL, .num_pin_descs = 0, @@ -2117,6 +2176,7 @@ static const struct tegra_pmc_soc tegra30_pmc_soc = { .has_gpu_clamps = false, .needs_mbist_war = false, .has_impl_33v_pwr = false, + .maybe_tz_only = false, .num_io_pads = 0, .io_pads = NULL, .num_pin_descs = 0, @@ -2167,6 +2227,7 @@ static const struct tegra_pmc_soc tegra114_pmc_soc = { .has_gpu_clamps = false, .needs_mbist_war = false, .has_impl_33v_pwr = false, + .maybe_tz_only = false, .num_io_pads = 0, .io_pads = NULL, .num_pin_descs = 0, @@ -2277,6 +2338,7 @@ static const struct tegra_pmc_soc tegra124_pmc_soc = { .has_gpu_clamps = true, .needs_mbist_war = false, .has_impl_33v_pwr = false, + .maybe_tz_only = false, .num_io_pads = ARRAY_SIZE(tegra124_io_pads), .io_pads = tegra124_io_pads, .num_pin_descs = ARRAY_SIZE(tegra124_pin_descs), @@ -2382,6 +2444,7 @@ static const struct tegra_pmc_soc tegra210_pmc_soc = { .has_gpu_clamps = true, .needs_mbist_war = true, .has_impl_33v_pwr = false, + .maybe_tz_only = true, .num_io_pads = ARRAY_SIZE(tegra210_io_pads), .io_pads = tegra210_io_pads, .num_pin_descs = ARRAY_SIZE(tegra210_pin_descs), @@ -2506,6 +2569,7 @@ static const struct tegra_pmc_soc tegra186_pmc_soc = { .has_gpu_clamps = false, .needs_mbist_war = false, .has_impl_33v_pwr = true, + .maybe_tz_only = false, .num_io_pads = ARRAY_SIZE(tegra186_io_pads), .io_pads = tegra186_io_pads, .num_pin_descs = ARRAY_SIZE(tegra186_pin_descs), @@ -2585,6 +2649,7 @@ static const struct tegra_pmc_soc tegra194_pmc_soc = { .has_gpu_clamps = false, .needs_mbist_war = false, .has_impl_33v_pwr = false, + .maybe_tz_only = false, .num_io_pads = ARRAY_SIZE(tegra194_io_pads), .io_pads = tegra194_io_pads, .regs = &tegra186_pmc_regs, @@ -2619,6 +2684,32 @@ static struct platform_driver tegra_pmc_driver = { }; builtin_platform_driver(tegra_pmc_driver); +static bool __init tegra_pmc_detect_tz_only(struct tegra_pmc *pmc) +{ + u32 value, saved; + + saved = readl(pmc->base + pmc->soc->regs->scratch0); + value = saved ^ 0xffffffff; + + if (value == 0xffffffff) + value = 0xdeadbeef; + + /* write pattern and read it back */ + writel(value, pmc->base + pmc->soc->regs->scratch0); + value = readl(pmc->base + pmc->soc->regs->scratch0); + + /* if we read all-zeroes, access is restricted to TZ only */ + if (value == 0) { + pr_info("access to PMC is restricted to TZ\n"); + return true; + } + + /* restore original value */ + writel(saved, pmc->base + pmc->soc->regs->scratch0); + + return false; +} + /* * Early initialization to allow access to registers in the very early boot * process. @@ -2681,6 +2772,9 @@ static int __init tegra_pmc_early_init(void) if (np) { pmc->soc = match->data; + if (pmc->soc->maybe_tz_only) + pmc->tz_only = tegra_pmc_detect_tz_only(pmc); + tegra_powergate_init(pmc, np); /* |