diff options
Diffstat (limited to 'target/linux/bcm27xx/patches-5.4/950-0204-hwrng-iproc-rng200-Add-BCM2838-support.patch')
| -rw-r--r-- | target/linux/bcm27xx/patches-5.4/950-0204-hwrng-iproc-rng200-Add-BCM2838-support.patch | 158 |
1 files changed, 158 insertions, 0 deletions
diff --git a/target/linux/bcm27xx/patches-5.4/950-0204-hwrng-iproc-rng200-Add-BCM2838-support.patch b/target/linux/bcm27xx/patches-5.4/950-0204-hwrng-iproc-rng200-Add-BCM2838-support.patch new file mode 100644 index 0000000000..c9eac88066 --- /dev/null +++ b/target/linux/bcm27xx/patches-5.4/950-0204-hwrng-iproc-rng200-Add-BCM2838-support.patch @@ -0,0 +1,158 @@ +From cbf5cde9c460eae458829a7b357cea6734c4755b Mon Sep 17 00:00:00 2001 +From: Stefan Wahren <wahrenst@gmx.net> +Date: Sat, 4 May 2019 17:06:15 +0200 +Subject: [PATCH] hwrng: iproc-rng200: Add BCM2838 support + +The HWRNG on the BCM2838 is compatible to iproc-rng200, so add the +support to this driver instead of bcm2835-rng. + +Signed-off-by: Stefan Wahren <wahrenst@gmx.net> +--- + drivers/char/hw_random/Kconfig | 4 +- + drivers/char/hw_random/iproc-rng200.c | 81 +++++++++++++++++++++++++-- + 2 files changed, 79 insertions(+), 6 deletions(-) + +--- a/drivers/char/hw_random/Kconfig ++++ b/drivers/char/hw_random/Kconfig +@@ -90,11 +90,11 @@ config HW_RANDOM_BCM2835 + + config HW_RANDOM_IPROC_RNG200 + tristate "Broadcom iProc/STB RNG200 support" +- depends on ARCH_BCM_IPROC || ARCH_BRCMSTB ++ depends on ARCH_BCM_IPROC || ARCH_BCM2835 || ARCH_BRCMSTB + default HW_RANDOM + ---help--- + This driver provides kernel-side support for the RNG200 +- hardware found on the Broadcom iProc and STB SoCs. ++ hardware found on the Broadcom iProc, BCM2838 and STB SoCs. + + To compile this driver as a module, choose M here: the + module will be called iproc-rng200 +--- a/drivers/char/hw_random/iproc-rng200.c ++++ b/drivers/char/hw_random/iproc-rng200.c +@@ -29,6 +29,7 @@ + #define RNG_CTRL_RNG_RBGEN_MASK 0x00001FFF + #define RNG_CTRL_RNG_RBGEN_ENABLE 0x00000001 + #define RNG_CTRL_RNG_RBGEN_DISABLE 0x00000000 ++#define RNG_CTRL_RNG_DIV_CTRL_SHIFT 13 + + #define RNG_SOFT_RESET_OFFSET 0x04 + #define RNG_SOFT_RESET 0x00000001 +@@ -36,16 +37,23 @@ + #define RBG_SOFT_RESET_OFFSET 0x08 + #define RBG_SOFT_RESET 0x00000001 + ++#define RNG_TOTAL_BIT_COUNT_OFFSET 0x0C ++ ++#define RNG_TOTAL_BIT_COUNT_THRESHOLD_OFFSET 0x10 ++ + #define RNG_INT_STATUS_OFFSET 0x18 + #define RNG_INT_STATUS_MASTER_FAIL_LOCKOUT_IRQ_MASK 0x80000000 + #define RNG_INT_STATUS_STARTUP_TRANSITIONS_MET_IRQ_MASK 0x00020000 + #define RNG_INT_STATUS_NIST_FAIL_IRQ_MASK 0x00000020 + #define RNG_INT_STATUS_TOTAL_BITS_COUNT_IRQ_MASK 0x00000001 + ++#define RNG_INT_ENABLE_OFFSET 0x1C ++ + #define RNG_FIFO_DATA_OFFSET 0x20 + + #define RNG_FIFO_COUNT_OFFSET 0x24 + #define RNG_FIFO_COUNT_RNG_FIFO_COUNT_MASK 0x000000FF ++#define RNG_FIFO_COUNT_RNG_FIFO_THRESHOLD_SHIFT 8 + + struct iproc_rng200_dev { + struct hwrng rng; +@@ -166,6 +174,64 @@ static int iproc_rng200_init(struct hwrn + return 0; + } + ++static int bcm2838_rng200_read(struct hwrng *rng, void *buf, size_t max, ++ bool wait) ++{ ++ struct iproc_rng200_dev *priv = to_rng_priv(rng); ++ u32 max_words = max / sizeof(u32); ++ u32 num_words, count, val; ++ ++ /* ensure warm up period has elapsed */ ++ while (1) { ++ val = ioread32(priv->base + RNG_TOTAL_BIT_COUNT_OFFSET); ++ if (val > 16) ++ break; ++ cpu_relax(); ++ } ++ ++ /* ensure fifo is not empty */ ++ while (1) { ++ num_words = ioread32(priv->base + RNG_FIFO_COUNT_OFFSET) & ++ RNG_FIFO_COUNT_RNG_FIFO_COUNT_MASK; ++ if (num_words) ++ break; ++ if (!wait) ++ return 0; ++ cpu_relax(); ++ } ++ ++ if (num_words > max_words) ++ num_words = max_words; ++ ++ for (count = 0; count < num_words; count++) { ++ ((u32 *)buf)[count] = ioread32(priv->base + ++ RNG_FIFO_DATA_OFFSET); ++ } ++ ++ return num_words * sizeof(u32); ++} ++ ++static int bcm2838_rng200_init(struct hwrng *rng) ++{ ++ struct iproc_rng200_dev *priv = to_rng_priv(rng); ++ uint32_t val; ++ ++ if (ioread32(priv->base + RNG_CTRL_OFFSET) & RNG_CTRL_RNG_RBGEN_MASK) ++ return 0; ++ ++ /* initial numbers generated are "less random" so will be discarded */ ++ val = 0x40000; ++ iowrite32(val, priv->base + RNG_TOTAL_BIT_COUNT_THRESHOLD_OFFSET); ++ /* min fifo count to generate full interrupt */ ++ val = 2 << RNG_FIFO_COUNT_RNG_FIFO_THRESHOLD_SHIFT; ++ iowrite32(val, priv->base + RNG_FIFO_COUNT_OFFSET); ++ /* enable the rng - 1Mhz sample rate */ ++ val = (0x3 << RNG_CTRL_RNG_DIV_CTRL_SHIFT) | RNG_CTRL_RNG_RBGEN_MASK; ++ iowrite32(val, priv->base + RNG_CTRL_OFFSET); ++ ++ return 0; ++} ++ + static void iproc_rng200_cleanup(struct hwrng *rng) + { + struct iproc_rng200_dev *priv = to_rng_priv(rng); +@@ -202,10 +268,16 @@ static int iproc_rng200_probe(struct pla + return PTR_ERR(priv->base); + } + +- priv->rng.name = "iproc-rng200", +- priv->rng.read = iproc_rng200_read, +- priv->rng.init = iproc_rng200_init, +- priv->rng.cleanup = iproc_rng200_cleanup, ++ priv->rng.name = pdev->name; ++ priv->rng.cleanup = iproc_rng200_cleanup; ++ ++ if (of_device_is_compatible(dev->of_node, "brcm,bcm2838-rng200")) { ++ priv->rng.init = bcm2838_rng200_init; ++ priv->rng.read = bcm2838_rng200_read; ++ } else { ++ priv->rng.init = iproc_rng200_init; ++ priv->rng.read = iproc_rng200_read; ++ } + + /* Register driver */ + ret = devm_hwrng_register(dev, &priv->rng); +@@ -223,6 +295,7 @@ static const struct of_device_id iproc_r + { .compatible = "brcm,bcm7211-rng200", }, + { .compatible = "brcm,bcm7278-rng200", }, + { .compatible = "brcm,iproc-rng200", }, ++ { .compatible = "brcm,bcm2838-rng200"}, + {}, + }; + MODULE_DEVICE_TABLE(of, iproc_rng200_of_match); |