X-Git-Url: https://git.karo-electronics.de/?a=blobdiff_plain;f=drivers%2Fcrypto%2Fcaam%2Fctrl.c;h=5e7c7614c8fc1781301caa111a6d53dfd80159fd;hb=90605becc7c6db45a84bb2d2a364db6e008f2a6e;hp=b010d42a18035fa48a8797dc802267f70db531d2;hpb=d8524ae9d6f492a9c6db9f4d89c5f9b8782fa2d5;p=karo-tx-linux.git diff --git a/drivers/crypto/caam/ctrl.c b/drivers/crypto/caam/ctrl.c index b010d42a1803..5e7c7614c8fc 100644 --- a/drivers/crypto/caam/ctrl.c +++ b/drivers/crypto/caam/ctrl.c @@ -5,6 +5,9 @@ * Copyright 2008-2012 Freescale Semiconductor, Inc. */ +#include +#include + #include "compat.h" #include "regs.h" #include "intern.h" @@ -13,82 +16,75 @@ #include "error.h" #include "ctrl.h" -static int caam_remove(struct platform_device *pdev) -{ - struct device *ctrldev; - struct caam_drv_private *ctrlpriv; - struct caam_drv_private_jr *jrpriv; - struct caam_full __iomem *topregs; - int ring, ret = 0; - - ctrldev = &pdev->dev; - ctrlpriv = dev_get_drvdata(ctrldev); - topregs = (struct caam_full __iomem *)ctrlpriv->ctrl; - - /* shut down JobRs */ - for (ring = 0; ring < ctrlpriv->total_jobrs; ring++) { - ret |= caam_jr_shutdown(ctrlpriv->jrdev[ring]); - jrpriv = dev_get_drvdata(ctrlpriv->jrdev[ring]); - irq_dispose_mapping(jrpriv->irq); - } - - /* Shut down debug views */ -#ifdef CONFIG_DEBUG_FS - debugfs_remove_recursive(ctrlpriv->dfs_root); -#endif - - /* Unmap controller region */ - iounmap(&topregs->ctrl); - - kfree(ctrlpriv->jrdev); - kfree(ctrlpriv); - - return ret; -} - /* * Descriptor to instantiate RNG State Handle 0 in normal mode and * load the JDKEK, TDKEK and TDSK registers */ -static void build_instantiation_desc(u32 *desc) +static void build_instantiation_desc(u32 *desc, int handle, int do_sk) { - u32 *jump_cmd; + u32 *jump_cmd, op_flags; init_job_desc(desc, 0); + op_flags = OP_TYPE_CLASS1_ALG | OP_ALG_ALGSEL_RNG | + (handle << OP_ALG_AAI_SHIFT) | OP_ALG_AS_INIT; + /* INIT RNG in non-test mode */ - append_operation(desc, OP_TYPE_CLASS1_ALG | OP_ALG_ALGSEL_RNG | - OP_ALG_AS_INIT); + append_operation(desc, op_flags); + + if (!handle && do_sk) { + /* + * For SH0, Secure Keys must be generated as well + */ + + /* wait for done */ + jump_cmd = append_jump(desc, JUMP_CLASS_CLASS1); + set_jump_tgt_here(desc, jump_cmd); + + /* + * load 1 to clear written reg: + * resets the done interrrupt and returns the RNG to idle. + */ + append_load_imm_u32(desc, 1, LDST_SRCDST_WORD_CLRW); + + /* Initialize State Handle */ + append_operation(desc, OP_TYPE_CLASS1_ALG | OP_ALG_ALGSEL_RNG | + OP_ALG_AAI_RNG4_SK); + } - /* wait for done */ - jump_cmd = append_jump(desc, JUMP_CLASS_CLASS1); - set_jump_tgt_here(desc, jump_cmd); + append_jump(desc, JUMP_CLASS_CLASS1 | JUMP_TYPE_HALT); +} - /* - * load 1 to clear written reg: - * resets the done interrupt and returns the RNG to idle. - */ - append_load_imm_u32(desc, 1, LDST_SRCDST_WORD_CLRW); +/* Descriptor for deinstantiation of State Handle 0 of the RNG block. */ +static void build_deinstantiation_desc(u32 *desc, int handle) +{ + init_job_desc(desc, 0); - /* generate secure keys (non-test) */ + /* Uninstantiate State Handle 0 */ append_operation(desc, OP_TYPE_CLASS1_ALG | OP_ALG_ALGSEL_RNG | - OP_ALG_RNG4_SK); + (handle << OP_ALG_AAI_SHIFT) | OP_ALG_AS_INITFINAL); + + append_jump(desc, JUMP_CLASS_CLASS1 | JUMP_TYPE_HALT); } -static int instantiate_rng(struct device *ctrldev) +/* + * run_descriptor_deco0 - runs a descriptor on DECO0, under direct control of + * the software (no JR/QI used). + * @ctrldev - pointer to device + * @status - descriptor status, after being run + * + * Return: - 0 if no error occurred + * - -ENODEV if the DECO couldn't be acquired + * - -EAGAIN if an error occurred while executing the descriptor + */ +static inline int run_descriptor_deco0(struct device *ctrldev, u32 *desc, + u32 *status) { struct caam_drv_private *ctrlpriv = dev_get_drvdata(ctrldev); struct caam_full __iomem *topregs; unsigned int timeout = 100000; - u32 *desc; - int i, ret = 0; - - desc = kmalloc(CAAM_CMD_SZ * 6, GFP_KERNEL | GFP_DMA); - if (!desc) { - dev_err(ctrldev, "can't allocate RNG init descriptor memory\n"); - return -ENOMEM; - } - build_instantiation_desc(desc); + u32 deco_dbg_reg, flags; + int i; /* Set the bit to request direct access to DECO0 */ topregs = (struct caam_full __iomem *)ctrlpriv->ctrl; @@ -100,36 +96,221 @@ static int instantiate_rng(struct device *ctrldev) if (!timeout) { dev_err(ctrldev, "failed to acquire DECO 0\n"); - ret = -EIO; - goto out; + clrbits32(&topregs->ctrl.deco_rq, DECORR_RQD0ENABLE); + return -ENODEV; } for (i = 0; i < desc_len(desc); i++) - topregs->deco.descbuf[i] = *(desc + i); + wr_reg32(&topregs->deco.descbuf[i], *(desc + i)); - wr_reg32(&topregs->deco.jr_ctl_hi, DECO_JQCR_WHL | DECO_JQCR_FOUR); + flags = DECO_JQCR_WHL; + /* + * If the descriptor length is longer than 4 words, then the + * FOUR bit in JRCTRL register must be set. + */ + if (desc_len(desc) >= 4) + flags |= DECO_JQCR_FOUR; + + /* Instruct the DECO to execute it */ + wr_reg32(&topregs->deco.jr_ctl_hi, flags); timeout = 10000000; - while ((rd_reg32(&topregs->deco.desc_dbg) & DECO_DBG_VALID) && - --timeout) + do { + deco_dbg_reg = rd_reg32(&topregs->deco.desc_dbg); + /* + * If an error occured in the descriptor, then + * the DECO status field will be set to 0x0D + */ + if ((deco_dbg_reg & DESC_DBG_DECO_STAT_MASK) == + DESC_DBG_DECO_STAT_HOST_ERR) + break; cpu_relax(); + } while ((deco_dbg_reg & DESC_DBG_DECO_STAT_VALID) && --timeout); - if (!timeout) { - dev_err(ctrldev, "failed to instantiate RNG\n"); - ret = -EIO; - } + *status = rd_reg32(&topregs->deco.op_status_hi) & + DECO_OP_STATUS_HI_ERR_MASK; + /* Mark the DECO as free */ clrbits32(&topregs->ctrl.deco_rq, DECORR_RQD0ENABLE); -out: + + if (!timeout) + return -EAGAIN; + + return 0; +} + +/* + * instantiate_rng - builds and executes a descriptor on DECO0, + * which initializes the RNG block. + * @ctrldev - pointer to device + * @state_handle_mask - bitmask containing the instantiation status + * for the RNG4 state handles which exist in + * the RNG4 block: 1 if it's been instantiated + * by an external entry, 0 otherwise. + * @gen_sk - generate data to be loaded into the JDKEK, TDKEK and TDSK; + * Caution: this can be done only once; if the keys need to be + * regenerated, a POR is required + * + * Return: - 0 if no error occurred + * - -ENOMEM if there isn't enough memory to allocate the descriptor + * - -ENODEV if DECO0 couldn't be acquired + * - -EAGAIN if an error occurred when executing the descriptor + * f.i. there was a RNG hardware error due to not "good enough" + * entropy being aquired. + */ +static int instantiate_rng(struct device *ctrldev, int state_handle_mask, + int gen_sk) +{ + struct caam_drv_private *ctrlpriv = dev_get_drvdata(ctrldev); + struct caam_full __iomem *topregs; + struct rng4tst __iomem *r4tst; + u32 *desc, status, rdsta_val; + int ret = 0, sh_idx; + + topregs = (struct caam_full __iomem *)ctrlpriv->ctrl; + r4tst = &topregs->ctrl.r4tst[0]; + + desc = kmalloc(CAAM_CMD_SZ * 7, GFP_KERNEL); + if (!desc) + return -ENOMEM; + + for (sh_idx = 0; sh_idx < RNG4_MAX_HANDLES; sh_idx++) { + /* + * If the corresponding bit is set, this state handle + * was initialized by somebody else, so it's left alone. + */ + if ((1 << sh_idx) & state_handle_mask) + continue; + + /* Create the descriptor for instantiating RNG State Handle */ + build_instantiation_desc(desc, sh_idx, gen_sk); + + /* Try to run it through DECO0 */ + ret = run_descriptor_deco0(ctrldev, desc, &status); + + /* + * If ret is not 0, or descriptor status is not 0, then + * something went wrong. No need to try the next state + * handle (if available), bail out here. + * Also, if for some reason, the State Handle didn't get + * instantiated although the descriptor has finished + * without any error (HW optimizations for later + * CAAM eras), then try again. + */ + rdsta_val = + rd_reg32(&topregs->ctrl.r4tst[0].rdsta) & RDSTA_IFMASK; + if (status || !(rdsta_val & (1 << sh_idx))) + ret = -EAGAIN; + if (ret) + break; + + dev_info(ctrldev, "Instantiated RNG4 SH%d\n", sh_idx); + /* Clear the contents before recreating the descriptor */ + memset(desc, 0x00, CAAM_CMD_SZ * 7); + } + kfree(desc); + return ret; } /* - * By default, the TRNG runs for 200 clocks per sample; - * 1600 clocks per sample generates better entropy. + * deinstantiate_rng - builds and executes a descriptor on DECO0, + * which deinitializes the RNG block. + * @ctrldev - pointer to device + * @state_handle_mask - bitmask containing the instantiation status + * for the RNG4 state handles which exist in + * the RNG4 block: 1 if it's been instantiated + * + * Return: - 0 if no error occurred + * - -ENOMEM if there isn't enough memory to allocate the descriptor + * - -ENODEV if DECO0 couldn't be acquired + * - -EAGAIN if an error occurred when executing the descriptor */ -static void kick_trng(struct platform_device *pdev) +static int deinstantiate_rng(struct device *ctrldev, int state_handle_mask) +{ + u32 *desc, status; + int sh_idx, ret = 0; + + desc = kmalloc(CAAM_CMD_SZ * 3, GFP_KERNEL); + if (!desc) + return -ENOMEM; + + for (sh_idx = 0; sh_idx < RNG4_MAX_HANDLES; sh_idx++) { + /* + * If the corresponding bit is set, then it means the state + * handle was initialized by us, and thus it needs to be + * deintialized as well + */ + if ((1 << sh_idx) & state_handle_mask) { + /* + * Create the descriptor for deinstantating this state + * handle + */ + build_deinstantiation_desc(desc, sh_idx); + + /* Try to run it through DECO0 */ + ret = run_descriptor_deco0(ctrldev, desc, &status); + + if (ret || status) { + dev_err(ctrldev, + "Failed to deinstantiate RNG4 SH%d\n", + sh_idx); + break; + } + dev_info(ctrldev, "Deinstantiated RNG4 SH%d\n", sh_idx); + } + } + + kfree(desc); + + return ret; +} + +static int caam_remove(struct platform_device *pdev) +{ + struct device *ctrldev; + struct caam_drv_private *ctrlpriv; + struct caam_drv_private_jr *jrpriv; + struct caam_full __iomem *topregs; + int ring, ret = 0; + + ctrldev = &pdev->dev; + ctrlpriv = dev_get_drvdata(ctrldev); + topregs = (struct caam_full __iomem *)ctrlpriv->ctrl; + + /* shut down JobRs */ + for (ring = 0; ring < ctrlpriv->total_jobrs; ring++) { + ret |= caam_jr_shutdown(ctrlpriv->jrdev[ring]); + jrpriv = dev_get_drvdata(ctrlpriv->jrdev[ring]); + irq_dispose_mapping(jrpriv->irq); + } + + /* De-initialize RNG state handles initialized by this driver. */ + if (ctrlpriv->rng4_sh_init) + deinstantiate_rng(ctrldev, ctrlpriv->rng4_sh_init); + + /* Shut down debug views */ +#ifdef CONFIG_DEBUG_FS + debugfs_remove_recursive(ctrlpriv->dfs_root); +#endif + + /* Unmap controller region */ + iounmap(&topregs->ctrl); + + kfree(ctrlpriv->jrdev); + kfree(ctrlpriv); + + return ret; +} + +/* + * kick_trng - sets the various parameters for enabling the initialization + * of the RNG4 block in CAAM + * @pdev - pointer to the platform device + * @ent_delay - Defines the length (in system clocks) of each entropy sample. + */ +static void kick_trng(struct platform_device *pdev, int ent_delay) { struct device *ctrldev = &pdev->dev; struct caam_drv_private *ctrlpriv = dev_get_drvdata(ctrldev); @@ -142,14 +323,31 @@ static void kick_trng(struct platform_device *pdev) /* put RNG4 into program mode */ setbits32(&r4tst->rtmctl, RTMCTL_PRGM); - /* 1600 clocks per sample */ + + /* + * Performance-wise, it does not make sense to + * set the delay to a value that is lower + * than the last one that worked (i.e. the state handles + * were instantiated properly. Thus, instead of wasting + * time trying to set the values controlling the sample + * frequency, the function simply returns. + */ + val = (rd_reg32(&r4tst->rtsdctl) & RTSDCTL_ENT_DLY_MASK) + >> RTSDCTL_ENT_DLY_SHIFT; + if (ent_delay <= val) { + /* put RNG4 into run mode */ + clrbits32(&r4tst->rtmctl, RTMCTL_PRGM); + return; + } + val = rd_reg32(&r4tst->rtsdctl); - val = (val & ~RTSDCTL_ENT_DLY_MASK) | (1600 << RTSDCTL_ENT_DLY_SHIFT); + val = (val & ~RTSDCTL_ENT_DLY_MASK) | + (ent_delay << RTSDCTL_ENT_DLY_SHIFT); wr_reg32(&r4tst->rtsdctl, val); - /* min. freq. count */ - wr_reg32(&r4tst->rtfrqmin, 400); - /* max. freq. count */ - wr_reg32(&r4tst->rtfrqmax, 6400); + /* min. freq. count, equal to 1/4 of the entropy sample length */ + wr_reg32(&r4tst->rtfrqmin, ent_delay >> 2); + /* max. freq. count, equal to 8 times the entropy sample length */ + wr_reg32(&r4tst->rtfrqmax, ent_delay << 3); /* put RNG4 into run mode */ clrbits32(&r4tst->rtmctl, RTMCTL_PRGM); } @@ -190,7 +388,7 @@ EXPORT_SYMBOL(caam_get_era); /* Probe routine for CAAM top (controller) level */ static int caam_probe(struct platform_device *pdev) { - int ret, ring, rspec; + int ret, ring, rspec, gen_sk, ent_delay = RTSDCTL_ENT_DLY_MIN; u64 caam_id; struct device *dev; struct device_node *nprop, *np; @@ -296,16 +494,55 @@ static int caam_probe(struct platform_device *pdev) /* * If SEC has RNG version >= 4 and RNG state handle has not been - * already instantiated ,do RNG instantiation + * already instantiated, do RNG instantiation */ - if ((cha_vid & CHA_ID_RNG_MASK) >> CHA_ID_RNG_SHIFT >= 4 && - !(rd_reg32(&topregs->ctrl.r4tst[0].rdsta) & RDSTA_IF0)) { - kick_trng(pdev); - ret = instantiate_rng(dev); + if ((cha_vid & CHA_ID_RNG_MASK) >> CHA_ID_RNG_SHIFT >= 4) { + ctrlpriv->rng4_sh_init = + rd_reg32(&topregs->ctrl.r4tst[0].rdsta); + /* + * If the secure keys (TDKEK, JDKEK, TDSK), were already + * generated, signal this to the function that is instantiating + * the state handles. An error would occur if RNG4 attempts + * to regenerate these keys before the next POR. + */ + gen_sk = ctrlpriv->rng4_sh_init & RDSTA_SKVN ? 0 : 1; + ctrlpriv->rng4_sh_init &= RDSTA_IFMASK; + do { + int inst_handles = + rd_reg32(&topregs->ctrl.r4tst[0].rdsta) & + RDSTA_IFMASK; + /* + * If either SH were instantiated by somebody else + * (e.g. u-boot) then it is assumed that the entropy + * parameters are properly set and thus the function + * setting these (kick_trng(...)) is skipped. + * Also, if a handle was instantiated, do not change + * the TRNG parameters. + */ + if (!(ctrlpriv->rng4_sh_init || inst_handles)) { + kick_trng(pdev, ent_delay); + ent_delay += 400; + } + /* + * if instantiate_rng(...) fails, the loop will rerun + * and the kick_trng(...) function will modfiy the + * upper and lower limits of the entropy sampling + * interval, leading to a sucessful initialization of + * the RNG. + */ + ret = instantiate_rng(dev, inst_handles, + gen_sk); + } while ((ret == -EAGAIN) && (ent_delay < RTSDCTL_ENT_DLY_MAX)); if (ret) { + dev_err(dev, "failed to instantiate RNG"); caam_remove(pdev); return ret; } + /* + * Set handles init'ed by this module as the complement of the + * already initialized ones + */ + ctrlpriv->rng4_sh_init = ~ctrlpriv->rng4_sh_init & RDSTA_IFMASK; /* Enable RDB bit so that RNG works faster */ setbits32(&topregs->ctrl.scfgr, SCFGR_RDBENABLE);