The function is getting out of control, it has too many goto statements and would be too complicated for adding a feature two-level device table. So, it is time for us to cleanup and move some of the logic to a separate function without affecting the existing functionality.
Signed-off-by: Shanker Donthineni <shank...@codeaurora.org> --- This patch is based on Marc Zyngier's branch https://git.kernel.org/cgit/linux/kernel/git/maz/arm-platforms.git/log/?h=irq/irqchip-4.7 drivers/irqchip/irq-gic-v3-its.c | 256 ++++++++++++++++++++----------------- include/linux/irqchip/arm-gic-v3.h | 3 + 2 files changed, 144 insertions(+), 115 deletions(-) diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c index 6bd881b..b23e00c 100644 --- a/drivers/irqchip/irq-gic-v3-its.c +++ b/drivers/irqchip/irq-gic-v3-its.c @@ -55,13 +55,15 @@ struct its_collection { }; /* - * The ITS_BASER structure - contains memory information and cached - * value of BASER register configuration. + * The ITS_BASER structure - contains memory information, cached value + * of BASER register configuration, ioremaped address and page size. */ struct its_baser { + void __iomem *hwreg; void *base; u64 val; u32 order; + u32 psz; }; /* @@ -823,27 +825,135 @@ static void its_free_tables(struct its_node *its) } } +static int its_baser_setup(struct its_node *its, struct its_baser *baser, + u32 order, u64 indirect) +{ + u64 val = readq_relaxed(baser->hwreg); + u64 type = GITS_BASER_TYPE(val); + u64 entry_size = GITS_BASER_ENTRY_SIZE(val); + int psz, alloc_pages; + u64 cache, shr, tmp; + void *base; + + /* Do first attempt with the requested attributes */ + cache = baser->val & GITS_BASER_CACHEABILITY_MASK; + shr = baser->val & GITS_BASER_SHAREABILITY_MASK; + psz = baser->psz; + +retry_alloc_baser: + alloc_pages = (PAGE_ORDER_TO_SIZE(order) / psz); + if (alloc_pages > GITS_BASER_PAGES_MAX) { + pr_warn("ITS@%lx: %s too large, reduce ITS pages %u->%u\n", + its->phys_base, its_base_type_string[type], + alloc_pages, GITS_BASER_PAGES_MAX); + alloc_pages = GITS_BASER_PAGES_MAX; + order = get_order(GITS_BASER_PAGES_MAX * psz); + } + + base = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, order); + if (!base) + return -ENOMEM; + +retry_baser: + val = (virt_to_phys(base) | + (type << GITS_BASER_TYPE_SHIFT) | + ((entry_size - 1) << GITS_BASER_ENTRY_SIZE_SHIFT) | + ((alloc_pages - 1) << GITS_BASER_PAGES_SHIFT) | + cache | + shr | + indirect | + GITS_BASER_VALID); + + switch (psz) { + case SZ_4K: + val |= GITS_BASER_PAGE_SIZE_4K; + break; + case SZ_16K: + val |= GITS_BASER_PAGE_SIZE_16K; + break; + case SZ_64K: + val |= GITS_BASER_PAGE_SIZE_64K; + break; + } + + writeq_relaxed(val, baser->hwreg); + tmp = readq_relaxed(baser->hwreg); + + if ((val ^ tmp) & GITS_BASER_SHAREABILITY_MASK) { + /* + * Shareability didn't stick. Just use + * whatever the read reported, which is likely + * to be the only thing this redistributor + * supports. If that's zero, make it + * non-cacheable as well. + */ + shr = tmp & GITS_BASER_SHAREABILITY_MASK; + if (!shr) { + cache = GITS_BASER_nC; + __flush_dcache_area(base, PAGE_ORDER_TO_SIZE(order)); + } + goto retry_baser; + } + + if ((val ^ tmp) & GITS_BASER_PAGE_SIZE_MASK) { + /* + * Page size didn't stick. Let's try a smaller + * size and retry. If we reach 4K, then + * something is horribly wrong... + */ + free_pages((unsigned long)base, order); + baser->base = NULL; + + switch (psz) { + case SZ_16K: + psz = SZ_4K; + goto retry_alloc_baser; + case SZ_64K: + psz = SZ_16K; + goto retry_alloc_baser; + } + } + + if (val != tmp) { + pr_err("ITS@%lx: %s doesn't stick: %lx %lx\n", + its->phys_base, its_base_type_string[type], + (unsigned long) val, (unsigned long) tmp); + free_pages((unsigned long)base, order); + return -ENXIO; + } + + baser->base = base; + baser->order = order; + baser->psz = psz; + baser->val = val; + tmp = indirect ? GITS_LVL1_ENTRY_SIZE : entry_size; + + pr_info("ITS@%lx: allocated %d %s @%lx (%s, esz %d, psz %dK, shr %d)\n", + its->phys_base, (int)(PAGE_ORDER_TO_SIZE(order) / tmp), + its_base_type_string[type], + (unsigned long)virt_to_phys(base), + indirect ? "indirect" : "flat", (int)entry_size, + psz / SZ_1K, (int)shr >> GITS_BASER_SHAREABILITY_SHIFT); + + return 0; +} + static int its_alloc_tables(const char *node_name, struct its_node *its) { - int err; - int i; - int psz = SZ_64K; + u64 typer = readq_relaxed(its->base + GITS_TYPER); + u32 ids = GITS_TYPER_DEVBITS(typer); u64 shr = GITS_BASER_InnerShareable; - u64 cache; - u64 typer; - u32 ids; + u64 cache = GITS_BASER_WaWb; + int psz = SZ_64K; + int err, i; if (its->flags & ITS_FLAGS_WORKAROUND_CAVIUM_22375) { /* * erratum 22375: only alloc 8MB table size * erratum 24313: ignore memory access type */ - cache = 0; + cache = GITS_BASER_nCnB; ids = 0x14; /* 20 bits, 8MB */ - } else { - cache = GITS_BASER_WaWb; - typer = readq_relaxed(its->base + GITS_TYPER); - ids = GITS_TYPER_DEVBITS(typer); } its->device_ids = ids; @@ -853,13 +963,16 @@ static int its_alloc_tables(const char *node_name, struct its_node *its) u64 type = GITS_BASER_TYPE(val); u64 entry_size = GITS_BASER_ENTRY_SIZE(val); int order = get_order(psz); - int alloc_pages; - u64 tmp; - void *base; + struct its_baser *baser = its->tables + i; if (type == GITS_BASER_TYPE_NONE) continue; + /* Set preferred settings for this BASERn */ + baser->hwreg = its->base + GITS_BASER + i * 8; + baser->val = cache | shr; + baser->psz = psz; + /* * Allocate as many entries as required to fit the * range of device IDs that the ITS can grok... The ID @@ -875,115 +988,28 @@ static int its_alloc_tables(const char *node_name, struct its_node *its) * smaller than that. If the requested allocation * is smaller, round up to the default page granule. */ - order = max(get_order((1UL << ids) * entry_size), - order); + order = max(get_order(entry_size << ids), order); if (order >= MAX_ORDER) { order = MAX_ORDER - 1; - pr_warn("%s: Device Table too large, reduce its page order to %u\n", - node_name, order); - } - } - -retry_alloc_baser: - alloc_pages = (PAGE_ORDER_TO_SIZE(order) / psz); - if (alloc_pages > GITS_BASER_PAGES_MAX) { - alloc_pages = GITS_BASER_PAGES_MAX; - order = get_order(GITS_BASER_PAGES_MAX * psz); - pr_warn("%s: Device Table too large, reduce its page order to %u (%u pages)\n", - node_name, order, alloc_pages); - } - - base = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, order); - if (!base) { - err = -ENOMEM; - goto out_free; - } - - its->tables[i].base = base; - its->tables[i].order = order; - -retry_baser: - val = (virt_to_phys(base) | - (type << GITS_BASER_TYPE_SHIFT) | - ((entry_size - 1) << GITS_BASER_ENTRY_SIZE_SHIFT) | - cache | - shr | - GITS_BASER_VALID); - - switch (psz) { - case SZ_4K: - val |= GITS_BASER_PAGE_SIZE_4K; - break; - case SZ_16K: - val |= GITS_BASER_PAGE_SIZE_16K; - break; - case SZ_64K: - val |= GITS_BASER_PAGE_SIZE_64K; - break; - } - - val |= alloc_pages - 1; - its->tables[i].val = val; - - writeq_relaxed(val, its->base + GITS_BASER + i * 8); - tmp = readq_relaxed(its->base + GITS_BASER + i * 8); - - if ((val ^ tmp) & GITS_BASER_SHAREABILITY_MASK) { - /* - * Shareability didn't stick. Just use - * whatever the read reported, which is likely - * to be the only thing this redistributor - * supports. If that's zero, make it - * non-cacheable as well. - */ - shr = tmp & GITS_BASER_SHAREABILITY_MASK; - if (!shr) { - cache = GITS_BASER_nC; - __flush_dcache_area(base, PAGE_ORDER_TO_SIZE(order)); + ids = ilog2(PAGE_ORDER_TO_SIZE(order) / entry_size); + pr_warn("ITS@%lx:: Device Table too large, reduce ids %u->%u\n", + its->phys_base, its->device_ids, ids); } - goto retry_baser; } - if ((val ^ tmp) & GITS_BASER_PAGE_SIZE_MASK) { - /* - * Page size didn't stick. Let's try a smaller - * size and retry. If we reach 4K, then - * something is horribly wrong... - */ - free_pages((unsigned long)base, order); - its->tables[i].base = NULL; - - switch (psz) { - case SZ_16K: - psz = SZ_4K; - goto retry_alloc_baser; - case SZ_64K: - psz = SZ_16K; - goto retry_alloc_baser; - } - } - - if (val != tmp) { - pr_err("ITS: %s: GITS_BASER%d doesn't stick: %lx %lx\n", - node_name, i, - (unsigned long) val, (unsigned long) tmp); - err = -ENXIO; - goto out_free; + err = its_baser_setup(its, baser, order, 0); + if (err < 0) { + its_free_tables(its); + return err; } - pr_info("ITS: allocated %d %s @%lx (psz %dK, shr %d)\n", - (int)(PAGE_ORDER_TO_SIZE(order) / entry_size), - its_base_type_string[type], - (unsigned long)virt_to_phys(base), - psz / SZ_1K, (int)shr >> GITS_BASER_SHAREABILITY_SHIFT); + /* Update settings which will be used for next BASERn */ + psz = baser->psz; + cache = baser->val & GITS_BASER_CACHEABILITY_MASK; + shr = baser->val & GITS_BASER_SHAREABILITY_MASK; } return 0; - -out_free: - its_free_tables(its); - - return err; } static int its_alloc_collections(struct its_node *its) diff --git a/include/linux/irqchip/arm-gic-v3.h b/include/linux/irqchip/arm-gic-v3.h index 9e6fdd3..7f917b9 100644 --- a/include/linux/irqchip/arm-gic-v3.h +++ b/include/linux/irqchip/arm-gic-v3.h @@ -204,6 +204,7 @@ #define GITS_BASER_NR_REGS 8 #define GITS_BASER_VALID (1UL << 63) +#define GITS_BASER_INDIRECT (1UL << 62) #define GITS_BASER_nCnB (0UL << 59) #define GITS_BASER_nC (1UL << 59) #define GITS_BASER_RaWt (2UL << 59) @@ -228,6 +229,7 @@ #define GITS_BASER_PAGE_SIZE_64K (2UL << GITS_BASER_PAGE_SIZE_SHIFT) #define GITS_BASER_PAGE_SIZE_MASK (3UL << GITS_BASER_PAGE_SIZE_SHIFT) #define GITS_BASER_PAGES_MAX 256 +#define GITS_BASER_PAGES_SHIFT (0) #define GITS_BASER_TYPE_NONE 0 #define GITS_BASER_TYPE_DEVICE 1 @@ -238,6 +240,7 @@ #define GITS_BASER_TYPE_RESERVED6 6 #define GITS_BASER_TYPE_RESERVED7 7 +#define GITS_LVL1_ENTRY_SIZE (8UL) /* * ITS commands */ -- Qualcomm Technologies, Inc. on behalf of Qualcomm Innovation Center, Inc. Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project
