irqchip/stm32-exti: Simplify irq description table

Having removed the event trigger type from struct stm32_desc_irq
makes worthless keep using a struct.

Replace the struct by a single dimension array and use 8 bit type
to reduce the overal memory footprint.
On armv7a this patch reduces by 7% the size of the driver, from
   text    data     bss     dec     hex filename
   6977     424       4    7405    1ced irq-stm32-exti.o
to
   6449     424       4    6877    1add irq-stm32-exti.o

Signed-off-by: Antonio Borneo <antonio.borneo@foss.st.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220606162757.415354-7-antonio.borneo@foss.st.com

diff --git a/drivers/irqchip/irq-stm32-exti.c b/drivers/irqchip/irq-stm32-exti.c
index 045589627e67659c1b74f24b6bbb63037616140b..a73763d475f04e277f4794fe7ccc048d8e6313bc 100644 (file)
--- a/drivers/irqchip/irq-stm32-exti.c
+++ b/drivers/irqchip/irq-stm32-exti.c
@@ -39,16 +39,10 @@ struct stm32_exti_bank {
 
 #define UNDEF_REG ~0
 
-struct stm32_desc_irq {
-       u32 exti;
-       u32 irq_parent;
-};
-
 struct stm32_exti_drv_data {
        const struct stm32_exti_bank **exti_banks;
-       const struct stm32_desc_irq *desc_irqs;
+       const u8 *desc_irqs;
        u32 bank_nr;
-       u32 irq_nr;
 };
 
 struct stm32_exti_chip_data {
@@ -176,126 +170,114 @@ static const struct stm32_exti_bank *stm32mp1_exti_banks[] = {
 static struct irq_chip stm32_exti_h_chip;
 static struct irq_chip stm32_exti_h_chip_direct;
 
-static const struct stm32_desc_irq stm32mp1_desc_irq[] = {
-       { .exti = 0, .irq_parent = 6 },
-       { .exti = 1, .irq_parent = 7 },
-       { .exti = 2, .irq_parent = 8 },
-       { .exti = 3, .irq_parent = 9 },
-       { .exti = 4, .irq_parent = 10 },
-       { .exti = 5, .irq_parent = 23 },
-       { .exti = 6, .irq_parent = 64 },
-       { .exti = 7, .irq_parent = 65 },
-       { .exti = 8, .irq_parent = 66 },
-       { .exti = 9, .irq_parent = 67 },
-       { .exti = 10, .irq_parent = 40 },
-       { .exti = 11, .irq_parent = 42 },
-       { .exti = 12, .irq_parent = 76 },
-       { .exti = 13, .irq_parent = 77 },
-       { .exti = 14, .irq_parent = 121 },
-       { .exti = 15, .irq_parent = 127 },
-       { .exti = 16, .irq_parent = 1 },
-       { .exti = 19, .irq_parent = 3 },
-       { .exti = 21, .irq_parent = 31 },
-       { .exti = 22, .irq_parent = 33 },
-       { .exti = 23, .irq_parent = 72 },
-       { .exti = 24, .irq_parent = 95 },
-       { .exti = 25, .irq_parent = 107 },
-       { .exti = 26, .irq_parent = 37 },
-       { .exti = 27, .irq_parent = 38 },
-       { .exti = 28, .irq_parent = 39 },
-       { .exti = 29, .irq_parent = 71 },
-       { .exti = 30, .irq_parent = 52 },
-       { .exti = 31, .irq_parent = 53 },
-       { .exti = 32, .irq_parent = 82 },
-       { .exti = 33, .irq_parent = 83 },
-       { .exti = 47, .irq_parent = 93 },
-       { .exti = 48, .irq_parent = 138 },
-       { .exti = 50, .irq_parent = 139 },
-       { .exti = 52, .irq_parent = 140 },
-       { .exti = 53, .irq_parent = 141 },
-       { .exti = 54, .irq_parent = 135 },
-       { .exti = 61, .irq_parent = 100 },
-       { .exti = 65, .irq_parent = 144 },
-       { .exti = 68, .irq_parent = 143 },
-       { .exti = 70, .irq_parent = 62 },
-       { .exti = 73, .irq_parent = 129 },
+#define EXTI_INVALID_IRQ       U8_MAX
+#define STM32MP1_DESC_IRQ_SIZE (ARRAY_SIZE(stm32mp1_exti_banks) * IRQS_PER_BANK)
+
+static const u8 stm32mp1_desc_irq[] = {
+       /* default value */
+       [0 ... (STM32MP1_DESC_IRQ_SIZE - 1)] = EXTI_INVALID_IRQ,
+
+       [0] = 6,
+       [1] = 7,
+       [2] = 8,
+       [3] = 9,
+       [4] = 10,
+       [5] = 23,
+       [6] = 64,
+       [7] = 65,
+       [8] = 66,
+       [9] = 67,
+       [10] = 40,
+       [11] = 42,
+       [12] = 76,
+       [13] = 77,
+       [14] = 121,
+       [15] = 127,
+       [16] = 1,
+       [19] = 3,
+       [21] = 31,
+       [22] = 33,
+       [23] = 72,
+       [24] = 95,
+       [25] = 107,
+       [26] = 37,
+       [27] = 38,
+       [28] = 39,
+       [29] = 71,
+       [30] = 52,
+       [31] = 53,
+       [32] = 82,
+       [33] = 83,
+       [47] = 93,
+       [48] = 138,
+       [50] = 139,
+       [52] = 140,
+       [53] = 141,
+       [54] = 135,
+       [61] = 100,
+       [65] = 144,
+       [68] = 143,
+       [70] = 62,
+       [73] = 129,
 };
 
-static const struct stm32_desc_irq stm32mp13_desc_irq[] = {
-       { .exti = 0, .irq_parent = 6 },
-       { .exti = 1, .irq_parent = 7 },
-       { .exti = 2, .irq_parent = 8 },
-       { .exti = 3, .irq_parent = 9 },
-       { .exti = 4, .irq_parent = 10 },
-       { .exti = 5, .irq_parent = 24 },
-       { .exti = 6, .irq_parent = 65 },
-       { .exti = 7, .irq_parent = 66 },
-       { .exti = 8, .irq_parent = 67 },
-       { .exti = 9, .irq_parent = 68 },
-       { .exti = 10, .irq_parent = 41 },
-       { .exti = 11, .irq_parent = 43 },
-       { .exti = 12, .irq_parent = 77 },
-       { .exti = 13, .irq_parent = 78 },
-       { .exti = 14, .irq_parent = 106 },
-       { .exti = 15, .irq_parent = 109 },
-       { .exti = 16, .irq_parent = 1 },
-       { .exti = 19, .irq_parent = 3 },
-       { .exti = 21, .irq_parent = 32 },
-       { .exti = 22, .irq_parent = 34 },
-       { .exti = 23, .irq_parent = 73 },
-       { .exti = 24, .irq_parent = 93 },
-       { .exti = 25, .irq_parent = 114 },
-       { .exti = 26, .irq_parent = 38 },
-       { .exti = 27, .irq_parent = 39 },
-       { .exti = 28, .irq_parent = 40 },
-       { .exti = 29, .irq_parent = 72 },
-       { .exti = 30, .irq_parent = 53 },
-       { .exti = 31, .irq_parent = 54 },
-       { .exti = 32, .irq_parent = 83 },
-       { .exti = 33, .irq_parent = 84 },
-       { .exti = 44, .irq_parent = 96 },
-       { .exti = 47, .irq_parent = 92 },
-       { .exti = 48, .irq_parent = 116 },
-       { .exti = 50, .irq_parent = 117 },
-       { .exti = 52, .irq_parent = 118 },
-       { .exti = 53, .irq_parent = 119 },
-       { .exti = 68, .irq_parent = 63 },
-       { .exti = 70, .irq_parent = 98 },
+static const u8 stm32mp13_desc_irq[] = {
+       /* default value */
+       [0 ... (STM32MP1_DESC_IRQ_SIZE - 1)] = EXTI_INVALID_IRQ,
+
+       [0] = 6,
+       [1] = 7,
+       [2] = 8,
+       [3] = 9,
+       [4] = 10,
+       [5] = 24,
+       [6] = 65,
+       [7] = 66,
+       [8] = 67,
+       [9] = 68,
+       [10] = 41,
+       [11] = 43,
+       [12] = 77,
+       [13] = 78,
+       [14] = 106,
+       [15] = 109,
+       [16] = 1,
+       [19] = 3,
+       [21] = 32,
+       [22] = 34,
+       [23] = 73,
+       [24] = 93,
+       [25] = 114,
+       [26] = 38,
+       [27] = 39,
+       [28] = 40,
+       [29] = 72,
+       [30] = 53,
+       [31] = 54,
+       [32] = 83,
+       [33] = 84,
+       [44] = 96,
+       [47] = 92,
+       [48] = 116,
+       [50] = 117,
+       [52] = 118,
+       [53] = 119,
+       [68] = 63,
+       [70] = 98,
 };
 
 static const struct stm32_exti_drv_data stm32mp1_drv_data = {
        .exti_banks = stm32mp1_exti_banks,
        .bank_nr = ARRAY_SIZE(stm32mp1_exti_banks),
        .desc_irqs = stm32mp1_desc_irq,
-       .irq_nr = ARRAY_SIZE(stm32mp1_desc_irq),
 };
 
 static const struct stm32_exti_drv_data stm32mp13_drv_data = {
        .exti_banks = stm32mp1_exti_banks,
        .bank_nr = ARRAY_SIZE(stm32mp1_exti_banks),
        .desc_irqs = stm32mp13_desc_irq,
-       .irq_nr = ARRAY_SIZE(stm32mp13_desc_irq),
 };
 
-static const struct
-stm32_desc_irq *stm32_exti_get_desc(const struct stm32_exti_drv_data *drv_data,
-                                   irq_hw_number_t hwirq)
-{
-       const struct stm32_desc_irq *desc = NULL;
-       int i;
-
-       if (!drv_data->desc_irqs)
-               return NULL;
-
-       for (i = 0; i < drv_data->irq_nr; i++) {
-               desc = &drv_data->desc_irqs[i];
-               if (desc->exti == hwirq)
-                       break;
-       }
-
-       return desc;
-}
-
 static unsigned long stm32_exti_pending(struct irq_chip_generic *gc)
 {
        struct stm32_exti_chip_data *chip_data = gc->private;
@@ -713,7 +695,7 @@ static int stm32_exti_h_domain_alloc(struct irq_domain *dm,
 {
        struct stm32_exti_host_data *host_data = dm->host_data;
        struct stm32_exti_chip_data *chip_data;
-       const struct stm32_desc_irq *desc;
+       u8 desc_irq;
        struct irq_fwspec *fwspec = data;
        struct irq_fwspec p_fwspec;
        irq_hw_number_t hwirq;
@@ -728,21 +710,21 @@ static int stm32_exti_h_domain_alloc(struct irq_domain *dm,
        bank  = hwirq / IRQS_PER_BANK;
        chip_data = &host_data->chips_data[bank];
 
-
-       desc = stm32_exti_get_desc(host_data->drv_data, hwirq);
-       if (!desc)
-               return -EINVAL;
-
        event_trg = readl_relaxed(host_data->base + chip_data->reg_bank->trg_ofst);
        chip = (event_trg & BIT(hwirq % IRQS_PER_BANK)) ?
               &stm32_exti_h_chip : &stm32_exti_h_chip_direct;
 
        irq_domain_set_hwirq_and_chip(dm, virq, hwirq, chip, chip_data);
-       if (desc->irq_parent) {
+
+       if (!host_data->drv_data || !host_data->drv_data->desc_irqs)
+               return -EINVAL;
+
+       desc_irq = host_data->drv_data->desc_irqs[hwirq];
+       if (desc_irq != EXTI_INVALID_IRQ) {
                p_fwspec.fwnode = dm->parent->fwnode;
                p_fwspec.param_count = 3;
                p_fwspec.param[0] = GIC_SPI;
-               p_fwspec.param[1] = desc->irq_parent;
+               p_fwspec.param[1] = desc_irq;
                p_fwspec.param[2] = IRQ_TYPE_LEVEL_HIGH;
 
                return irq_domain_alloc_irqs_parent(dm, virq, 1, &p_fwspec);