[PATCH v2 6/6] irqchip/stm32-exti: Simplify irq description table

From: Antonio Borneo
Date: Mon Jun 06 2022 - 12:30:20 EST


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@xxxxxxxxxxx>
---
drivers/irqchip/irq-stm32-exti.c | 220 ++++++++++++++-----------------
1 file changed, 101 insertions(+), 119 deletions(-)

diff --git a/drivers/irqchip/irq-stm32-exti.c b/drivers/irqchip/irq-stm32-exti.c
index 045589627e67..a73763d475f0 100644
--- 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);
--
2.36.1