On Tue, 29 Aug 2023 10:21:18 +0100,
Dmitry Baryshkov <[email protected]> wrote:
>
> From: Neil Armstrong <[email protected]>
>
> Starting from HW version 3.2 the IRQ_ENABLE bit has moved to the
> IRQ_i_CFG register and requires a change of the driver to avoid
> writing into an undefined register address.
>
> Get the HW version from registers and set the IRQ_ENABLE bit to the
> correct register depending on the HW version.
>
> Signed-off-by: Neil Armstrong <[email protected]>
> [DB: fix crash on sm8150 DTs which listed short PDC region]
> Signed-off-by: Dmitry Baryshkov <[email protected]>
> ---
> drivers/irqchip/qcom-pdc.c | 73 ++++++++++++++++++++++++++++++--------
> 1 file changed, 59 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/irqchip/qcom-pdc.c b/drivers/irqchip/qcom-pdc.c
> index a32c0d28d038..f9f44b494b1d 100644
> --- a/drivers/irqchip/qcom-pdc.c
> +++ b/drivers/irqchip/qcom-pdc.c
> @@ -22,9 +22,22 @@
>
> #define PDC_MAX_GPIO_IRQS 256
>
> +/* Valid only on HW version < 3.2 */
> #define IRQ_ENABLE_BANK 0x10
> #define IRQ_i_CFG 0x110
>
> +/* Valid only on HW version >= 3.2 */
> +#define IRQ_i_CFG_IRQ_ENABLE 3
> +
> +#define IRQ_i_CFG_TYPE_MASK GENMASK(2, 0)
> +
> +#define PDC_VERSION 0x1000
That's an offset, right? Maybe spelling it as such would make this
more readable...
> +
> +/* Notable PDC versions */
> +enum {
> + PDC_VERSION_3_2 = 0x30200,
... specially when reading this (why is it all of a sudden an enum?).
> +};
> +
> struct pdc_pin_region {
> u32 pin_base;
> u32 parent_base;
> @@ -37,6 +50,7 @@ static DEFINE_RAW_SPINLOCK(pdc_lock);
> static void __iomem *pdc_base;
> static struct pdc_pin_region *pdc_region;
> static int pdc_region_cnt;
> +static unsigned int pdc_version;
>
> static void pdc_reg_write(int reg, u32 i, u32 val)
> {
> @@ -53,15 +67,22 @@ static void pdc_enable_intr(struct irq_data *d, bool on)
> int pin_out = d->hwirq;
> unsigned long enable;
> unsigned long flags;
> - u32 index, mask;
> -
> - index = pin_out / 32;
> - mask = pin_out % 32;
>
> raw_spin_lock_irqsave(&pdc_lock, flags);
> - enable = pdc_reg_read(IRQ_ENABLE_BANK, index);
> - __assign_bit(mask, &enable, on);
> - pdc_reg_write(IRQ_ENABLE_BANK, index, enable);
> + if (pdc_version < PDC_VERSION_3_2) {
> + u32 index, mask;
> +
> + index = pin_out / 32;
> + mask = pin_out % 32;
> +
> + enable = pdc_reg_read(IRQ_ENABLE_BANK, index);
> + __assign_bit(mask, &enable, on);
> + pdc_reg_write(IRQ_ENABLE_BANK, index, enable);
> + } else {
> + enable = pdc_reg_read(IRQ_i_CFG, pin_out);
> + __assign_bit(IRQ_i_CFG_IRQ_ENABLE, &enable, on);
> + pdc_reg_write(IRQ_i_CFG, pin_out, enable);
> + }
> raw_spin_unlock_irqrestore(&pdc_lock, flags);
> }
>
> @@ -142,6 +163,7 @@ static int qcom_pdc_gic_set_type(struct irq_data *d, unsigned int type)
> }
>
> old_pdc_type = pdc_reg_read(IRQ_i_CFG, d->hwirq);
> + pdc_type |= (old_pdc_type & ~IRQ_i_CFG_TYPE_MASK);
> pdc_reg_write(IRQ_i_CFG, d->hwirq, pdc_type);
>
> ret = irq_chip_set_type_parent(d, type);
> @@ -246,7 +268,7 @@ static const struct irq_domain_ops qcom_pdc_ops = {
> static int pdc_setup_pin_mapping(struct device_node *np)
> {
> int ret, n, i;
> - u32 irq_index, reg_index, val;
> + unsigned long val;
>
> n = of_property_count_elems_of_size(np, "qcom,pdc-ranges", sizeof(u32));
> if (n <= 0 || n % 3)
> @@ -277,28 +299,51 @@ static int pdc_setup_pin_mapping(struct device_node *np)
> return ret;
>
> for (i = 0; i < pdc_region[n].cnt; i++) {
> - reg_index = (i + pdc_region[n].pin_base) >> 5;
> - irq_index = (i + pdc_region[n].pin_base) & 0x1f;
> - val = pdc_reg_read(IRQ_ENABLE_BANK, reg_index);
> - val &= ~BIT(irq_index);
> - pdc_reg_write(IRQ_ENABLE_BANK, reg_index, val);
> + if (pdc_version < PDC_VERSION_3_2) {
> + u32 irq_index, reg_index;
> +
> + reg_index = (i + pdc_region[n].pin_base) >> 5;
> + irq_index = (i + pdc_region[n].pin_base) & 0x1f;
> + val = pdc_reg_read(IRQ_ENABLE_BANK, reg_index);
> + __assign_bit(irq_index, &val, 0);
> + pdc_reg_write(IRQ_ENABLE_BANK, reg_index, val);
> + } else {
> + u32 irq;
> +
> + irq = i + pdc_region[n].pin_base;
> + val = pdc_reg_read(IRQ_i_CFG, irq);
> + __assign_bit(IRQ_i_CFG_IRQ_ENABLE, &val, 0);
> + pdc_reg_write(IRQ_i_CFG, irq, val);
> + }
This is a bit backwards. The PDC version doesn't change within the
loop. But more importantly, this is a rewrite of the pdc_enable_intr()
helper, only taking raw indices instead of an irq_data pointer.
Surely this can be written in a better way.
> }
> }
>
> return 0;
> }
>
> +#define QCOM_PDC_SIZE 0x30000
> +
> static int qcom_pdc_init(struct device_node *node, struct device_node *parent)
> {
> struct irq_domain *parent_domain, *pdc_domain;
> + struct resource res;
> + resource_size_t res_size;
nit: swapping these two lines will make things vaguely more readable.
> int ret;
>
> - pdc_base = of_iomap(node, 0);
> + /* compat with old sm8150 DT which had very small region for PDC */
> + if (of_address_to_resource(node, 0, &res))
> + return -EINVAL;
> +
> + res_size = max_t(resource_size_t, resource_size(&res), QCOM_PDC_SIZE);
This probably deserves a warning so that DTs that do not have the
correct size get fixed.
Thanks,
M.
--
Without deviation from the norm, progress is not possible.