Re: [RFC/PATCH v2 09/16] soc: bcm: bcm2835-power: Add support for BCM2711's Argon ASB

From: Phil Elwell
Date: Tue Feb 09 2021 - 08:20:54 EST

Hi Nicolas,

On Tue, 9 Feb 2021 at 13:00, Nicolas Saenz Julienne
<nsaenzjulienne@xxxxxxx> wrote:
>
> In BCM2711 the new ARGON ASB took over V3D. The old ASB is still present
> with the ISP and H264 bits, and V3D is in the same place in the new ASB
> as the old one.
>
> Use the fact that 'pm->argon_asb' is populated as a hint that we're on
> BCM2711. On top of that introduce the macro ASB_BASE() which will select
> the correct ASB register base, based on whether we're trying to access
> V3D and which platform we're on.

Please don't refer to this block as ARGON - it is the IP of Raspberry
Pi Trading and it's name is RPiVid.

> Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@xxxxxxx>
>
> ---
>
> Changes since v1:
> - Correct names
>
> drivers/soc/bcm/bcm2835-power.c | 68 ++++++++++++++++++++-------------
> 1 file changed, 42 insertions(+), 26 deletions(-)
>
> diff --git a/drivers/soc/bcm/bcm2835-power.c b/drivers/soc/bcm/bcm2835-power.c
> index 59b8abfc5617..42e105758b47 100644
> --- a/drivers/soc/bcm/bcm2835-power.c
> +++ b/drivers/soc/bcm/bcm2835-power.c
> @@ -126,8 +126,9 @@
>
> #define ASB_AXI_BRDG_ID 0x20
>
> -#define ASB_READ(reg) readl(power->rpivid_asb + (reg))
> -#define ASB_WRITE(reg, val) writel(PM_PASSWORD | (val), power->rpivid_asb + (reg))
> +#define ASB_BASE(is_v3d) (is_v3d && power->argon_asb ? power->argon_asb : power->rpivid_asb)
> +#define ASB_READ(reg, is_v3d) readl(ASB_BASE(is_v3d) + (reg))
> +#define ASB_WRITE(reg, val, is_v3d) writel(PM_PASSWORD | (val), ASB_BASE(is_v3d) + (reg))
>
> struct bcm2835_power_domain {
> struct generic_pm_domain base;
> @@ -142,13 +143,16 @@ struct bcm2835_power {
> void __iomem *base;
> /* RPiVid bridge registers. */
> void __iomem *rpivid_asb;
> + /* Argon bridge registers. */
> + void __iomem *argon_asb;
>
> struct genpd_onecell_data pd_xlate;
> struct bcm2835_power_domain domains[BCM2835_POWER_DOMAIN_COUNT];
> struct reset_controller_dev reset;
> };
>
> -static int bcm2835_asb_enable(struct bcm2835_power *power, u32 reg)
> +static int bcm2835_asb_enable(struct bcm2835_power *power, u32 reg,
> + bool is_v3d)
> {
> u64 start;
>
> @@ -158,8 +162,8 @@ static int bcm2835_asb_enable(struct bcm2835_power *power, u32 reg)
> start = ktime_get_ns();
>
> /* Enable the module's async AXI bridges. */
> - ASB_WRITE(reg, ASB_READ(reg) & ~ASB_REQ_STOP);
> - while (ASB_READ(reg) & ASB_ACK) {
> + ASB_WRITE(reg, ASB_READ(reg, is_v3d) & ~ASB_REQ_STOP, is_v3d);
> + while (ASB_READ(reg, is_v3d) & ASB_ACK) {
> cpu_relax();
> if (ktime_get_ns() - start >= 1000)
> return -ETIMEDOUT;
> @@ -168,7 +172,8 @@ static int bcm2835_asb_enable(struct bcm2835_power *power, u32 reg)
> return 0;
> }
>
> -static int bcm2835_asb_disable(struct bcm2835_power *power, u32 reg)
> +static int bcm2835_asb_disable(struct bcm2835_power *power, u32 reg,
> + bool is_v3d)
> {
> u64 start;
>
> @@ -178,8 +183,8 @@ static int bcm2835_asb_disable(struct bcm2835_power *power, u32 reg)
> start = ktime_get_ns();
>
> /* Enable the module's async AXI bridges. */
> - ASB_WRITE(reg, ASB_READ(reg) | ASB_REQ_STOP);
> - while (!(ASB_READ(reg) & ASB_ACK)) {
> + ASB_WRITE(reg, ASB_READ(reg, is_v3d) | ASB_REQ_STOP, is_v3d);
> + while (!(ASB_READ(reg, is_v3d) & ASB_ACK)) {
> cpu_relax();
> if (ktime_get_ns() - start >= 1000)
> return -ETIMEDOUT;
> @@ -274,7 +279,8 @@ static int bcm2835_asb_power_on(struct bcm2835_power_domain *pd,
> u32 pm_reg,
> u32 asb_m_reg,
> u32 asb_s_reg,
> - u32 reset_flags)
> + u32 reset_flags,
> + bool is_v3d)
> {
> struct bcm2835_power *power = pd->power;
> int ret;
> @@ -301,13 +307,13 @@ static int bcm2835_asb_power_on(struct bcm2835_power_domain *pd,
> goto err_enable_resets;
> }
>
> - ret = bcm2835_asb_enable(power, asb_m_reg);
> + ret = bcm2835_asb_enable(power, asb_m_reg, is_v3d);
> if (ret) {
> dev_err(power->dev, "Failed to enable ASB master for %s\n",
> pd->base.name);
> goto err_disable_clk;
> }
> - ret = bcm2835_asb_enable(power, asb_s_reg);
> + ret = bcm2835_asb_enable(power, asb_s_reg, is_v3d);
> if (ret) {
> dev_err(power->dev, "Failed to enable ASB slave for %s\n",
> pd->base.name);
> @@ -317,7 +323,7 @@ static int bcm2835_asb_power_on(struct bcm2835_power_domain *pd,
> return 0;
>
> err_disable_asb_master:
> - bcm2835_asb_disable(power, asb_m_reg);
> + bcm2835_asb_disable(power, asb_m_reg, is_v3d);
> err_disable_clk:
> clk_disable_unprepare(pd->clk);
> err_enable_resets:
> @@ -329,22 +335,23 @@ static int bcm2835_asb_power_off(struct bcm2835_power_domain *pd,
> u32 pm_reg,
> u32 asb_m_reg,
> u32 asb_s_reg,
> - u32 reset_flags)
> + u32 reset_flags,
> + bool is_v3d)
> {
> struct bcm2835_power *power = pd->power;
> int ret;
>
> - ret = bcm2835_asb_disable(power, asb_s_reg);
> + ret = bcm2835_asb_disable(power, asb_s_reg, is_v3d);
> if (ret) {
> dev_warn(power->dev, "Failed to disable ASB slave for %s\n",
> pd->base.name);
> return ret;
> }
> - ret = bcm2835_asb_disable(power, asb_m_reg);
> + ret = bcm2835_asb_disable(power, asb_m_reg, is_v3d);
> if (ret) {
> dev_warn(power->dev, "Failed to disable ASB master for %s\n",
> pd->base.name);
> - bcm2835_asb_enable(power, asb_s_reg);
> + bcm2835_asb_enable(power, asb_s_reg, is_v3d);
> return ret;
> }
>
> @@ -369,7 +376,7 @@ static int bcm2835_power_pd_power_on(struct generic_pm_domain *domain)
> case BCM2835_POWER_DOMAIN_GRAFX_V3D:
> return bcm2835_asb_power_on(pd, PM_GRAFX,
> ASB_V3D_M_CTRL, ASB_V3D_S_CTRL,
> - PM_V3DRSTN);
> + PM_V3DRSTN, true);
>
> case BCM2835_POWER_DOMAIN_IMAGE:
> return bcm2835_power_power_on(pd, PM_IMAGE);
> @@ -377,17 +384,17 @@ static int bcm2835_power_pd_power_on(struct generic_pm_domain *domain)
> case BCM2835_POWER_DOMAIN_IMAGE_PERI:
> return bcm2835_asb_power_on(pd, PM_IMAGE,
> 0, 0,
> - PM_PERIRSTN);
> + PM_PERIRSTN, false);
>
> case BCM2835_POWER_DOMAIN_IMAGE_ISP:
> return bcm2835_asb_power_on(pd, PM_IMAGE,
> ASB_ISP_M_CTRL, ASB_ISP_S_CTRL,
> - PM_ISPRSTN);
> + PM_ISPRSTN, false);
>
> case BCM2835_POWER_DOMAIN_IMAGE_H264:
> return bcm2835_asb_power_on(pd, PM_IMAGE,
> ASB_H264_M_CTRL, ASB_H264_S_CTRL,
> - PM_H264RSTN);
> + PM_H264RSTN, false);
>
> case BCM2835_POWER_DOMAIN_USB:
> PM_WRITE(PM_USB, PM_USB_CTRLEN);
> @@ -435,7 +442,7 @@ static int bcm2835_power_pd_power_off(struct generic_pm_domain *domain)
> case BCM2835_POWER_DOMAIN_GRAFX_V3D:
> return bcm2835_asb_power_off(pd, PM_GRAFX,
> ASB_V3D_M_CTRL, ASB_V3D_S_CTRL,
> - PM_V3DRSTN);
> + PM_V3DRSTN, true);
>
> case BCM2835_POWER_DOMAIN_IMAGE:
> return bcm2835_power_power_off(pd, PM_IMAGE);
> @@ -443,17 +450,17 @@ static int bcm2835_power_pd_power_off(struct generic_pm_domain *domain)
> case BCM2835_POWER_DOMAIN_IMAGE_PERI:
> return bcm2835_asb_power_off(pd, PM_IMAGE,
> 0, 0,
> - PM_PERIRSTN);
> + PM_PERIRSTN, false);
>
> case BCM2835_POWER_DOMAIN_IMAGE_ISP:
> return bcm2835_asb_power_off(pd, PM_IMAGE,
> ASB_ISP_M_CTRL, ASB_ISP_S_CTRL,
> - PM_ISPRSTN);
> + PM_ISPRSTN, false);
>
> case BCM2835_POWER_DOMAIN_IMAGE_H264:
> return bcm2835_asb_power_off(pd, PM_IMAGE,
> ASB_H264_M_CTRL, ASB_H264_S_CTRL,
> - PM_H264RSTN);
> + PM_H264RSTN, false);
>
> case BCM2835_POWER_DOMAIN_USB:
> PM_WRITE(PM_USB, 0);
> @@ -626,13 +633,22 @@ static int bcm2835_power_probe(struct platform_device *pdev)
> power->dev = dev;
> power->base = pm->base;
> power->rpivid_asb = pm->rpivid_asb;
> + power->argon_asb = pm->argon_asb;
>
> - id = ASB_READ(ASB_AXI_BRDG_ID);
> + id = ASB_READ(ASB_AXI_BRDG_ID, false);
> if (id != 0x62726467 /* "BRDG" */) {
> - dev_err(dev, "ASB register ID returned 0x%08x\n", id);
> + dev_err(dev, "RPiVid ASB register ID returned 0x%08x\n", id);
> return -ENODEV;
> }
>
> + if (pm->argon_asb) {
> + id = ASB_READ(ASB_AXI_BRDG_ID, true);
> + if (id != 0x62726467 /* "BRDG" */) {
> + dev_err(dev, "Argon ASB register ID returned 0x%08x\n", id);
> + return -ENODEV;
> + }
> + }
> +

Surely these are the same register. Is this the result of a bad merge?

Thanks,

Phil