Re: [PATCH v4 3/3] nvmem: rockchip-efuse: add rk3399-efuse support

Doug Anderson
2016-09-01T17:58:07Z

Hi,

On Mon, Aug 29, 2016 at 2:50 AM, Finley Xiao <finley.xiao-TNX95d0MmH7DzftRWevZcw@public.gmane.org> wrote:
> 1) the efuse timing of rk3399 is different from earlier SoCs.
> 2) rk3399-efuse is organized as 32bits by 32 one-time programmable
> electrical fuses, the efuse of earlier SoCs is organized as 32bits
> by 8 one-time programmable electrical fuses with random access interface.
>
> This patch adds a new read function for rk3399-efuse.
>
> Signed-off-by: Finley Xiao <finley.xiao-TNX95d0MmH7DzftRWevZcw@public.gmane.org>
> Reviewed-by: Heiko Stuebner <heiko-4mtYJXux2i+zQB+pC5nmwQ@public.gmane.org>
> ---
> drivers/nvmem/rockchip-efuse.c | 131 +++++++++++++++++++++++++++++++++++------
> 1 file changed, 112 insertions(+), 19 deletions(-)
>
> diff --git a/drivers/nvmem/rockchip-efuse.c b/drivers/nvmem/rockchip-efuse.c
> index 4d3f391..1825fd3 100644
> --- a/drivers/nvmem/rockchip-efuse.c
> +++ b/drivers/nvmem/rockchip-efuse.c
> @@ -22,17 +22,29 @@
> #include <linux/nvmem-provider.h>
> #include <linux/slab.h>
> #include <linux/of.h>
> +#include <linux/of_platform.h>
> #include <linux/platform_device.h>
>
> -#define EFUSE_A_SHIFT 6
> -#define EFUSE_A_MASK 0x3ff
> -#define EFUSE_PGENB BIT(3)
> -#define EFUSE_LOAD BIT(2)
> -#define EFUSE_STROBE BIT(1)
> -#define EFUSE_CSB BIT(0)
> -
> -#define REG_EFUSE_CTRL 0x0000
> -#define REG_EFUSE_DOUT 0x0004
> +#define RK3288_A_SHIFT 6
> +#define RK3288_A_MASK 0x3ff
> +#define RK3288_PGENB BIT(3)
> +#define RK3288_LOAD BIT(2)
> +#define RK3288_STROBE BIT(1)
> +#define RK3288_CSB BIT(0)
> +
> +#define RK3399_A_SHIFT 16
> +#define RK3399_A_MASK 0x3ff
> +#define RK3399_NBYTES 4
> +#define RK3399_STROBSFTSEL BIT(9)
> +#define RK3399_RSB BIT(7)
> +#define RK3399_PD BIT(5)
> +#define RK3399_PGENB BIT(3)
> +#define RK3399_LOAD BIT(2)
> +#define RK3399_STROBE BIT(1)
> +#define RK3399_CSB BIT(0)
> +
> +#define REG_EFUSE_CTRL 0x0000
> +#define REG_EFUSE_DOUT 0x0004

For me the alignment of the above is all off after your patch. Are
you sure you have your editor set to 8 spaces per tab?

>
> struct rockchip_efuse_chip {
> struct device *dev;
> @@ -40,8 +52,8 @@ struct rockchip_efuse_chip {
> struct clk *clk;
> };
>
> -static int rockchip_efuse_read(void *context, unsigned int offset,
> - void *val, size_t bytes)
> +static int rockchip_rk3288_efuse_read(void *context, unsigned int offset,
> + void *val, size_t bytes)
> {
> struct rockchip_efuse_chip *efuse = context;
> u8 *buf = val;
> @@ -53,27 +65,80 @@ static int rockchip_efuse_read(void *context, unsigned int offset,
> return ret;
> }
>
> - writel(EFUSE_LOAD | EFUSE_PGENB, efuse->base + REG_EFUSE_CTRL);
> + writel(RK3288_LOAD | RK3288_PGENB, efuse->base + REG_EFUSE_CTRL);
> udelay(1);
> while (bytes--) {
> writel(readl(efuse->base + REG_EFUSE_CTRL) &
> - (~(EFUSE_A_MASK << EFUSE_A_SHIFT)),
> + (~(RK3288_A_MASK << RK3288_A_SHIFT)),
> efuse->base + REG_EFUSE_CTRL);
> writel(readl(efuse->base + REG_EFUSE_CTRL) |
> - ((offset++ & EFUSE_A_MASK) << EFUSE_A_SHIFT),
> + ((offset++ & RK3288_A_MASK) << RK3288_A_SHIFT),
> efuse->base + REG_EFUSE_CTRL);
> udelay(1);
> writel(readl(efuse->base + REG_EFUSE_CTRL) |
> - EFUSE_STROBE, efuse->base + REG_EFUSE_CTRL);
> + RK3288_STROBE, efuse->base + REG_EFUSE_CTRL);
> udelay(1);
> *buf++ = readb(efuse->base + REG_EFUSE_DOUT);
> writel(readl(efuse->base + REG_EFUSE_CTRL) &
> - (~EFUSE_STROBE), efuse->base + REG_EFUSE_CTRL);
> + (~RK3288_STROBE), efuse->base + REG_EFUSE_CTRL);
> udelay(1);
> }
>
> /* Switch to standby mode */
> - writel(EFUSE_PGENB | EFUSE_CSB, efuse->base + REG_EFUSE_CTRL);
> + writel(RK3288_PGENB | RK3288_CSB, efuse->base + REG_EFUSE_CTRL);
> +
> + clk_disable_unprepare(efuse->clk);
> +
> + return 0;
> +}
> +
> +static int rockchip_rk3399_efuse_read(void *context, unsigned int offset,
> + void *val, size_t bytes)
> +{
> + struct rockchip_efuse_chip *efuse = context;
> + unsigned int addr_start, addr_end, addr_offset, addr_len;
> + u32 out_value;
> + u8 *buf;
> + int ret, i = 0;
> +
> + ret = clk_prepare_enable(efuse->clk);
> + if (ret < 0) {
> + dev_err(efuse->dev, "failed to prepare/enable efuse clk\n");
> + return ret;
> + }
> +
> + addr_start = rounddown(offset, RK3399_NBYTES) / RK3399_NBYTES;
> + addr_end = roundup(offset + bytes, RK3399_NBYTES) / RK3399_NBYTES;
> + addr_offset = offset % RK3399_NBYTES;
> + addr_len = addr_end - addr_start;
> +
> + buf = kzalloc(sizeof(*buf) * addr_len * RK3399_NBYTES, GFP_KERNEL);
> + if (!buf)
> + return -ENOMEM;

you forget to clk_disable_unprepare() here.

> +
> + writel(RK3399_LOAD | RK3399_PGENB | RK3399_STROBSFTSEL | RK3399_RSB,
> + efuse->base + REG_EFUSE_CTRL);
> + udelay(1);
> + while (addr_len--) {
> + writel(readl(efuse->base + REG_EFUSE_CTRL) | RK3399_STROBE |
> + ((addr_start++ & RK3399_A_MASK) << RK3399_A_SHIFT),
> + efuse->base + REG_EFUSE_CTRL);
> + udelay(1);
> + out_value = readl(efuse->base + REG_EFUSE_DOUT);
> + writel(readl(efuse->base + REG_EFUSE_CTRL) & (~RK3399_STROBE),
> + efuse->base + REG_EFUSE_CTRL);
> + udelay(1);
> +
> + memcpy(&buf[i], &out_value, RK3399_NBYTES);
> + i += RK3399_NBYTES;
> + }
> +
> + /* Switch to standby mode */
> + writel(RK3399_PD | RK3399_CSB, efuse->base + REG_EFUSE_CTRL);
> +
> + memcpy(val, buf + addr_offset, bytes);
> +
> + kfree(buf);
>
> clk_disable_unprepare(efuse->clk);
>
> @@ -89,7 +154,27 @@ static struct nvmem_config econfig = {
> };
>
> static const struct of_device_id rockchip_efuse_match[] = {
> - { .compatible = "rockchip,rockchip-efuse", },
> + /* deprecated but kept around for dts binding compatibility */
> + {
> + .compatible = "rockchip,rockchip-efuse",
> + .data = (void *)&rockchip_rk3288_efuse_read,
> + },
> + {
> + .compatible = "rockchip,rk3066a-efuse",
> + .data = (void *)&rockchip_rk3288_efuse_read,
> + },
> + {
> + .compatible = "rockchip,rk3188-efuse",
> + .data = (void *)&rockchip_rk3288_efuse_read,
> + },
> + {
> + .compatible = "rockchip,rk3288-efuse",
> + .data = (void *)&rockchip_rk3288_efuse_read,
> + },
> + {
> + .compatible = "rockchip,rk3399-efuse",
> + .data = (void *)&rockchip_rk3399_efuse_read,
> + },
> { /* sentinel */},
> };
> MODULE_DEVICE_TABLE(of, rockchip_efuse_match);
> @@ -99,6 +184,14 @@ static int rockchip_efuse_probe(struct platform_device *pdev)
> struct resource *res;
> struct nvmem_device *nvmem;
> struct rockchip_efuse_chip *efuse;
> + const struct of_device_id *match;
> + struct device *dev = &pdev->dev;
> +
> + match = of_match_device(dev->driver->of_match_table, dev);
> + if (!match || !match->data) {
> + dev_err(dev, "failed to get match data\n");
> + return -EINVAL;
> + }
>
> efuse = devm_kzalloc(&pdev->dev, sizeof(struct rockchip_efuse_chip),
> GFP_KERNEL);
> @@ -116,7 +209,7 @@ static int rockchip_efuse_probe(struct platform_device *pdev)
>
> efuse->dev = &pdev->dev;
> econfig.size = resource_size(res);
> - econfig.reg_read = rockchip_efuse_read;
> + econfig.reg_read = match->data;
> econfig.priv = efuse;
> econfig.dev = efuse->dev;
> nvmem = nvmem_register(&econfig);
> --
> 1.9.1
>
>