Re: [PATCH] drm/bridge/synopsys: dsi: Add 1.31 version support
From: Philippe CORNU
Date: Mon Feb 05 2018 - 10:00:20 EST
Hi Andrzej,
And many thanks for your good comments
On 02/05/2018 02:03 PM, Andrzej Hajda wrote:
> On 22.01.2018 16:08, Philippe Cornu wrote:
>> From: Philippe CORNU <philippe.cornu@xxxxxx>
>>
>> Add support for the Synopsys DesignWare MIPI DSI version 1.31
>> Two registers need to be updated/added for supporting 1.31:
>> * PHY_TMR_CFG 0x9c (updated)
>> 1.30 [31:24] phy_hs2lp_time
>> [23:16] phy_lp2hs_time
>> [14: 0] max_rd_time
>>
>> 1.31 [25:16] phy_hs2lp_time
>> [ 9: 0] phy_lp2hs_time
>>
>> * PHY_TMR_RD_CFG 0xf4 (new)
>> 1.31 [14: 0] max_rd_time
>>
>> Signed-off-by: Philippe Cornu <philippe.cornu@xxxxxx>
>> ---
>> drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c | 52 +++++++++++++++++++++++----
>> 1 file changed, 46 insertions(+), 6 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
>> index 735f38429c06..20a2ca14a7ad 100644
>> --- a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
>> +++ b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
>> @@ -25,7 +25,13 @@
>> #include <drm/bridge/dw_mipi_dsi.h>
>> #include <video/mipi_display.h>
>>
>> +#define HWVER_130 0x31333000 /* IP version 1.30 */
>> +#define HWVER_131 0x31333100 /* IP version 1.31 */
>> +#define HWVER_OLDEST HWVER_130
>> +#define HWVER_NEWEST HWVER_131
>> +
>> #define DSI_VERSION 0x00
>> +#define VERSION GENMASK(31, 8)
>>
>> #define DSI_PWR_UP 0x04
>> #define RESET 0
>> @@ -161,11 +167,12 @@
>> #define PHY_CLKHS2LP_TIME(lbcc) (((lbcc) & 0x3ff) << 16)
>> #define PHY_CLKLP2HS_TIME(lbcc) ((lbcc) & 0x3ff)
>>
>> -/* TODO Next register is slightly different between 1.30 & 1.31 IP version */
>> #define DSI_PHY_TMR_CFG 0x9c
>> -#define PHY_HS2LP_TIME(lbcc) (((lbcc) & 0xff) << 24)
>> -#define PHY_LP2HS_TIME(lbcc) (((lbcc) & 0xff) << 16)
>> -#define MAX_RD_TIME(lbcc) ((lbcc) & 0x7fff)
>> +#define PHY_HS2LP_TIME_V130(lbcc) (((lbcc) & 0xff) << 24)
>> +#define PHY_LP2HS_TIME_V130(lbcc) (((lbcc) & 0xff) << 16)
>> +#define MAX_RD_TIME_V130(lbcc) ((lbcc) & 0x7fff)
>> +#define PHY_HS2LP_TIME_V131(lbcc) (((lbcc) & 0x3ff) << 16)
>> +#define PHY_LP2HS_TIME_V131(lbcc) ((lbcc) & 0x3ff)
>>
>> #define DSI_PHY_RSTZ 0xa0
>> #define PHY_DISFORCEPLL 0
>> @@ -204,7 +211,9 @@
>> #define DSI_INT_ST1 0xc0
>> #define DSI_INT_MSK0 0xc4
>> #define DSI_INT_MSK1 0xc8
>> +
>> #define DSI_PHY_TMR_RD_CFG 0xf4
>> +#define MAX_RD_TIME_V131(lbcc) ((lbcc) & 0x7fff)
>>
>> #define PHY_STATUS_TIMEOUT_US 10000
>> #define CMD_PKT_STATUS_TIMEOUT_US 20000
>> @@ -215,6 +224,7 @@ struct dw_mipi_dsi {
>> struct drm_bridge *panel_bridge;
>> struct device *dev;
>> void __iomem *base;
>> + u32 hw_version;
>>
>> struct clk *pclk;
>> struct clk *px_clk;
>> @@ -616,8 +626,14 @@ static void dw_mipi_dsi_dphy_timing_config(struct dw_mipi_dsi *dsi)
>> * note: DSI_PHY_TMR_CFG.MAX_RD_TIME should be in line with
>> * DSI_CMD_MODE_CFG.MAX_RD_PKT_SIZE_LP (see CMD_MODE_ALL_LP)
>> */
>> - dsi_write(dsi, DSI_PHY_TMR_CFG, PHY_HS2LP_TIME(0x40)
>> - | PHY_LP2HS_TIME(0x40) | MAX_RD_TIME(10000));
>> + if (dsi->hw_version == HWVER_131) {
>> + dsi_write(dsi, DSI_PHY_TMR_CFG, PHY_HS2LP_TIME_V131(0x40) |
>> + PHY_LP2HS_TIME_V131(0x40));
>> + dsi_write(dsi, DSI_PHY_TMR_RD_CFG, MAX_RD_TIME_V131(10000));
>> + } else {
>> + dsi_write(dsi, DSI_PHY_TMR_CFG, PHY_HS2LP_TIME_V130(0x40) |
>> + PHY_LP2HS_TIME_V130(0x40) | MAX_RD_TIME_V130(10000));
>> + }
>>
>> dsi_write(dsi, DSI_PHY_TMR_LPCLK_CFG, PHY_CLKHS2LP_TIME(0x40)
>> | PHY_CLKLP2HS_TIME(0x40));
>> @@ -791,6 +807,28 @@ static const struct drm_bridge_funcs dw_mipi_dsi_bridge_funcs = {
>> .attach = dw_mipi_dsi_bridge_attach,
>> };
>>
>> +static void dsi_get_version(struct dw_mipi_dsi *dsi)
>> +{
>> + u32 hw_version;
>> +
>> + clk_prepare_enable(dsi->pclk);
>> + hw_version = dsi_read(dsi, DSI_VERSION) & VERSION;
>> + clk_disable_unprepare(dsi->pclk);
>> +
>> + if (hw_version > HWVER_NEWEST) {
>> + DRM_DEBUG("hw version: use 0x%08x for this recent 0x%08x\n",
>> + HWVER_NEWEST, hw_version);
>> + hw_version = HWVER_NEWEST;
>> +
>> + } else if (hw_version < HWVER_OLDEST) {
>> + DRM_DEBUG("hw version: use 0x%08x for this old 0x%08x\n",
>> + HWVER_OLDEST, hw_version);
>> + hw_version = HWVER_OLDEST;
>> + }
>> +
>> + dsi->hw_version = hw_version;
>> +}
>> +
>> static struct dw_mipi_dsi *
>> __dw_mipi_dsi_probe(struct platform_device *pdev,
>> const struct dw_mipi_dsi_plat_data *plat_data)
>> @@ -870,6 +908,8 @@ __dw_mipi_dsi_probe(struct platform_device *pdev,
>> clk_disable_unprepare(dsi->pclk);
>> }
>>
>> + dsi_get_version(dsi);
>> +
>> pm_runtime_enable(dev);
>
> Two questions:
> 1. You have generally two variants:
> - older than 131,
> - not older than 131.
> Wouldn't be better to just assume that since 131 registers slightly differ?
> So you just stores:
> ÂÂÂ dsi->hw_version = dsi_read(dsi, DSI_VERSION) & VERSION;
> And if neccessary performs comparison:
> ÂÂÂ if (dsi->hw_version >= HWVER_131)
> ÂÂÂ ÂÂÂ ...
> ÂÂÂ else
> ÂÂÂ ÂÂÂ ...
>
> This way you can remove these HWVER_(NEWEST|OLDEST).
>
Archit & you are right, my code is too complex for at the end only 2
different reg writes for the 1.31 version :)
I will follow all your good tips to simplify the code.
> 2. You are using pm_runtime, but not in dsi_get_version. I guess it is
> SoC dependant but I suppose performing registry read should be safer
> after runtime_get.
>
> Regards
> Andrzej
>
dsi_get_version() is called only once and just before pm_runtime_enable().
Anyway, I think this function is not required anymore as there is only
one place where we need to take care of the 1.31 version.
Many thanks,
Philippe :-)
>>
>> dsi->dsi_host.ops = &dw_mipi_dsi_host_ops;
>
>