2020-10-25 09:38:41

by Vidya Sagar

[permalink] [raw]
Subject: [PATCH 0/2] Add support to configure DWC for ECRC

This series has two patches.

Patch-1: Adds a public API to query if the system has ECRC policty turned on.

Patch-2: DesignWare core PCIe IP has a TLP Digest (TD) override bit in one of
its control registers of ATU. This bit needs to be programmed for proper ECRC
functionality. This is currently identified as an issue with DesignWare
IP version 4.90a. DWC code queries the PCIe sub-system through the API added
in Patch-1 to find out if ECRC is turned on or not and configures ATU
accordingly.

Vidya Sagar (2):
PCI/AER: Add pcie_is_ecrc_enabled() API
PCI: dwc: Add support to configure for ECRC

drivers/pci/controller/dwc/pcie-designware.c | 8 ++++++--
drivers/pci/controller/dwc/pcie-designware.h | 2 ++
drivers/pci/pci.h | 2 ++
drivers/pci/pcie/aer.c | 11 +++++++++++
4 files changed, 21 insertions(+), 2 deletions(-)

--
2.17.1


2020-10-25 09:41:01

by Vidya Sagar

[permalink] [raw]
Subject: [PATCH 1/2] PCI/AER: Add pcie_is_ecrc_enabled() API

Adds pcie_is_ecrc_enabled() API to let other sub-systems (like DesignWare)
to query if ECRC policy is enabled and perform any configuration
required in those respective sub-systems.

Signed-off-by: Vidya Sagar <[email protected]>
---
drivers/pci/pci.h | 2 ++
drivers/pci/pcie/aer.c | 11 +++++++++++
2 files changed, 13 insertions(+)

diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index fa12f7cbc1a0..325fdbf91dde 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -575,9 +575,11 @@ static inline void pcie_aspm_powersave_config_link(struct pci_dev *pdev) { }
#ifdef CONFIG_PCIE_ECRC
void pcie_set_ecrc_checking(struct pci_dev *dev);
void pcie_ecrc_get_policy(char *str);
+bool pcie_is_ecrc_enabled(void);
#else
static inline void pcie_set_ecrc_checking(struct pci_dev *dev) { }
static inline void pcie_ecrc_get_policy(char *str) { }
+static inline bool pcie_is_ecrc_enabled(void) { return false; }
#endif

#ifdef CONFIG_PCIE_PTM
diff --git a/drivers/pci/pcie/aer.c b/drivers/pci/pcie/aer.c
index 65dff5f3457a..24363c895aba 100644
--- a/drivers/pci/pcie/aer.c
+++ b/drivers/pci/pcie/aer.c
@@ -207,6 +207,17 @@ void pcie_ecrc_get_policy(char *str)

ecrc_policy = i;
}
+
+/**
+ * pcie_is_ecrc_enabled - returns if ECRC is enabled in the system or not
+ *
+ * Returns 1 if ECRC policy is enabled and 0 otherwise
+ */
+bool pcie_is_ecrc_enabled(void)
+{
+ return ecrc_policy == ECRC_POLICY_ON;
+}
+EXPORT_SYMBOL(pcie_is_ecrc_enabled);
#endif /* CONFIG_PCIE_ECRC */

#define PCI_EXP_AER_FLAGS (PCI_EXP_DEVCTL_CERE | PCI_EXP_DEVCTL_NFERE | \
--
2.17.1

2020-10-25 12:17:11

by Vidya Sagar

[permalink] [raw]
Subject: [PATCH 2/2] PCI: dwc: Add support to configure for ECRC

DesignWare core has a TLP digest (TD) override bit in one of the control
registers of ATU. This bit also needs to be programmed for proper ECRC
functionality. This is currently identified as an issue with DesignWare
IP version 4.90a. This patch does the required programming in ATU upon
querying the system policy for ECRC.

Signed-off-by: Vidya Sagar <[email protected]>
---
drivers/pci/controller/dwc/pcie-designware.c | 8 ++++++--
drivers/pci/controller/dwc/pcie-designware.h | 2 ++
2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c
index b5e438b70cd5..810dcbdbe869 100644
--- a/drivers/pci/controller/dwc/pcie-designware.c
+++ b/drivers/pci/controller/dwc/pcie-designware.c
@@ -245,7 +245,7 @@ static void dw_pcie_prog_outbound_atu_unroll(struct dw_pcie *pci, u8 func_no,
lower_32_bits(pci_addr));
dw_pcie_writel_ob_unroll(pci, index, PCIE_ATU_UNR_UPPER_TARGET,
upper_32_bits(pci_addr));
- val = type | PCIE_ATU_FUNC_NUM(func_no);
+ val = type | PCIE_ATU_FUNC_NUM(func_no) | pci->td << PCIE_ATU_TD_SHIFT;
val = upper_32_bits(size - 1) ?
val | PCIE_ATU_INCREASE_REGION_SIZE : val;
dw_pcie_writel_ob_unroll(pci, index, PCIE_ATU_UNR_REGION_CTRL1, val);
@@ -295,7 +295,8 @@ static void __dw_pcie_prog_outbound_atu(struct dw_pcie *pci, u8 func_no,
dw_pcie_writel_dbi(pci, PCIE_ATU_UPPER_TARGET,
upper_32_bits(pci_addr));
dw_pcie_writel_dbi(pci, PCIE_ATU_CR1, type |
- PCIE_ATU_FUNC_NUM(func_no));
+ PCIE_ATU_FUNC_NUM(func_no) |
+ pci->td << PCIE_ATU_TD_SHIFT);
dw_pcie_writel_dbi(pci, PCIE_ATU_CR2, PCIE_ATU_ENABLE);

/*
@@ -565,6 +566,9 @@ void dw_pcie_setup(struct dw_pcie *pci)
dev_dbg(pci->dev, "iATU unroll: %s\n", pci->iatu_unroll_enabled ?
"enabled" : "disabled");

+ if (pci->version == 0x490A)
+ pci->td = pcie_is_ecrc_enabled();
+
if (pci->link_gen > 0)
dw_pcie_link_set_max_speed(pci, pci->link_gen);

diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h
index 21dd06831b50..d34723e42e79 100644
--- a/drivers/pci/controller/dwc/pcie-designware.h
+++ b/drivers/pci/controller/dwc/pcie-designware.h
@@ -90,6 +90,7 @@
#define PCIE_ATU_TYPE_IO 0x2
#define PCIE_ATU_TYPE_CFG0 0x4
#define PCIE_ATU_TYPE_CFG1 0x5
+#define PCIE_ATU_TD_SHIFT 8
#define PCIE_ATU_FUNC_NUM(pf) ((pf) << 20)
#define PCIE_ATU_CR2 0x908
#define PCIE_ATU_ENABLE BIT(31)
@@ -276,6 +277,7 @@ struct dw_pcie {
int num_lanes;
int link_gen;
u8 n_fts[2];
+ bool td; /* TLP Digest (for ECRC purpose) */
};

#define to_dw_pcie_from_pp(port) container_of((port), struct dw_pcie, pp)
--
2.17.1

2020-10-25 22:20:53

by Jingoo Han

[permalink] [raw]
Subject: Re: [PATCH 2/2] PCI: dwc: Add support to configure for ECRC

On 10/25/20, 3:31 AM, Vidya Sagar wrote:
>
> DesignWare core has a TLP digest (TD) override bit in one of the control
> registers of ATU. This bit also needs to be programmed for proper ECRC
> functionality. This is currently identified as an issue with DesignWare
> IP version 4.90a. This patch does the required programming in ATU upon
> querying the system policy for ECRC.
>
> Signed-off-by: Vidya Sagar <[email protected]>
> ---
> drivers/pci/controller/dwc/pcie-designware.c | 8 ++++++--
> drivers/pci/controller/dwc/pcie-designware.h | 2 ++
> 2 files changed, 8 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c
> index b5e438b70cd5..810dcbdbe869 100644
> --- a/drivers/pci/controller/dwc/pcie-designware.c
> +++ b/drivers/pci/controller/dwc/pcie-designware.c
> @@ -245,7 +245,7 @@ static void dw_pcie_prog_outbound_atu_unroll(struct dw_pcie *pci, u8 func_no,
> lower_32_bits(pci_addr));
> dw_pcie_writel_ob_unroll(pci, index, PCIE_ATU_UNR_UPPER_TARGET,
> upper_32_bits(pci_addr));
> - val = type | PCIE_ATU_FUNC_NUM(func_no);
> + val = type | PCIE_ATU_FUNC_NUM(func_no) | pci->td << PCIE_ATU_TD_SHIFT;
> val = upper_32_bits(size - 1) ?
> val | PCIE_ATU_INCREASE_REGION_SIZE : val;
> dw_pcie_writel_ob_unroll(pci, index, PCIE_ATU_UNR_REGION_CTRL1, val);
> @@ -295,7 +295,8 @@ static void __dw_pcie_prog_outbound_atu(struct dw_pcie *pci, u8 func_no,
> dw_pcie_writel_dbi(pci, PCIE_ATU_UPPER_TARGET,
> upper_32_bits(pci_addr));
> dw_pcie_writel_dbi(pci, PCIE_ATU_CR1, type |
> - PCIE_ATU_FUNC_NUM(func_no));
> + PCIE_ATU_FUNC_NUM(func_no) |
> + pci->td << PCIE_ATU_TD_SHIFT);
> dw_pcie_writel_dbi(pci, PCIE_ATU_CR2, PCIE_ATU_ENABLE);
>
> /*
> @@ -565,6 +566,9 @@ void dw_pcie_setup(struct dw_pcie *pci)
> dev_dbg(pci->dev, "iATU unroll: %s\n", pci->iatu_unroll_enabled ?
> "enabled" : "disabled");
>
> + if (pci->version == 0x490A)
> + pci->td = pcie_is_ecrc_enabled();
> +
> if (pci->link_gen > 0)
> dw_pcie_link_set_max_speed(pci, pci->link_gen);
>
> diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h
> index 21dd06831b50..d34723e42e79 100644
> --- a/drivers/pci/controller/dwc/pcie-designware.h
> +++ b/drivers/pci/controller/dwc/pcie-designware.h
> @@ -90,6 +90,7 @@
> #define PCIE_ATU_TYPE_IO 0x2
> #define PCIE_ATU_TYPE_CFG0 0x4
> #define PCIE_ATU_TYPE_CFG1 0x5
> +#define PCIE_ATU_TD_SHIFT 8
> #define PCIE_ATU_FUNC_NUM(pf) ((pf) << 20)
> #define PCIE_ATU_CR2 0x908
> #define PCIE_ATU_ENABLE BIT(31)
> @@ -276,6 +277,7 @@ struct dw_pcie {
> int num_lanes;
> int link_gen;
> u8 n_fts[2];
> + bool td; /* TLP Digest (for ECRC purpose) */

If possible, don't add a new variable to 'dw_pcie' structure.
Please find a way to set TD bit without adding a new variable to 'dw_pcie' structure'.

Best regards,
Jingoo Han

> };
>
> #define to_dw_pcie_from_pp(port) container_of((port), struct dw_pcie, pp)
> --
> 2.17.1

2020-10-26 08:16:18

by Vidya Sagar

[permalink] [raw]
Subject: Re: [PATCH 2/2] PCI: dwc: Add support to configure for ECRC



On 10/26/2020 2:19 AM, Jingoo Han wrote:
> External email: Use caution opening links or attachments
>
>
> On 10/25/20, 3:31 AM, Vidya Sagar wrote:
>>
>> DesignWare core has a TLP digest (TD) override bit in one of the control
>> registers of ATU. This bit also needs to be programmed for proper ECRC
>> functionality. This is currently identified as an issue with DesignWare
>> IP version 4.90a. This patch does the required programming in ATU upon
>> querying the system policy for ECRC.
>>
>> Signed-off-by: Vidya Sagar <[email protected]>
>> ---
>> drivers/pci/controller/dwc/pcie-designware.c | 8 ++++++--
>> drivers/pci/controller/dwc/pcie-designware.h | 2 ++
>> 2 files changed, 8 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c
>> index b5e438b70cd5..810dcbdbe869 100644
>> --- a/drivers/pci/controller/dwc/pcie-designware.c
>> +++ b/drivers/pci/controller/dwc/pcie-designware.c
>> @@ -245,7 +245,7 @@ static void dw_pcie_prog_outbound_atu_unroll(struct dw_pcie *pci, u8 func_no,
>> lower_32_bits(pci_addr));
>> dw_pcie_writel_ob_unroll(pci, index, PCIE_ATU_UNR_UPPER_TARGET,
>> upper_32_bits(pci_addr));
>> - val = type | PCIE_ATU_FUNC_NUM(func_no);
>> + val = type | PCIE_ATU_FUNC_NUM(func_no) | pci->td << PCIE_ATU_TD_SHIFT;
>> val = upper_32_bits(size - 1) ?
>> val | PCIE_ATU_INCREASE_REGION_SIZE : val;
>> dw_pcie_writel_ob_unroll(pci, index, PCIE_ATU_UNR_REGION_CTRL1, val);
>> @@ -295,7 +295,8 @@ static void __dw_pcie_prog_outbound_atu(struct dw_pcie *pci, u8 func_no,
>> dw_pcie_writel_dbi(pci, PCIE_ATU_UPPER_TARGET,
>> upper_32_bits(pci_addr));
>> dw_pcie_writel_dbi(pci, PCIE_ATU_CR1, type |
>> - PCIE_ATU_FUNC_NUM(func_no));
>> + PCIE_ATU_FUNC_NUM(func_no) |
>> + pci->td << PCIE_ATU_TD_SHIFT);
>> dw_pcie_writel_dbi(pci, PCIE_ATU_CR2, PCIE_ATU_ENABLE);
>>
>> /*
>> @@ -565,6 +566,9 @@ void dw_pcie_setup(struct dw_pcie *pci)
>> dev_dbg(pci->dev, "iATU unroll: %s\n", pci->iatu_unroll_enabled ?
>> "enabled" : "disabled");
>>
>> + if (pci->version == 0x490A)
>> + pci->td = pcie_is_ecrc_enabled();
>> +
>> if (pci->link_gen > 0)
>> dw_pcie_link_set_max_speed(pci, pci->link_gen);
>>
>> diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h
>> index 21dd06831b50..d34723e42e79 100644
>> --- a/drivers/pci/controller/dwc/pcie-designware.h
>> +++ b/drivers/pci/controller/dwc/pcie-designware.h
>> @@ -90,6 +90,7 @@
>> #define PCIE_ATU_TYPE_IO 0x2
>> #define PCIE_ATU_TYPE_CFG0 0x4
>> #define PCIE_ATU_TYPE_CFG1 0x5
>> +#define PCIE_ATU_TD_SHIFT 8
>> #define PCIE_ATU_FUNC_NUM(pf) ((pf) << 20)
>> #define PCIE_ATU_CR2 0x908
>> #define PCIE_ATU_ENABLE BIT(31)
>> @@ -276,6 +277,7 @@ struct dw_pcie {
>> int num_lanes;
>> int link_gen;
>> u8 n_fts[2];
>> + bool td; /* TLP Digest (for ECRC purpose) */
>
> If possible, don't add a new variable to 'dw_pcie' structure.
> Please find a way to set TD bit without adding a new variable to 'dw_pcie' structure'.

I can use pcie_is_ecrc_enabled() directly in place of pci->td. That
should be fine right? BTW, curious to know if there is any specific
reason behind asking not to add any new variables to 'dw_pcie' structure?

>
> Best regards,
> Jingoo Han
>
>> };
>>
>> #define to_dw_pcie_from_pp(port) container_of((port), struct dw_pcie, pp)
>> --
>> 2.17.1
>

2020-10-26 17:31:52

by Jingoo Han

[permalink] [raw]
Subject: Re: [PATCH 2/2] PCI: dwc: Add support to configure for ECRC



On 10/26/20, 2:59 AM, Vidya Sagar wrote:
>
> On 10/26/2020 2:19 AM, Jingoo Han wrote:
> > External email: Use caution opening links or attachments
> >
> >
> > On 10/25/20, 3:31 AM, Vidya Sagar wrote:
> >>
> >> DesignWare core has a TLP digest (TD) override bit in one of the control
> >> registers of ATU. This bit also needs to be programmed for proper ECRC
> >> functionality. This is currently identified as an issue with DesignWare
> >> IP version 4.90a. This patch does the required programming in ATU upon
> >> querying the system policy for ECRC.
> >>
> >> Signed-off-by: Vidya Sagar <[email protected]>
> >> ---
> >> drivers/pci/controller/dwc/pcie-designware.c | 8 ++++++--
> >> drivers/pci/controller/dwc/pcie-designware.h | 2 ++
> >> 2 files changed, 8 insertions(+), 2 deletions(-)
> >>
> >> diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c
> >> index b5e438b70cd5..810dcbdbe869 100644
> >> --- a/drivers/pci/controller/dwc/pcie-designware.c
> >> +++ b/drivers/pci/controller/dwc/pcie-designware.c
> >> @@ -245,7 +245,7 @@ static void dw_pcie_prog_outbound_atu_unroll(struct dw_pcie *pci, u8 func_no,
> >> lower_32_bits(pci_addr));
> >> dw_pcie_writel_ob_unroll(pci, index, PCIE_ATU_UNR_UPPER_TARGET,
> >> upper_32_bits(pci_addr));
> >> - val = type | PCIE_ATU_FUNC_NUM(func_no);
> >> + val = type | PCIE_ATU_FUNC_NUM(func_no) | pci->td << PCIE_ATU_TD_SHIFT;
> >> val = upper_32_bits(size - 1) ?
> >> val | PCIE_ATU_INCREASE_REGION_SIZE : val;
> >> dw_pcie_writel_ob_unroll(pci, index, PCIE_ATU_UNR_REGION_CTRL1, val);
> >> @@ -295,7 +295,8 @@ static void __dw_pcie_prog_outbound_atu(struct dw_pcie *pci, u8 func_no,
> >> dw_pcie_writel_dbi(pci, PCIE_ATU_UPPER_TARGET,
> >> upper_32_bits(pci_addr));
> >> dw_pcie_writel_dbi(pci, PCIE_ATU_CR1, type |
> >> - PCIE_ATU_FUNC_NUM(func_no));
> >> + PCIE_ATU_FUNC_NUM(func_no) |
> >> + pci->td << PCIE_ATU_TD_SHIFT);
> >> dw_pcie_writel_dbi(pci, PCIE_ATU_CR2, PCIE_ATU_ENABLE);
> >>
> >> /*
> >> @@ -565,6 +566,9 @@ void dw_pcie_setup(struct dw_pcie *pci)
> >> dev_dbg(pci->dev, "iATU unroll: %s\n", pci->iatu_unroll_enabled ?
> >> "enabled" : "disabled");
> >>
> >> + if (pci->version == 0x490A)
> >> + pci->td = pcie_is_ecrc_enabled();
> >> +
> >> if (pci->link_gen > 0)
> >> dw_pcie_link_set_max_speed(pci, pci->link_gen);
> >>
> >> diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h
> >> index 21dd06831b50..d34723e42e79 100644
> >> --- a/drivers/pci/controller/dwc/pcie-designware.h
> >> +++ b/drivers/pci/controller/dwc/pcie-designware.h
> >> @@ -90,6 +90,7 @@
> >> #define PCIE_ATU_TYPE_IO 0x2
> >> #define PCIE_ATU_TYPE_CFG0 0x4
> >> #define PCIE_ATU_TYPE_CFG1 0x5
> >> +#define PCIE_ATU_TD_SHIFT 8
> >> #define PCIE_ATU_FUNC_NUM(pf) ((pf) << 20)
> >> #define PCIE_ATU_CR2 0x908
> >> #define PCIE_ATU_ENABLE BIT(31)
> >> @@ -276,6 +277,7 @@ struct dw_pcie {
> >> int num_lanes;
> >> int link_gen;
> >> u8 n_fts[2];
> >> + bool td; /* TLP Digest (for ECRC purpose) */
> >
> > If possible, don't add a new variable to 'dw_pcie' structure.
> > Please find a way to set TD bit without adding a new variable to 'dw_pcie' structure'.
>
> I can use pcie_is_ecrc_enabled() directly in place of pci->td. That
> should be fine right? BTW, curious to know if there is any specific
> reason behind asking not to add any new variables to 'dw_pcie' structure?
>

Vice versa, what is the reason to add a new variable 'td' to 'dw_pcie' structure?
It is not good to add a new variable to the global structure without any specific reason.


> >
> Best regards,
> Jingoo Han
>
>> };
>>
>> #define to_dw_pcie_from_pp(port) container_of((port), struct dw_pcie, pp)
>> --
>> 2.17.1
>